HomeMy WebLinkAbout1999-11-15 City Council (6)TO:
City of Palo Alto
City Manager’s Report 7
HONORABLE CITY COUNCIL ..
FROM:CITY MANAGER DEPARTMENT: POLICE
DATE:NOVEMBER 15, 1999 CMR:412:99
SUBJECT:RECOMMENDATIONS REGARDING THE USE OF LEAF
BLOWERS IN PALO ALTO
RECOMMENDATION
Staff recommends that Council direct staff to revise Chapter 9.10 of the Palo Alto Municipal Code
regulating leaf blowers in the following manner:
1)
2)
3)
4)
5)
6)
7)
8)
9)
.10)
11)
12)
Allow only commercial gardeners!landscapers who are trained and certified by a City-approved
process to operate fuel-powered leaf blowers within the City limits;
Allow only leaf blowers (fuel and electric) with manufacturers’ affixed labels and
corresponding model numbers indicating an American National Standards Institute (ANSI)
noise level rating of 65 dBA or less at 50 feet to be used within the City limits;
Encourage the use of leaf blowers (fuel and electric) rate at 62 dBA or less by the year 2003;
Allow the use of fuel-powered leaf blowers between the hours of 8:00 a.m. and 5:00 p.m.
Monday through Friday;
Allow commercial use of fu.el-powered leaf blowers in industrial areas on Saturdays between
10:00 a.m. and 4:00 p.m.;
Allow residents (and commercial gardeners) to use electric leaf blowers between the hours of
8:00 a.m. and 6:00 p.m. Monday through Friday, and between 10:00 a.m. and 4:00 p.m. on
Saturdays;
Prohibit the use of all fuel-powered leaf blowers on Sundays and holidays
Conduct enforcement on a proactive basis, utilizing citations and an increasing scale as well as
notification of violations to commercial gardeners’ clients at the location of the violation;
Allow City crews to operate leaf blowers between 4:00 a.m. and 8:00 a.m. in the Downtown
area, California Avenue area, Midtown area, the Municipal Golf Course, and in City parking
facilities, with special consideration given to those areas immediately adjacent to hotels and
residential properties;
Exempt City crews from the regulations for clean up after special events and in emergencies;
Prohibit City crews and discourage commercial gardeners from using fuel-powered leaf blowers
on Spare the Air Days;
Require the use of factory installed mufflers and full extension tubes while leaf blowers are in
operation;
CMR:412:99 Page 1 of 4
14)
Prohibit the blowing of debris onto adjacent properties...
Include all contractors directly hired by the City under the definition of City crews;
BACKGROUND
At the Policy and Services Committee meeting of September 14, 1999, staff recommended that the
Council direct staff to revise Palo Alto Municipal Code Chapter 9.10 governing leaf bl’ower use. Staff
presented a list of regulations that would be included in the revised ordinance. Staff had inadvertently
excluded several regulations from that list. Additionally, Committee members requested the following:
that consideration be given by City crews of their use of leaf blowers between 4:00 a.m. and 8:00 a.m.
not only adjacent to hotels, but also to residential properties; that staff further study leaf blower use in
commercial areas adjacent to non-residential, private properties; and to include in the definition of City
crews any contractors directly employed by the City.
DISCUSSION
This report provides a list of regulations that have been revised according to the Committee direction
and updated information regarding the California Resources Board report on leaf blowers.
Regulation #2 was revised to incorporate the suggestion by Council member Rosenbaum that accepted
leaf blower model numbers be used in conjunction with manufacturers’ labels for enforcement purposes
to help ensure that labels were not attached to noncompliant blowers.
Staff concurs with the Council direction to include in the definition of City crews all contractors
employed directly by the City, and regulation #12 has been added to the list. This would clarify that
under the City’s contractors would also be prohibited from using fuel-powered leaf blowers on Spare
the Air Days.
Under the ctirrent.ordinance, City crews have been allowed to use leaf blowers between 10:00 p.m. and
7:00 a.m. Due to the number of noise complaints received, the schedule was changed two to three years
ago to 4:00 a.m. to 12:00 p.m. In February, staffproposed codifying the change in the revised ordinance
that would allow City crews to operate blowers between 4:00 a.m. and 8:00 a.m., hours that would
represent an exception to the permitted hours by non-City crews. At that time, the Committee asked
staffto review the hours of use around hotels. Staffmet with representatives of two downtown hotels
and agreed that Community Services and Public Works crews would coordinate their clean up efforts
around the hotels so that blowers normally would not be used until 7:00 or 7:30 a.m. Staff therefore
recommended to the Policy and Services Committee in September, that City crews be allowed to use
leaf blowers between 4:00 a.m. and 8:00 a.m. with consideration being given to areas directly adjacent
to hotels. At that time, the Committee directed staff to include the same considerations immediately
adjacent to residential properties. While staffbelieves this consideration could usually be given to the
cleaning of City streets and facilities that are adjacent to residential areas, it would be important to
CMR:412:99 Page 2 of 4
maintain some flexibility to deal with the change of routine schedules associated with employee
illnesses, vacations, etc. Staff therefore does not recommend a complete prohibition against theuse of
leaf blowers in these areas during the early morning hours.
Policy and Services Committee members also directed staff to study leaf blower use in commercial
areas that were not adjacent to residential and private properties. The Committee’s direction was
associated with regulation #6 that would allow commercial use of fuel-powered leaf blowers in
industrial areas on Saturdays between 10:00 a.m. and 4:00 a.m. Staffhas begun reviev~ing this concept
and believes that it xvould be possible to draft an ordinance that would be easily understood by
gardeners and Police staff. As an example, language could be drafted such that blowers would be
allowed within a certain distance from R-1 zones. However, there are some problematic issues
surrounding mixed-use areas of the City, which staffis still reviewing. Staffwill include more detailed
information and specific language at the time the draft ordinance is presented to the Council.
California Air Resources Report Update
Staff received a copy of the California Air Resources Board (CARB) draft report entitled "Potential
Health and Environmental Impacts of Leaf Blowers." This report (see attached) was requested by the
California Legislature. A second public hearing was held in E1 Monte, California on September 28,
1999 for the purpose, of discussing the draft report with the public. Because the report is still a draft,
the CARB has asked that it not be cited or quoted. The fin!l draft will be presented to the CARB
around November 11 and will be voted on at its meeting of December 9. After that meeting, the report
will be presented to the legislature.
Pending Legislation Update
There are three bills pertaining to leaf blower reg-ulations that were proposed during the first year of the
Legislature’s term that were held in Committee. Staff has learned that at least one of the bills will be
pursued when the Legislature goes back into session.
RESOURCE IMPACT
Estimated costs for implementation ofproactive enforcement are $43,000. If Council approves staff’s
recommendations, a Budget Amendment Ordinance would be prepared and presented to the Council
at the time a draft ordinance was agendized for Council consideration.
POLICY IMPLICATIONS
Staff’s recommendations are consistent with the Comprehensive Plan policy to evaluate changes to the
noise ordinance to reduce the impact of leaf blower noise (N61) and with Policy and Services direction.
CMR:412:99 Page 3 of 4
TIME LINE
Pending Council approval of the recommendations, staff will work with the City Attorney’s office in
the preparation of a draft ordinance. Staff anticipates this process will take about six months to
complete.
ENVIRONMENTAL RE’~qEW
An environmental determination would be made at the time a proposed revision of the current ordinance
is presented to Council.
ATTACHMENTS
CMR:352:99
P & S Meeting Minutes, September 14, 1999
California Air Resources Board Report and Executive Summary.
PREPARED BY:Lynne Johnson, Assistant Police Chief
REVIEWED BY:
APPROVED BY:
hief of Police
/
CMR:412:99 Page 4 of 4
City of Palo Alto
City Manager’s. Report
TO:
ATTENTION:
FROM:
DATE:
SUBJECT:
HONORABLE CITY COUNCIL
POLICY AND SERVICES COMMITTEE
CITY MANAGER DEPARTMENT: POLICE
SEPTEMBER 14, 1999 CMR: 352:99
REVISED RECOMMENDATIONS REGARDING THE USE OF
LEAF BLOWERS IN PALO ALTO
REPORT IN BRIEF
In February 1999, staffprovided recommendations for regulating leaf blowers to the Policy
and Services Committee. At that time, Committee members requested some additional
information and asked that staff address certain issues. Specifically, the Committee asked
that: an alternative to the City issuing permits be pursued; the recommended hours for
gardeners use of blowers be reviewed; additional consideration be given to areas around
hotels; staff work with the Bay Area Gardeners Association (BAGA) in certification and
training efforts; the use of blowers around residences begin at 6:00 a.m. instead of 4:00 a.m.;
consideration be given to requiring mufflers; and the recommended hours for homeowners
be reassessed. Additionally, the Committee asked that staffprovide information as to how
the acceptable noise levels of blowers would be determined, how information about
complaints would be reported to the Council, and why complaints about leaf blowers had
increased over the last few years. This report attempts to answer those questions and
provides revised recommendations that address the issues raised by the Committee.
RECOMMENDATIONS
Staff recommends that the Council direct staff to revise Chapter 9.10 of the Palo Alto
Municipal Code regulating leaf blowers in the following manner:
1)Allow only commercial gardeners/landscapers who are trained and certified by a City-
approved process to operate fuel-powered leaf blowers within the City limits;
2)Allow only leaf blowers (fuel and electric) with manufacturers’ affixed labels
indicating an American National Standards Institute (ANSI) noise level rating of 65
dBA or less at 50 feet to be used within the City limits
3)Encourage the use of leafblowers (fuel and electric) rate at 62 dBA or less by the year
2003;
4)Allow the use of fuel- powered leaf blowers between the hours of 8:00 a.m. and 5:00
CMR:352:99 Page 1 of 9
5)
6)
7)
8)
9)
10)
11)
p.m. Monday through Friday;
Allow commercial use of fuel-powered leaf blowers in industrial areas on Saturdays
between 10:00 a.m. and 4:00 p.m.;
Allow residents (and commercial gardeners) to use electric leaf blowers between the
hours of 8 a.m. and 6 p.m. Monday through Friday, and between 10:00 a.m. and4:00
p.m. on Saturdays and holidays;
Prohibit the use of all leaf blowers on Sundays;
Conduct enforcement on a proactive basis, utilizing citations and an increasing scale
as xvell as notification of violations to commercial gardeners’ clients at the location
of the violation;
Allow City. crews to operate leaf blowers between 4:00 a.m. and 8:00 a.m. in the
Downtown area, California Avenue area, Midtown area, the Municipal Golf Course,
and in City parking facilities, with special consideration given to those areas
immediately adjacent to hotels;
Exempt City crews from the regulations for clean up after special events and in
emergencies. ,
Prohibit City crews and discourage commercial gardeners from using fuel-powered
leaf blowers on Spare the Air Days.
BACKGROUND
Staff provided a list of recommendations regarding the regulation of leaf blowers to the
Policy and Services Committee on February 23, 1999. At that time, Committee members
asked that staff develop an alternative to the City issuing permits; review the hours of use
around hotels; review the hours City crews use blowers around residences; work with Bay
Area Gardeners Association (BAGA) in certification and training efforts; and reconsider the
hours for use by homeowners. Additionally, staff was asked to provide information about
how acceptable noise levels of blowers would be determined; how complaints would be
reported to the Council; and why complaints about leaf blowers had increased over the last
few years.. Since February, staff has been meeting with representatives of BAGA and the
California Landscape Contractor’s Association (CLCA), conducted a leaf blower
demonstration for the Council, completed additional research, met with representatives of
downtown hotels, and monitored legislative activities associated with leaf blower regulation.
DISCUSSION
Legislative Update
Four pieces of legislation associated with leaf blowers were introduced in Sacramento this
year. One resolution was adopted and three proposed bills are in committee.
Senate Concurrent Resolution Number 19 - This resolution was adopted in May 1999. The
resolution directs the California State Air Resources Board (CARB) to prepare and submit
CMR:352:99 Page 2 of 9
a report to the Legislature by January 1, 2000 that summarizes the potential health and
environmental impacts of leaf blowers and provides recommendations for alternatives to their
use. Specifically, CARB staffwill study exhaust emissions, noise, and blown dust associated
with leaf blowers. Additionally, the measure requests that local governing bodies refrain
from enacting any new ordinance that prohibits the use of leaf blowers until the CARB is
able to submit their report.
Staff has been contacted by the CARB representative who is coordinating th~ report.
Information from CMR: 139:99, the previous staff report on leaf blowers will be included
in its report. A public meeting was held in July in E1 Monte, California for the_purpose of
discussing the factual aspects of leaf blowers, soliciting additional information, and sharing
the methodology for conducting the study. Representatives of the CARB anticipate that their
report will be submitted around December 9 and that a public document will be available for
review by November 9. Staffwill continue to monitor the CARB’s progress as it prepares
its report, and will provide Council with updated information as it becomes available.
Assembly Bill 1544 - This bill would require local entities that propose to regulate
commercial use of leaf blowers to contract with an independent entity to perform an
economic assessment of the impact of the proposed ordinance. The bill would prohibit
ordinances that are adopted before January 1, 2000 that completely ban the use of leaf
blowers from being enforced unless approved by the voters of the jurisdiction. In June, the
bill was referred to the Environmental Quality and Legislative Government Committees.
Assembly Bill 1609 - Under this proposed bill, the Salvador Hernandez Lira Gardener Act
of 1999 would be enacted that would authorize local jurisdictions to establish a noise
limitation on leaf blowers of 65 dBA at 50 feet. The bill also provides that noise, levels of
less that 65 dBA be established by local agencies based upon testing by an independent
testing laboratory that more than one manufacturer sell leaf blowers in the state that meet the
proposed lower noise level standard. The bill would also prohibit cities and counties from
prohibiting the use of leaf blowers except between the hours of 6:00 p.m. and 8:00 a.m. on
weekdays and 5 p.m. and 9 a.m. on weekends. This bill has been referred to the Assembly
Committee on Environmental Quality.
Senate Bill 1267 - Senator Polanco introduced legislation that would prohibit leaf blowers
powered by engines that do not meet the CARB’s emissions standards or that are not in
compliance or labeled with noise level specifications established by ANSI from being sold
in California after January 1, 2001. The bill would prohibit cities and counties from
prohibiting or restricting commercial use of leaf blowers between January 1, 2000 and
December 31, 2001; would allow local agencies by ordinance to restrict the use of leaf
blowers that do not meet the ANSI standards after January 1, 2002; and allow a prohibition
on the commercial use of leaf blowers after January 1, 2002 by initiative. This bill failed
passage in the Environmental Quality Committee, but was granted reconsideration.
CMR:352:99 Page 3 of 9
Certification of Commercial Leaf Blower Users
Staff originally recommended that the City issue permits to leaf blower operators. Based
upon comments from the Policy and Services Committee members, staff has revised that
recommendation. Over the last four months, staff has been meeting with representatives of
BAGA and CLCA for the purpose of developing a certification and educational program for
commercial users of leaf blowers in Palo Alto. Both organizations currently provide training
for their members on the proper use and etiquette on leaf blowers operation. These
organizations have agreed to formalize the training for the purpose of certifying gardeners
to use leaf blowers in Palo Alto. The training would be coordinated by the City, in
conjunction with BAGA and CLCA and would be mandatory. The elements o{the training
would include the following: .~
Proper use of the blower and it’s efficiency when used in a responsible manner
Safety practices including the use of eye and ear protection
Use of the blower at the lower throttle positions and with extension tubes in place
Proper maintenance of the blower to ensure that appropriate gas-to-oil fuel ratios are
present to help reduce emissions ¯
Blower etiquette, including the prohibition of blowing debris onto adjacent properties,
streets, or public right-of-ways; and consideration for pedestrians and vehicles that are
in close proximity
A complete understanding of the ordinance and consequences of violations
Gardeners would be required to take a short written or oral test to determine their
understanding of the training. After completion of the training, the gardeners would be
issued a certificate of compliance that they would carry with them. In enforcement
situations, police staff would easily be able to determine whether a commercial gardener was
permitted to operate a blower in the City.
In order to ensure consistent training, BAGA and CLCA representatives have received a
commitment from the Coalition for Fair Legislation to provide funding in the amount of
$25,000 to $30,000 to pay for the production of a professionally produced training video.
Members of the Coalition include: BAGA, CLCA, Association of Latin American
Gardeners, San Mateo Gardeners Association, Lawn and Garden Equipment Dealers
Coalition, Outdoor Power Equipment Institute, and the Portable Power Equipment
Manufacturers Association. The video would be produced in Spanish and English. It is
probable that two versions of the video would be produced: one that is Palo Alto-specific and
one that is more generic that could be used in other cities.
All commercial gardeners, regardless of whether they are members of BAGA or CLCA or
not, would be required to be certified. Non-members of the organizations would need to pay
a nominal fee to receive the training and certificate.
CMR:352:99 Page 4 of 9
Staff proposes that the City provide assistance in the training and certification process by
providing overall coordination and oversight, printing the certificates, and helping to
publicize the training sessions.
:
Blower Certification- Sound Level and Emission Standards
Staff continues to recommend that blowers that are rated at 65 dBA or less at 50 feet using
ANSI standards be allowed for use in Palo Alto and that a manufacturer’s label indicating
the rating be affixed to all leaf blowers used in the City. While the leaf blower demonstration
conducted for the Council in May (Attachment A) revealed that sound levels of blowers were
measured at higher levels than the manufacturers ratings, the conditions unddr which the
measurements were taken did not follow the ANSI protocol. Staff determined that the ANSI
standards are the only-ones consistently recognized and used by federal, state, and local
governmental agencies. Almost all legislation regulating leaf blowers uses ANSI ratings as
the standards.
As an alternative, if the Council is uncomfortable with using the manufacturer’s label as
certification, the City could require that an independent laboratory certify all blowers used
in the City. However, it should be noted that the some of the makers of leaf blowers already
use an independent laboratory to conduct the tests to determine equipment ratings. As an
example, Maryama Company uses the Underwriter?s Laboratory for the testing of its leaf
blowers. Laboratories follow the established ANSI testing protocol when determining noise
level ratings.
Staff’~ original recommendations included one that within two years, only blowers that are
rated at 62 dBA or less at 50 feet be allowed for use in the City. After doing some additional
research, staff has changed that recommendation. While it is apparent that the companies
who make the blowers are moving towards equipment that would meet the 62 dBA rating,
it would be a substantial financial burden on commercial gardeners to purchase new
equipment after only two or three years. Therefore, staff now recommends that the City
encourage the use of blowers that are rated at 62 dBA, but that those rated at 65 dBA would
still be allowed for use for an additional three years, to 2003.
According to the Environmental Protection Agency (EPA) and the CARB, leaf blowers that
do not meet the Tier II standards (refer to CMR:341:98) that become effective after January
1, 2000 will not be allowed to be sold in California. Tier I! standards will lower hydrocarbon
emissions by about 70% over those allowed in 1995. The intent of the new standards is that
as older, non-compliant equipment that does not meet the higher standards wears out, users
will replace their blowers with those that do meet the new standards. Some companies are
already making blowers that will meet the Tier II standards.
It should be noted that most leaf blowers come equipped with factory-installed mufflers.
CMR:352:99 Page 5 of 9
Days/Hours of Operation
At the February 1999 Policy and Services Committee meeting, there was considerable
discussion regarding staff’s recommendations on the hours/days of week during which leaf
blowers would be allowed to be operated. Staff originally recommended that use of blowers
be allowed by both commercial operators and residents between 9:00 a.m. and 5:00-p.m.
Monday through Saturday and totally prohibited on Sundays and holidays. In discussions
with representatives of CLCA and BAGA, staff has revised the recommendations as follows:
Commercial use - Leaf blowers could be operated by commercial gardeners and landscapers
between the hours of 8:00 a.m. and 5:00 p.m. Monday through Friday. With the exception
of large properties in industrial and general manufacturing zoned areas, conirnercial use
would be prohibited on weekends. For those large properties in industrial and general
manufacturing areas, commercial use would be allowed on Saturdays between 10:00 a.m. and
4:00 p.m.
Homeowner/Resident Use - Staff recommends that residents (and gardeners) be allowed to
use electric blowers Monday through Friday from 8:00 a.m. to 6:00 p.m. and on Saturdays
and holidays from 10:00 a.m. to 4:00 p.m. Residents would be allowed to use fuel powered
leaf blowers during the same times and on the same days as commercial gardeners, (i.e.
between 8:00 a.m. and 5:00 p.m. Monday through Friday). Staff is recommending that
extended hours and dayi be allowed for only those residents who use electric leaf blowers.
The reason for this recommendation deals with enforcement. If residents were allowed to
use gasoline blowers at different times/days, police staff would need to determine whether
or not the operator was truly a resident. This sets up a situation that is not only labor
intensive, but also would be objectionable on the part of residents.
City Crews - Staff originally recommended that City crews be allowed to operate leaf
blowers in the Downtown area, California Avenue, Midtown area, the Municipal Golf
Course, and City parking facilities beginning at 4 a.m. At the Committee’s request, staff met
with representatives from the major downtown hotels and agreed that Community Services
and Public Services crews, including contractors, would coordinate their clean-up efforts
around the hotels so that blowers would not need to be used in the areas until 7:00 or 7:30
a..rn., and the green machine would be used more frequently in areas like Lytton Plaza.
However, staff does not believe that it is necessary to incorporate this agreement in the actual
ordinance.
For areas other than those adjacent to the hotels, the following alternatives were considered:
1)Prohibit City crews from use of leaf blowers prior to 6:00 a.m. - This alternative
presents significant problems, especially for cleaning City parking facilities and
sidewalk areas in Downtown and California Avenue areas. Vehicles begin parking
in lots and garages as early as 6:00 a.m. Additionally, pedestrian tra.ffic begins to
CMR:352:99 Page 6 of 9
2)
3)
increase between 6:00 a.m. and 7:00 a.m. The ability of City crews to efficiently and
safely clean these areas with pedestrians and vehicles present would be significantly
hampered unless done during hours when there is minimal vehicle and pedestrian
traffic.
Clean these areas every other week - This alternative is not recommended. Due to the
levels of activity in the Downtown and California Avenue areas, frequent and
consistent cleaning is needed. The accumulation of debris over a two-week period
would be unacceptable to business owners, residents, and visitors.
Hand sweep/rake these areas - While this alternative is an option, as reflgcted in CMR
139:99, the costs associated with it are considerable and as a result this alternative is
not recommended.
After a review of possible alternatives, staff still recommends that City crews be allowed to
operate leaf blowers between 4:00 a.m. and 8:00 a.m. in the designated areas with the
exception of the Downtown and California Avenue hotels.
Spare-the-Air Days - Staff has included a recommendation that would prohibit City crews,
including contractors, from using fuel-powered leaf blowers on Spare the Air Days.
Resolutions and ordinances have been passed in other jurisdictions that include similar
prohibitions. Staff also believes the City should strongly encourage commercial and
residential users from using all fuel-powered lawn and garden equipment, but feels
enforcement of a prohibition would be impossible, as Police staff would need to be able to
prove that the violator had prior knowledge of the designation of a Spare the Air Day. While
such designated days are widely publicized, it is definitely possible that a user would not
receive the information.
Proactive Enforcement
Staff continues to believe that proactive enforcement of a revised leaf blower ordinance will
assist in ensuring compliance and keeping complaints to a minimum. Because staff has
eliminated the permit concept, an increasing penalty assessment for subsequent violations
is recommended. As an example: the first violation would incur a $25 penalty; the second
violation a $50 penalty, the third violation a $100 penalty, etc. If Council approves this
approach, actual penalty amounts would be determined. This approach has been discussed
with representatives of BAGA and CLCA and they endorse it. Notification of the clients of
violators is also recommended.
Leaf Blower Complaints
At the Policy and Services Committee meeting, Council members asked for some additional
information regarding leaf blower complaints. Specifically, Council members asked why the
number c~f leaf blower complaints has increased over the last few years and how future
CMR:352:99 Page 7 of 9
complaints woUld be tracked. While there is no way of knowing for sure, staff believes
several factors have influenced the increased number of complaints. These factors include:
a higher sensitivity and awareness regarding leaf blower use; better documentation and
tracking of complaints; citizen’s knowledge that Community Service Officer (CSO) response
to complaints is usually more expeditious than police officers due to different levels of
activities; and a significant increase in the use of commercial gardeners in the City.
Staff would anticipate tracking leaf blower complaints as well as proactive enforcement
using the same methodology and system that is used now. As CSOs respond to complaints
or take proactive action, the information is communicated to dispatchers in the.
Communications Center and entered into a database. With the implementation of the
Computer Aided Dispatch system, this tracking will be significantly easier to do.
RESOURCE IMPACTS
In order to provide consistent proactive enforcement, an additional CSO wouldbe needed
to provide coverage seven days a week. Staffwould propose hiring a temporary CSO for the
initial enforcement efforts of a revised ordinance and, if warranted, return to Council with
requests for additional regular staff after a year’s experience. Estimated costs for the initial
implementation include:
Salary $40,000
Uniforms/Equipment 3,000
Total $43,000
If Council approves the staff recommendations, a Budget Amendment Ordinance (BAO) will
be prepared for these costs, as well as any costs associated with the training and certification
of gardeners. The BAO would be presented to the Council at the same time as the revisions
to the Municipal Code are adopted.
POLICY IMPLICATIONS
Staff’s recommendations are consistent with the Comprehensive Plans policy to evaluate
changes to the noise ordinance to reduce the impact of leaf blower noise (N61)
ENVIRONMENTAL REVIEW
An environmental determination would be made at the time a proposed revision to the current
ordinance is presented to the Council for adoption.
ATTACHMENTS
CMR:352:99 Page 8 of 9
Attachment A-Results of Leaf Blower Demonstration Conducted for the Council in May,
1999
Attachment B - CMR 139:99.
Attachment C - CMR 341:98
Attachment D - P&S Minutes, February 23, 1999
PREPARED BY:Lynne Johnson, Assistant Police Chief
REVIEWED BY:
APPROVED BY:
PATRICK DWYEaR, ~O’4Li~E CHIEF
CMR:352:99 Page 9 of 9
ATTACHMENT A
LEAF BLO’C,’ER PRODUCT DEMONSTRATION
Echo PB400E
(No rating)
74?75
77/76
81/80
81
Marayama BL 4500_SP
(Rated 62 DBA)
66/68
68/69
72/73
69/68
Echo 46LN
(Rated 65 DBA)
69/68
71/69
72/73
68/70
Stihl 320L
(Rated 70 DBA)
73/70
75/74
Stihl Electric
(R~ed 63 DBA)
62/64
64/65
Toro Electric
(No rating)
63/62
59/60
Stihl Vacuum
(Rated 69DBA)
66/67
69/70
Marayama (tube removed)
68/69
73/72
City Weed Wacker
77/76
77/78
Echo 46 LN (against fence)Echo 46 LN (fence tube oft3 ~reenMachine
67/68
72/73
71/73
72/73
69 idle
68/70 motion
Echo 46 LN (on cement)Echo 46 LN (cement no,,,tube)
70/69
74/75
72/71
74/73
Ambient 52
City of Palo Alto
City Manager’s Report
TO:
ATTENTION:
HONORABLE CITY COUNCIL
POLICY AND SERVICES COMMITTEE
FROM:DEPARTMENT: POLICE
DATE:
SUBJECT:
FEBRUARY 23, 1999 CMR:139:99
RECOMMENDATIONS REGARDING THE REGULATIONS
OF THE USE OF LEAF BLOWERS IN PALO ALTO
REPORT IN BRIEF
This report provides recommendations for regulating leaf blowers. As staff has conducted
research and talked to numerous people, it is clear that there are a wide variety of opinions
and p~rspectives on the issue. While the recommendations would not totally eliminate noise
level concerns and do not specifically alleviate the issue of particulate matter pollution, staff
believes it has devdop~d a balanced, proactive approach that should result in a reduction of
noise levels while at the same time maintaining an accepted level of cleanliness for the City.
This report provides updates on other cities’ experiences and summarizes the types of
regulatory legislation used by other agencies. The report also discusses proposed
enforcement procedures, addresses the issue of cleaning City properties and facilities, and
presents alternative options for Council consideration.
CMR:139:99 Page 1 of 18
RECOMMENDATIONS
Staff recommends that the Council direct staff to revise Chapter 9.10 of the Palo Alto
Municipal Code regulating leaf blowers in the following manner:
1)only leaf blowers that have been permitted for use by the City of Palo Alto may be
operated in the Cit3r,
2)permits would be issued, for a fee, only for blowers that meet the Califomia air
quality standards, and are rated at 65 dBA or less at 50 feet, by the American National
Standards Institute (ANSI);
3)
4)
in two years, permits would be issued only for blowers that meet the California
air quality standards, and are rated at 62 dBA or less at 50 feet, by the ANSI
standards;
leaf blowers must be operated with all extension tubes in place;
5)blowers could be operated only between the hours of 9:00 a.m. and 5:00 p.m.,
Monday through Saturday;
6)
7)
8)
use of leaf blowers would be prohibited on Sundays;
the blowing of debris onto adjacent properties would be prohibited;
enforcement would be conducted on a proaetive basis instead of a complaint basis.
After an initial grace period, citations would be issued for all violations. In those
situations when a commercial gardener is found to be in violation, a notice would also
be given to the gardener’s client informing them of the violation. If a leaf blower
operator receives two citations, the permit to operate the blower would be revoked.
9)City crews would only be allowed to operate leaf blowers beginning at 4:00 a.m. in
the downtown area, California Avenue, Midtown area, the Municipal Golf Course,
and in City parking lots;
10)City crews would be exempted from these regulations for clean up after special events
and in emergencies;
¯If Council approves these regulatory measures, staff would return with a draft of a revised
ordinance (Chapter 9.10). Additionally, staff would return with a budget amendment
CMR:139:99 Page 2 of 18
ordinance to cover the costs needed to implement the program. -
BACKGROUND
In January 1998, Council directed staff to identify and evaluate options for addressing leaf
blower noise, to review environmental issues, to provide a survey of what other jurisdictions
have done regarding leaf blowers, and to provide information about the current level of
enforcement and on issues related to .enforcement of any proposed ordinance changes.
Since that time, staffhas conducted a Considerable amount of research, held meetings with
gardeners and members of the public, obtained information about what other cities axe doing,
monitored local and state legislative activities, and performed noise level tests on equipment.
The two status reports provided to the Council during the.year (CMR: 216:98 and 341:98)
contain considerable information that is not repeated in this report. This report provides
updated information about the above topics, as well as costs associated with cleaning City
properties and facilities, alternatives for regulating the use of leaf blowers, and specific
recommendations for Council consideration.
Alternative Clean-up Tools
Staffhas investigated the types of.tools that are used for clean-up purposes and compared the
time it takes to do the work to the time doing the same work using a leaf blower. (It is
important to note that, while the mechanical tool in question is known as a leaf blower, it is
frequently used in the clean up of other debris such as litter, dirt, grass clippings, etc.)
Rakes/Brooms - The most commonly used tools for dean up of yards, open spaces, grounds,
etc., are rakes and brooms. Obviously, brooms are the quietest and result in the least amount
of pollution (some minimal pollution occurs when dust particles become disturbed during
sweeping and raking). Brooms, however, can only be used on certain types of flat, smooth
surfaces such as asphalt and concrete that are amenable to sweeping.
The time it takes to sweep an area is considerably longer than the time it takes using a
blower. Depending upon the reference source, the time differences range from three to five
times longer. According to industry standards published by the California Landscape
Contractors’ Association, a nonprofit organization that represents about 2,500 State-licensed
landscapers, there is an average ratio of one hour of labor using a leaf blower compared to
CMR:139:99 Page 3 of 18
five hours for sweeping. In 1997, the City of Santa Barbara conducted its own study
comparing times needed to clean parks with leaf blowers and sweeping. While the times
differed depending upon the amount and type of debris, weather conditions, the presence of
the public in the park, and the type of surface, they concluded that the average of one hour
of leaf blowing was equivalent to five hours of sweeping. In October 1998, one of Palo
Alto’s Public Works employees conducted a time comparison test. The employee used a
broom for one hour to clean the sidewalk area of University Avenue. He swept around tree
wells, along curbs and parking wheel stops. Using a broom, he was able to sweep
approximately two and one-half blocks on only one side of the street. Using a leaf blower
for an hour, he was able to clean a five-block area on both sides of the street.
Early last year, as the City of Santa Cruz was reviewing the use of leaf blowers in its city, the
city determined that the time needed to conduct the cleaning of its parking lots and other city
facilities without the use of leaf blowers would be two to three times longer.
Rakes are another tool that is frequently used. Rakes produce some noise when used on hard
surfaces (a metal rake on concrete was measured at 58-60 dBA at 50 feet) and result in
minimal air pollution. However, like brooms, they require additional time to complete the
work. An experiment was conducted by Echo, Incorporated. Echo is one of the largest
manufacturers of leaf blowers in the Country. It videotaped two men working side-by-side
in a park area. Each gardener was to clean a grass area covered with leaves. One gardener
used a rake and the other gardener used a leaf blower. The gardener who used the rake took
50 percent more time to complete the job.
Staff has heard on many occasions that a leaf blower ban adversely irnpaets the earning
potential of gardeners because it takes longer to do the work. However, to date, no
individual or organization has been able to provide any documentation that indicates that this
has proven to be the ease in those cities that have approved ordinances prohibiting the use
of leaf blowers. The California Landscape Contractor Association sent a survey to 1,000
members last Fall. One of the questions asked how much a ban on gas-powered leaf blowers
would increase their annual costs. Based upon the survey responses, the average increase
was 20.7 percent. The level of increase was found to be lower for larger businesses (16.6
percent) and higher for smaller businesses (22.3 percent).
Water- Water has been used in the past in many places to rid hard surfaces of debris. In non-
&ought years, hoses are frequently used in residential areasto dean driveways and
sidewalks. Some. cities, including Palo Alto, use power washers to dean their commercial
areas. This equipment generates noise levels that are as loud as or louder than leaf blowers.
Staffreeenfly took sound meter readings of a power washer being used in the downtown area
and found that it registered 73 dBA at 50 feet. While the use ofwater usually does not create
CMR:139:99 Page 4 of 18
air pollution problems, water is a resource that should not be wasted, especially during
drought years.
Other Tools - City staffhas reviewed the use of other tools, such as street sweepers, that are
frequently used to clean commercial areas. Sound meter readings were taken on the City’s
Green Machine, and on two models of street sweepers. Attachment A provides the results
of the sound meter tests taken at 3 feet, 25 and 50 feet. The Green Machine produced the
lowest noise; however, even at 50 feet, it produced up to 66 dBA, not much quieter than most
of the newest leaf blowers. While the Green Machine has been a useful tool in helping to
clean the downtown area, it has its limitations. Cement tire stops in parking lots, tree wells,
and other obstacles prevent its use in certain areas and restrict its ability to pick up debris in
certain areas.
New Technology
Manufacturers of leaf blowers have been contacted regarding the status of new technology.
Several things are occurring in this area. There is movement in the industry toward battery-
operated equipment. The major concern at this time is the quality, weight and cost of the
batteries. Initially, batteries could cost up to $600 and are quite heavy. While the potential
of battery-operated leaf blowers includes positive aspects in that they would not have any
fuel emissions, in all likelihood, they would still nm at about 63-64 dBA noise levels.
The potential of manufacturers to mass-produce leaf blowers that operate at 62-63 dBA
within the next few years is also quite good. Due to the logarithmic formula in determining
decibel levels, this means that leaf blowers could be operated at noise levels about 155
percent quieter than those used ten years ago and about 35 percent quieter than those
operated at 65 dBA. This would be equivalent to the noise levels of ears traveling on
residential streets (at 25 feet). According to manufacturer representatives, it is probably
unlikely that blowers would be made that would produce noise levels of much less than 62
dBA due to the considerable reduction in air flow, which would be detrimental to their
operation.
Staff has conducted some research and has done some sound level testing of some of the
newest equipment and determined the following:
The Echo PB46LN was tested and while it does not have the ping sound produced by
other blowers, the noise level was slightly higher in field conditions than its rating of
65 dBA.
¯Toro Proline BP6900 .claims to be rated at 62 dBA, but when tested by Police
CMR:139:99 Page 5 ef 18
Department persormel, was found to be slightly higher. It is quieter, however, than
the Echo PB46LN which is rated at 65 dBA.
The Maruyama BIA500 is advertised to be the quietest backpack currently made and
is rated at 62 dBA using ANSI standards. Staff was unable to obtain one to use for
sound meter testing however.
Ryobi manufactures a four-cycle blower that claims to produce 80 percent fewer
combined hydrocarbon and nitrogen oxide emissions than the traditional two-stroke
engines.
Staff was interested to learn that although more leaf blowers are sold in California than in
any other state in the Country, manufacturers are considering in the future not selling their
blowers here due tothe State’s stricter fuel emission requirements and the problems their
customers face with the various types of ordinances. Apparently due to the increased sales
throughout the rest of the United States, in addition to numerous cotmtries around the world,
the reduction of sales in California does not cause manufacturers much concern. While some
people believe that this trend may be the best possible answer to resolving the leaf blower
dilemma in the future, others are concerned that a general decline in the overall cleanliness
of the state will occur. ¯
T_vpes of Leaf Blower Re_malations
Staff has reviewed more than 45 ordinances from cities in California and found that leaf
blowers are regulated by different cities using various strategies. Cities develop regulations
according to their own specific needs and factors such as the amount of commercial and open
space areas located within their jurisdiction, the level of cleanliness their community
demands, and the amount of expenditures they determine acceptable for ensuring compliance ¯
to their regulations. Some cities do not regulate the use of leaf blowers at all. Regulatory
strategies fall into six basic categories: 1) time of day/day of week, 2) noise levels, 3) area
specific, 4) bans, 5) educational approach, or 6) a combination of the five.
Time of Day/Day of Week - These types of ordinances regulate by the times of day and days
of week that blowers can be operated. These regulations are the most common form imposed
by cities and are based on the premise that leaf blower noise is usually most offensive during
certain hours of the day or days of the week. Hour restrictions range from 7:00 a.m. to 9:00
p.m. Some cities totally prohibit the use of blowers on Sundays and holidays, while others
decrease the number of hours per day that blowers can be used on weekends and holidays.
CMR:139:99 Page 6 of 18
Ordinances using only time of day/day of week restrictions are fairly simple to enforce in that
it is obvious when the blowers are operated.
Noise Levels - Some cities regulate the use of leaf blowers based upon noise levels. These
types of regulations address one of the major complaints about leaf blowers which is the level
and type of sounds they produce. The decibel levels allowed by cities also vary, although
most use either 70 or 65 dBA limitations. Distances of measurement are consistently at 50
feet. Staff was unable to find any city whose ordinance required less than 65 dBA levels
(except for bans).
Ordinances that include noise level restrictions are not easily enforced as they require the
actual measurement of the blower. This method is time consuming for officers, and
gardeners can alter the noise levels by operating the blower at half-throttle, and with or
without the extension tubes. Additionally, these ordinances usually require the enforcing
agent to witness the blower being operated. This has been the primary reason that many
agencies, including Palo Alto, issue only warnings when decibel levels of a particular blower
are in question. Due to a number of variables, it is difficult to get any prosecution without
an officer personally observing the offender in action.
Area Specific - A number of cities have time and day of week restrictions for residential
areas, and no restrictions in commercial areas. As an example, Los Gatos allows use of leaf
blowers in residential areas between 8:00 a.rn. and 8:00 p.m. during the week, and between
9:00 a.m. and 7:00 p.m. on weekends and holidays. However, blowers can be used.anytime
in commercial areas. Los Gatos includes gasoline lawnmowers, and edge and hedge trinmaers
in their restrictions as well.
For those cities that have different restrictions for residential and commercial areas, it is not
uncommon to have distance requirements of 100 or 200 feet from residential zones.
Those agencies who have these types of ordinances report that they are fairly easy to enforce
as long as commercial and residential areas are well defined and easily identifiable by
officers without the need of zoning maps. The cities, like Palo Alto, where there are a
number of mixed use areas, present enforcement difficulties.
Bans - Some cities have adopted ordinances that include various types of bans. The range
of bans includes bans of all types of blowers to bans of only gasoline-powered blowers.
Usually, these types of ordinances have resulted in the greatest amount of debate and
controversy. The bans address the issues of air pollution and environmental concerns together
with.noise levels but are not favored by gardeners or owners of large comrnereial and public
properties.
CMR:139:99 Page 7 of 18
Enforcement feasibility is directly related to the specific language in an ordinance. As an
example, a prohibition of all types of leaf blowers is quite easily enforced. However, a ban
on only gasoline-powered blowers is harder to enforce as users can fairly easily convert them
to methane or other fuel-powered devices.
EducationalApproach - Some cities use ordinances predicated on the concept that individual
fights of users and community members in general should be considered and that blowers are
a useful tool if operated properly. These types of ordinances include user guidelines and
emphasize cooperative efforts between gardeners and community members in providing
education on the use of blowers that minimizes the noise levels and environmental issues.
For the few cities who use this approach, enforcement is almost nonexistent.
Combination - Many cities use a combination of the above approaches to regulate blowers.
Additionally, some cities have added additional types of restrictions in their ordinances.
These include the following requirements: leaf blowers must be muffled; extension tubes
must be used; blowers cannot be used for more than 10 to 30 minutes at one time; or only one
blower may be used at a time on one property parcel.
Depending upon the number and type of variables included in such combination ordinances,
enforcement is usually quite difficult due to the factors noted above.
Update: Other Cities’ Exp_ etienne
Staffhas continued to research what changes other cities have been making in regulating leaf
blowers. Attachment B provides an updated list, by city, of various types Of ordinances.
Previously, information had been received that Palos Verdes banned gasoline and electric
blowers. While that language still appears in Palos Verdes’ ordinance, in 1991, due to the
drought that was occurring at that time, an amendment was made to the ordinance that
allowed the use of leaf blowers that are certified by the City. Only those blowers that don’t
produce noise levels of more than 70 dBA at 50 feet are certified. As a result of the
amendment, the ban is not enforced.
In mid-August, the City of Los Angeles stopped enforcement efforts on its ordinance
(applicable only to residential areas) due to the dismissal by a Municipal Court Judge of
tickets issued to gardeners who were cited for operating leaf blowers using methanol fuel.
Because the ordinance only banned gasoline-powered blowers, and since it is very difficult
by either odor or visual obsercation to differentiate between gasoline or methanol,
enforcement was curtailed for a period of time. Enforcement efforts have begun again.
When a gardener claims to be using methanol, the inspector and police officer request a
.sample of fuel. Any samples that are taken are sent to a laboratory for analysis.
CMR:139:99 Page 8 of 18
Some cities have recently enacted’bans. They include Manhattan Beach (9/98) and Santa
Barbara (11/97).
In October 1998, the Santa Cruz Council conducted a study session on leaf blower regulation
alternatives. At that time, the Council directed that a task force of community members and
gardeners be formed to review the issue. The task force was developed and initial indications
were that it would recommend restrictions, but not a ban. In the interim, the membership of
the City Council changed. The issue of leaf blowers has been put on hold.
Sunnyvale held a noise forum last fall that addressed all types of noise issues. Based upon
the information received, recommendations most likely wilt be made to Sunnyvale’s Council
that leaf blowers not be singled out from other noise producing tools and that with the
possible exception of reducing the hours of the day that blowers could be used, no changes
be made to current regulations.
Staff has also received a copy of a court decision that was rendered in New York last
December that ruled that the City of Long Beach, New York’s ordinance prohibiting the use
of power blowers was unconstitutional. The ease involved two defendants, a landscaper and
an employee of the local school district, who were charged with violating that city’s four-year
old ordinance that prohibited the use of power blowers. The defendants moved for dismissal
of the charges on the grounds that the ordinance was arbitrary, exceeded reasonable
objectives and was unreasonably burdensome to their landscaping business and school
maintenance program.
Staff had originally planned on providing Council with evaluation of options last fall.
However, due to the Senate Bill that was pending at that time in Sacramento and the ballot
measure activity that were occurring in Menlo Park. However, staffbelieved it was prudent
to wait until after Menlo Park’s election and a conclusion was reached in the State capital
before requesting Council action. Menlo Park’s ballot measure was defeated and currently
a task force is reviewing options for regulating leaf blowers. Senator Polaneo’s bill died
during last year’s session after it reached the Committee on Environmental Quality. Staff
recently spoke to a representative from Senator Polaneo’s office and was told that he is
actively considering proposing a similar type of bill during this year’s session, but that a final
decision will not be made until mid or late February.
Pollution Issues
As described in CMR’s 216:98 and 351:98, in addition to noise levels, there are two
pollution concerns associated with leaf blowers, gas emissions and particulate matter.
According to the Environmental Protection Agency (EPA), most manufacturers of leaf
CMR:139:99 Page 9 of 18
blowers will be able to meet the new Tier II emissions standards that will become effective
next year. The EPA indicated that while electric equipment is cleaner than gas powered
engines, generating the power to r~n electric equipment does produce pollution as well. The
Bay.Area Air Quality Management District estimates that yard care equipment is responsible
for 2 percent of total pollution and that leaf blowers are only responsible for about 17 percent
of the pollution associated with yard care equipment. It has been estimated that using a gas-
powered leaf blower for one hour may be equivalent to 34 hours of driving a car; using a
chain saw for an hour may be equivalent to 63 hours of driving, and using a weed whacker
may be equivalent to 21 hours of driving.
The conclusions about particulate matter pollution are much less concrete and questionable
based upon the lack of creditable research and data.. In 1996, AeroVironment Incorporated
conducted a study for the South Coast Air Quality Management District to determine the
amount ofrespirable dust (PM-10) produced by leaf blowers. At that time, it estimated that
PM-10 emissions from leaf blowers contributed to about 1 percent of the total emissions in
the Los Angeles area.. It acknowledged, however, that it considered this a conservatively
high estimate that was based upon assumptions and unvalidated information. While it is
obvious that leaf blowers do add to particulate matter pollution, until more scientific research
¯ using valid information can be completed, it is notpossible to determine the extent.
Update: Palo Alto Enforcement
During 1998, police personnel responded to 175 leaf blower complaints, an increase of 30
compared to the previous year. Of those complaints, by the time the officer responded, the
person using the blower was not located in 67 or about 38 percent of the eases. Out of the
total number of calls, 107 were as a result of the blower being used before the currently
permitted starting time on weekdays and 11:00 a.m. on weekends.
Citations were issued on two occasions within the last four months. One was issued in the
downtown area for operation of a blower on a weekday prior to 9:00 a.m. Warnings had
been issue prior to the.citation being issued. The other citation was issued in a commercial
area for operating a leaf blower on a Sunday prior to 10:00 a.m.
Attachment C provides a history of the 1998 complaints by date, time of day and location.
.Proposed Re_malations and Enforcement
Opinions on the use of leaf blowers range from opponents who are concerned about noise
levels and pollution generation to proponents who cite leaf blowers efficiency, utility and
economy. Little consensus is shared between people who hold the divergent viewpoints. It
CMR:139:99 Page 10 of 18
is clear that regardless of Council’s final direction, some members of the community will not
be satisfied. With this in mind,, staff recommendations reflect efforts to approach the issue
with a balanced, proactive strategy that should result in considerable noise reduction while
allowing gardeners and others to maintain the cleanliness of the City.
Staffrecommends a decrease in allowable decibel levels of leaf blowers, further restrictions
in the permitted hours and days of operation and a change in enforcement procedures.
Staff has analyzed the information regarding the use of leaf blowers and determined the
following:
Leaf blowers (gasoline and electric) do produce noise levels that are-offensive and
bothersome to some individuals.
Leaf blowers (gasoline and eleelric) blow pollutants including dust, animal droppings,
and pesticides into the air adding to pollution problems.
Gasoline-powered leaf blowers produce fuel emissions that add to the air pollution.
Other garden equipment such as gasoline-powered lawn mowers, hedge trimmers, and
weed waekers also produce similar noise levels and present many of the same
environmental concerns.
While there are other types of tools that can be used, the majority of them require at
least 30 to 50 percent more time to complete the work compared to leaf blowers, and
thus significantly increase the costs to the City for clean up ofpublicfaeilities. "
Ordinances regulating the use of leaf blowers should be easily enforced and
understood in order to be effective and for compliance to occur.
Staff proposes changing the level of enforcement associated with the recommended changes
to leaf blower regulations from a reactive and complaint basis to a proactive basis. This
recommendation is made based upon the belief that compliance would be more apt to occur
if users of leaf blowers knew that the City’s approach was not complaint-based.
The con.cept of issuing permits, similar to that procedure used by Palos Verdes, provides two
positive elements. The first is ease of enforcement. As police staff travel around the city and
observe people using leaf blowers, it would be quite easy to determine a violation just by
visually inspecting the blower for an affixed permit. Prior to receiving a City permit, the
blower would be tested once by either City staff using a sound meter or a certificate of
compliance by an independent testing agency such as ANSI would be required. A
manufacturer’s certificate would not be accepted. Permits would need to be obtained for all
leaf blowers, including those used by residents on their private property.
Secondly, at the time permits are issued, City staff would provide education material
CMR:139:99 Page 11 ef 18
(bilingual) and instruction to users of blowers on the proper way to use thorn. As an
example, research revealed that when the extension tubes are used on blowers, they are
quieter than when used without the tubes. According to many sources, many independent
commercial gard .eners never receive instruction on the proper use of blowers. This type of
educational assistance would be beneficial in helping to ensure the appropriate use.
Staff is recommending that permits be issued only to those leaf blowers that meet ANSI
standards. The American National Standards Ins.titute (ANSI) is the coordinator and
administrator for the United States private sector voluntary standardization. Underwriters
Laboratories, an independent non-profit organization that has become a recognized leader
in product safety and certification uses ANSI standards when certifying leaf.blowers.
Staffbelieves that a stricter enforcement posture that would result in citations being issued
after an initial warning period would help to alleviate many concerns. Staff also recommends
some additional enforcement elements. These include provisions that after receipt of two
citations, the permit for the blower would be revoked. Also, staff proposes that the clients
of commercial gardeners who are found in violation of the ordinance would be notified in
order for them to take more ownership in the issue.
Currently, Section 9.48.040 of the Palo Alto Municipal Code prohibits the sweeping,
throwing or placing of dirt, debris, and rubbish onto sidewalks, streets, alleys and gutters.
Staff recommends strengthening this language by including a prohibition against blowing
debris into adjacent properties and adding the proaetive approach to enforce these
ordinances.
Ci_ty Use of Leaf Blowers
Currently, City crews and contractors use leaf blowers to clean City parking lots, downtown
sidewalks, tree wells, bike paths, tennis courts, parks, City Hall plaza, athletic fields, City
facilities, and the golf course. Public Works and Community Services staff compiled
information for each of these areas regarding the frequency these areas are cleaned and the
times of day the cleaning takes.place. Additionally, the costs to clean these areas using leaf
blowers has been determined and an estimation of increased costs should the use of leaf
blowers be prohibited. Attachment D provides the detailed information. Staff estimates that
the current annual cost of almost $500,700 would be increased by almost four times
($1,979,775) should City crews be prohibited from using blowers. These estimates were
based upon information received from the City’s contractors, cities that have implemented
leaf blower bans, and projections for in-house work.
The blowers used by City crews in the downtown area are the newer models that are rated
CMR:139:99 Page 12 ef 18
at 65 dBA. City crews who work in other areas of town use models that are rated at 70 dBA.
All City contractors are required to use blowers rated at 65 dBA.
The other issue relative to City crews using leaf blowers deals with the actual hours of use.
At the time the current ordinance was adopted, Council made a specific exception which
allowed for business district street and public parking lot Cleaning to occur between i 0:00
p.m. and 7:00 a.m. on weekdays. Council recognized that, due to the presence of vehicles and
pedestrians, it is difficult to clean these areas during the times that leaf blowers are normally
allowed to be used (9:00 a.m. to 5:00 p.m.). The permitted decibel level of the blowers used
by City crews and contractors, however, is at the same 75 dBA at 25 feet that is required for
daytime use. Over the years, staffhas received some complaints from peoplg living in the
downtown and California Avenue areas about the noise created by the blowers, especially
in the early morning hours, and street and sidewalk cleaning. The City crews make every
effort to keep .the noise levels down. Staff believes that the problems associated with
daytime cleaning are still present and as a result are recommending that some specific
exemptions for City crews in certain parts of the city.
~TERNATIVES TO RECOMMENDATION
Staffhas considered alternative options for dealing with the leaf blower issue and discussed
the pros and cons with the members of the public at the three community meetings. (See
attached CMR:341:98). These alternatives, together with the reasons staff has not
recommended them, are listed below for Council consideration.
Make No Changes to the Current Ordinance - Staff believes that changes to the
current ordinance are needed and as a result does not recommend this alternative.
While the combination of decibel level limits and hours/time of day is a more
effective regulation than just one or the other, as reflected in the complaint history
over the last few years, enforcement has not been effective for several reasons.
In order to determine whether a violation has occurred during permitted hours of
operation, the user must be observed by the officer. Additionally, decibel levels must
be measured. It is not uncommon for commercial gardeners to use different staff at
the same locations. A complaint may be received about a user one week and the
officer may determine a violation has occurred. Due to the procedure the Department
has used over the years, fast offenses result in warnings. The next week, another
complaint about the same location may be received, but the officers frequently find
another individual operating the blower.
CMR:139:99 Page 13 of 18
Another problcrn with enforcement of the current ordinance is created by the fact that
many complaints are made anonymously. As a result, by the time an officer arrives,
the violator has already left, has stopped using the blower, or has changed the throttle
level of the blower. Without additionalinformation by an actual witness, enforcement
is extremely difficult. ~
As noted in a prior staff report, the average amount of time spent on leaf blower
responses is about 30 minutes.
Complete ban on all leaf blowers - Staff does not recommend this alternative for
several reasons. As discussed previously, ifa ban on the use of leaf blowers were to
occur without any exemptions for City crews and contractors, the costs to maintain
the cleanliness of City facilities, parks, parking lots, etc., would increase from
$500,700 to approximately $1,979,775. The City would not be the only public agency
who would incur additional costs if a ban were implemented. Staffhas conferred with
representatives of the Palo Alto Unified School District and determined that some
years ago, it was forced to reduce its gardening staffby about 50 percent. As a result,
it is vital that it use leaf blowers in order to keep the campuses clean. It is diligent
about operating its blowers at half speed and has not received any complaints about
their use. Should a ban on leaf blowers be imposed, it would face the alternatives of
increased costs or accepting a lower level of cleanliness. ,
While staffhas been unable to find any documentation regarding the loss of economic
earnings fo~ gardeners in those cities that have banned blowers, there is no doubt that
clean up of all kinds takes more time without the use of blowers. Gardeners would
then be forced to charge higher fees in order to maintain their same level of income.
Other types of power garden tools produce noise.levels that are louder or as loud as
leaf blowers and that add to air pollution problems. While they do not necessarily
produce the same pitch as blowers, there are substantial indications that other types
of tools are as offensive as blowers. A prohibition against just leaf blowers seems
arbitrary. If Council desires to prohibit the use of leaf blowers, staff would
recommend the prohibition against other power garden tools, such as lawn mowers,
hedge trimmers, chainsaws and edgers.
Ban on Only Fuel Powered Leaf Blowers - While staff considered this alternative, it
is not recommended based upon several factors. While an ordinance banning all fuel
powered (gasoline, methanol, etc.) blowers would also be easier to enforce than the
current ordinance, staffhas learned that gardeners and other users of blowers in some
cities have attempted to circumvent the.law by giving the appearanee that electrical
CMR:139:99 Page 14 of 18
o
cords are attached to the blowers. Staffhas also be~n advised by officers from some
jurisdictions that have banned fuel powered leaf blowers that because officer~ still
must personally observe the violation in order for enforcement m occur, few citations
are actually issued. Gardeners in those cities have learned that they have at least a
three- to five-minute window in which m do their blowing prior m the time an officer
may respond. In many instances, that window of oppommity is even longer dueto the
low priority given to these types of calls for service in many cities. As a result, it is
not unusual for the gardener m have either left the location, or at the very least,
stopped using the blower prior to the officer’s arrival.
Because it would be extremely difficult for City crews/contractors _to use electric
blowers due to the lack of accessible power outlets in many of the areas cleaned, staff
believes the cost impact for this alternative would be equivalent to that in alternative
#1. While it is possible to connect these blowers to generators, the noise and fuel
emissions created by the generators are frequently worse than gas powered blowers.
There are also safety issues concerning the potential for electrical shock whe~ cords
come into contact with wet surfaces. Because of this hazardous condition, two people
are usually needed to operate an eleelric leaf blower, one to operate the blower and
one to ensure that the cord does not come into contact with water or other liquids.
Based upon sound meter tests, electric leaf blowers are as loud as or louder than
gasoline-powered blowers. While they do not emit harmful fuel by-products, they
disturb the equivalent amount of particles that add to air pollution concerns.
Allow the Use of Leaf Blowers Only in Commercially Zoned Areas - Staff also
looked at this alternative and identified some positive factors. As one example, this
alternative would permit City crews to use blowers in such areas as the downtown,
California Avenue, etc., and as a result, the cost irnpaet to the City would not be as
significant as bans. However, the primary reason staff has not recommended this
option deals with the difficulty in enforcement of such an ordinance. Police staff
would need to rely on City zoning maps in order to determine the designation of a
specific property. Additionally, there are a number of places in the City where
commercially zoned properties abut or are across the street from residential or other
designated types of zones. This would present problems in that a blower could be
legally used on one side of the street, but cause an annoyance on the other side of the
street: This would create confusion and frustration. Enforcement would be almost
as labor intensive as the current ordinance.
Further Restrict the Hours of the Day and/or Days of Week Leaf Blowers may be
Operated - As an example, allowable times could be reduced to 10:00 a.m. to 4:00
p.m. or use could be prohibited on weekends and holidays. Staffbelieves ordinances
CMR:139:99 Page 15 of 18
just restricting times and locations are confusing to users, difficult to enforce and do
nothing to address the noise level concerns. Under this option, if City crews were not
exempted, additional staffwould still be needed or contractors hired if the same level
of cleanliness was to be maintained. The amount of additional costs would be
dependant upon the number of hours and!or days of weeks that would be further
considered restricted.
Allow Leaf Blower Use Only by Private Citizens on Their Own Property - In addition
to the cost impact to the City for cleaning City facilities and properties, a regulation
such as this would be difficult to enforce. Officers would have to verify the identity
of the user and the ownership of the property. Additionally, it does not address the
noise issues that are of the greatest concern. Staffalso believes it unfairly targets the
commemial gardeners while allowing residents unlimited usage.
Other Ideas - During the public meetings, other ideas surfaced such as allowing leaf
blowers to be used only in increments of 15 minute periods and dividing the City into
different zones and allow blowers to be used in specific zones on certain days of the
week. Staff determined that the confusion on the part of users, together with the
difficulty in enforcing such regulations, make this an unrealistic approach to dealing
with the issue and as a result has not recommended it.
RESOURCE IMPACTS
Currently, three Community Service Officers (CSO) are assigned to the patrol division to
take minor accident and crime reports, handle abandoned vehicles, perform traffic control,
respond to noise complaints. Staffbelieves that with the extra work load associated with the
issuance of permits for leaf blowers, the provision ofproaetive enforcement, and in order to
provide seven-day-a-week coverage, some additional staffing would be needed. Because
information about the number of leaf blowers in the City that would require permits is not
known, staffwould propose to hire a temporary CSO. After gaining some experience with
the program, staff would evaluate additional staffing needs and if warranted, would remm
to Council with requests for additional regular staff. Estimated costs for the initial
implementation include:
Salary $40,000
Uniforms/equipment $ 3,000
Supplies, education
materials, permits $ 3.000
Total $46,000
CMR:139:99 Page 16 of 18
In staff’s recommendation, a fee for leaf blower permits would be charged on an annual
basis. While a specific amount has not been determined, staff anticipates that a fee in the
areaof about $10 would be reasonable and would assist in helping to offset the operational
costs of the proactive program. The fee revenue would be determined by the number of users
of leaf blowers who obtained the permits. Should Council approve the staff
recommendation, staff would return with specific recommendations for the amounts for
penalties that would be assessed against violators. Currently, the fine for violation of the
ordinance is $35, with a $69 penalty assessment for a total of $104.
POLICY IMPLICATIONS
Staff’s recommendations are consistent with the Comprehensive Plan’s policy to evaluate
changes to the noise ordinance to reduce the impact of leaf blower noise (N61). As stated
previously, staff’s recommendation does not significantly address particulate matter
pollution, but instead attempts to have a significant impact on the noise levels and tries to
balance the concerns of as many involved parties as possible.
ENVIRONMENTAL REVIEW
An environmental determination would be made at the time the proposed ordinance returns
to Council for adoption.
ATTACHMENTS
Attachment A - Results of Sound Meter Readings of Other Types of Equipment
Attachment B - Summary of Additional Cities’ Ordinances
Attachment C - History of 1998 Leaf Blower Complaints
Attachment D - City Cost Comparisons Ban/No Ban
CMR:341:98
CMR:216:98
PREPARED BY:Lynne Johnson, Assistant Police Chief
Don Hartnett, Police Lieutenant
CMR:139:99 Page 17 of 18
REVIEWED BY:
APPROVED BY:
PATRICK DWYER, CHIEF OF POLICE
CMR:139:99 Page 18 of 18
ATTACHMENT A
NOISE LEVELS OF ALTERNATIVE CLEANING EQUIPMENT
EQUIPMENT ’3’25’$0’
Power Washer 87 76 73
Green Machine 82 69 64/66
Elgin "Cross Wind" Street Sweeper 91 82 78
Elgin "Pelican" Mechanical Broom 91 81 79
Sweeper
Z ~Z Z
£. 3 = =.~.
0 0 r.~
Date
01-14-98
01-17-98
01-20-98
01-28-98
01-28-98
01-30-98
01-30-98
02-14-98
02-20-98
02-20-98
02-20-98
02-21-98
02-23-98
02-26-98
03-03-98
03-05-98
03-09-98
03-09-98
03-10-98
03-10-98
03-11-98
03-12-98
03-23-98
03-26-98
ATTACHMENT C
1998 HISTORY OF LEAF BLOWER COMPLAINTS
Time
7:29 a.m.
9:56 a.m.
7:19 a.m.
7:59 a.m.
11:55 a.m.
8:48 a~m.
4:11 p.m.
8:56 a.m.
8:45 a.m.
10:36 a.m.
10:51 a.m.
1:53 p.m.
7:58 p.m.
8:57 a.m.
7:44 a.m.
12:17 p.m.
8:14 a.m.
8:45 a.m.
7:42 a.m.
4:59 p.m.
6:22 a.m.
7:42 a.m.
3:43 p.m.
11:20 a.m.
Contact Made (CM) or
Unable to Locate (UTL)
CM
CM
UTL
UTL
CM
CM
CM
CM
CM
CM
CM
CM
CM
CM
Hundred Block of Reported
Leaf Blower Violations
700 block of Middlefield
1100 block of Hamilton
100 block of E1 Camino Real
300 block of Pasmer
800 block ofMoana Ct.
300 block of Cowper
500 block of Lincoln
1700 block of E1 Camino Real
200 block of Tennyson
1700 block of Emerson
3300 block of St. Michael
800 block of Miranda Green Ct.
100 block of Lytton
1800 block of Waverley
1300 block of Newell
600 block of Kingsley
300 block of Cttrtner
900 block of Amarillo
2800 block of Middlefield
500 block of St. Clair
100 block of California
1000 block of Colorado
700 block of Loma Verde
2500 block ofW. Bayshore
Date
03-27-98
03-31-98
00-02-98
00-05-98
04-10-98
04-14-98
04-17-98
04-25-98
04-26-98
04-2%98
04-28-98
04-28-98
04--28-98
04-29-98
05-03-98
05-06-98
05-06-98
05-07-98
05-10-98
05-11-98
05-13-98
05-13-98
05-15-98
05-17-98
ATTACHMENT C
1998 HISTORY OF LEAF BLOWER COMPLAINTS
Time
3:42 a.m.
7:41 a.m.
7:53 a.m.
3:32 p.m.
4:51 a.m.
7:27 a.m.
1:04 p.m.
8:44 a.m.
3:36 p.m.
1:51 p.m.
7:24 a.m.
7:30 a.m.
5:46 p.m.
6:18 a.m.
11:47 p.m.
7:33 a.m.
11:57 a.m.
8:57 a.m.
11:49 p.m.
8:28 a.m.
1:25 p.m.
1:39 p.m.
12:08 p.m.
11:22 p.m.
Contact Made (CM) or
Unable to Locate (UTL)
CM*
CM
CM
UTL
CM*
CM
CM
CM*
CM*
UTL
CM*
CM*
UTL
CM*
Hundred Block of Reported
Leaf Blower Violations
600 block of Arastradero
200 block of Palo Alto Ave.
700 block of Maplewood
600 block of Homer
400 block of University
300 block of Hamilton
500 block of Lincoln
3900 block of El Camino Real
600"block of Homer
4200 block of Wilkie
300 block of Bryant
200 block of Sherman
200 block of Curtner
400 block of University
300 block of Waverley
300 block of Portage
200 block of Grant
3800 block of E1 Camino Real
300 block of Waverley
200 block of Hamilton
2300 block of Tasso
500 block of Channing
200 block of Edlee
300 block of Waverley
ATTACHMENT C
1998 HISTORY OF LEAF BLOWER COMPLAINTS
Date Time Contact Made (CM) or Hundred Block of Reported
Unable to Locate (UTL)Leaf Blower Violations
05-25-98 1:50 p.m.CM 700 block of Sutter
05-27-98 5:19 a.m.CM*600 block of Waverley
06-01-98 8:12 a.m.CM 3500 block of Laguna
06-02-98 7:53 a.m.UTL 1200 block of Harriet
06-03-98 10:25 a.m.CM 3100 block of Waverley
06-05-98 1:48 p.m.UTL 1200 block of Wilson
06-11-98 8:39 a.m.UTL 3800 block of E1 Camino Real
06-15-98 7:36 a.m.UTL 100 block Middlefield
06-15-98 7:57 a.m.CM 1200 block of Newell
06-16-98 7:56 a.m.CM 2600 block of Birch
06-17-98 6:32 a.m.UTL 500 block of University
06-17-98 7:41 a.m.CM 3500 block of Arbutus
06-18-98 8:19 a.m.CM 3400 block of Ross
06-22-98 7:42 a.m.CM 700 block of Page Mill
06-22-98 3:40 p.m.IYI’L 700 block of San Antonio
06-23-98 7:42 a.m.UTL 700 block of Page Mill
06-23-98 7:40 a.m.UTL 200 block of Sherman
06-23-98 7:32 a.m.UTL 100 block of Middlefield
06-23-98 5:25 p.m.UTL 700 block of Northampton
06-24-98 7:38 a.m.UTL 700 block of Page Mill
06-25-98 8:16 a.m.CM 3800 block of E1 Camino
06-25-98 8:31 a.m.UTL 500 block of Center
06-26-98 5:54 a.m.CM 3300 block ofW. Bayshore Rd
06-27-98 1:35 p.m.CM 1500 block of Portola
ATTACHMENT C
1998 HISTORY OF LEAF BLOWER COMPLAINTS
Date
06-29-98
06-29-98
06-29-98
06-29-98
06-29-98
06-30-98
06-30-98
06-30-98
07-01-98
07-03-98
07-04-98
07-05-98
07-06-98
07-08-98
07-08-98
07-09-98
07-09-98
07-10-98
07-10-98
07-11-98
07-12-98
07-13-98
07-13-98
07-15-98
Time
7:30 a.m.
8:26 a.m.
7:40 a.m.
1:11 p.m.
9:01 p.m.
7:57 am.
8:28 a.m.
6:04 p.m.
7:30 a.m.
8:30 a.m.
11:31 a.m.
8:24 a.m.
8:40 a.m.
7:37 a.m.
7:27 a.m.
8:22 a.m.
8:40 a.m.
8:20 a.m.
2:48 p.m.
4:56 a.m.
7:19 a.m.
7:38 a.m.
8:34 a.m.
Contact Made (CM) or
Unable to Locate (UTL)
CM
UTL
CM*
CM
CM
CM
CM
CM
CM*
CM
CM
CM*
Hundred Block of Reported
Leaf Blower Violations
700 block of Guinda
3100 block of Manchester Ct.
700 block of Page Mill
200 block of Lowell .
200 block of Sherman
700 block of Page Mill
1 O0 block of Middlefield
500 block of Matadero
700 block of Page Mill
3700 block of E1 camino Real
400 block of Ruthven
3100 block of Alexis
100 block of Middlefield
200 block of Forest
700 block of Page Mill
500 block of Center
1300 block of Newell
11 O0 block of Greenwood
3300 block of St. Michael "
4200 block of MeKellar
1500 block of Page Mill
800 block of Hangmen.
3600 block of Whitsell
200 block of Forest
Date
07-15-98
07-16-98
07-17-98
07-18-98
07-22-98
07-23-98
07-23-98
07-24-98
07-25-98
07-27-98
07-28-98
08-03-98
08-03-98
08-03-98
08-04-98
08-05-98
08-07-98
08-11-98
08-14-98
08-14-98
08-17-98
08-17-98
08-18-98
08-18-98
ATTACHMENT C
1998 HISTORY OF LEAF BLOWER COMPLAINTS
Time
8:56 a.m.
8:23 a.m.
6:41 a.m.
7:15 a.m.
8:33 a.m.
8:13 a:m.
8:27 a.m.
11:11 a.m.
1:35 p.m.
7:34 a.m..
8:31 a.m.
6:47 a.m.
6:19 p.m.
7:46 p.m.
7:55 a.m.
6:37 a.m.
6:37 a.m.
8:09 a.m.
6:37 a.m.
10:45 p.m.
8:46 a.m.
11:55 a.m.
8:09 a.m.
3:27 p.m.
Contact Made (CM) or
Unable to Locate (UTL)
UTL
.UTL
UTL
UTL
CM
UTL
CM
CM*
UTL
CM
CM
CM*
CM*
CM
Hundred Block of Reported
Leaf Blower Violations
500 block of Arastmdero
1200 block of Newell
400 block of Cowper
3700 block of E1 Camino Real
400 block of San Antonio
1200 block of Newell
3800 block of Corina
100 block of Churchill
2700 block of Waverley
200 block of Hamilton
1200 block of Forest
400 block of University
700 block of Colorado
2900 block of Alexis
1200 block of Newell
400 block of University
400 block of University
1200block of Forest
500 block of Waverley
2300 block of Wellesley
1800 block of Emerson
4200 block of Wilkie Way
1200 block of Forest
2300 block of Middlefield
A’I’FACHMENT C
1998 HISTORY OF LEAF BLOWER COMPLAINTS
Date
08-21-98
08-21-98
08-21-98
08-24-98
08-24-98
08-24-98
08-25-98
08-25-98
08-25-98
08-27-98
08-27-98
08-28-98
08-30-98
09-04-98
09-06-98
09-08-98
09-12-98
09-15-98
09-16-98
09-17-98
09-18-98
09-23-98
09-23-98
09-25-98
Time
7:18 a.m.
8:51 a.m.
8:58 a.m.
6:39 a.m.
8:41 a.m.
8:59 p.m.
7:25 a.m.
1:33 p.m.
6:48 p.m.
10:56 a.m.
8:33 a.m.
6:31 am.
12:43 p.m.
7:46 a.m.
7:22 a.m.
8:31 a.m.
8:25 a.m.
7:12 a.m.
5:30 a.m.
4:23 a.m.
9:30 a.m.
9:42 a.m.
12:12 p.m.
8:03 am.
Contact Made (CM) or
Unable to Locate (UTL)
CM
CM
CM
CM
CM
CM
CM
CM*
CM
CM
CM
CM*
ClVI*
CM
Hundred Block of Reported
Leaf Blower Violations
400 block of Kipling
200 block of Scale
700 block of Garland
200 block of University~
3000 block of E1 Camino Real
2400 block of E1 Camino Real
2800 block of Middlefield
500 block of Charming
500 block of Arastradero
600 block of Channing
900 block of Hansen
400 block of University
600 block of Homer
2100 block of Greer
100 block of College
700 block of Emerson
900 block of Dennis
700 block of Colorado
500 block of University
400 block of University
500 block of Alger
100 block of Lincoln
300 btoek of Sheridan
1200 block of Forest
Date
09-25-98
10-02-98
10-06-98.
10-06-98
10-08-98
10-09-98
10-11-98
10-13-98
10-17-98
10-18-98
10-20-98
10-27-98
10-27-98
10-28-98
10-28-98
10-28-98
10-31-98
11-02-98
11-05-98
11-05-98
11-07-98
11-08-98
11-09-98
11-10-98
A’I~rACHMENT C
1998 HISTORY OF LEAF BLOWER COMPLAINTS
Time
5:18 p.m.
8:31 a.m.
¯ 8:06 a.m.
6:50 p.m.
7:52 a.m.
10:28 a.m.
3:13 p.m.
9:34 a.m.
8:17 a.m.
8:11 a.m..
6:29 a.m.
12:27 a.m.
7:49 a.m.
8:43 a.m.
7:47 a.m.
7:37 a.m.
1:25 p.m.
3:25 p.m.
8:42 a.m.
1:21 p.m.
12:01 p.m.
8:40 a.m.
8:35 a.m.
1:13 a.m.
Contact Made (CM) or
Unable to Locate (UTL)
CM
CM - citation issued
CM
CM
CM
CM
CM*
CIVI*
CM
UTL
CM
CM
CM
CM - citation issued
Hundred Block of Reported
Leaf Blower Violations
2000 block of Channing
600 block of Waverley
600 block of Emerson
800 block of Ross Ct.
1600 block of Edgewood
1900 block of Waverley
400 block of Forest
1000 block of Cowper
200 block of Rinconada
2900 block of Middlefield
200 block of Cambridge
Amtrack Depot - Uniyersity Circle
4100 block of MacKay
700 block ofLayne Ct.
100 block of Middlefield
900 block of Scott
2700 block of Waverley
300 block of College
1200 block of Greenwood
1200 block of Wilson
2700 block of Waverley
1700 block of Embarcadero
2200 bloekof Greer
Amtrack Depot - University Circle
Date
11-11-98
11-14-98
11-15-98
11-17-98
11-19-98
11-23-98 ~
11-24-98
11-24-98
11-24-98
11-27-98
12-03-98
12-08-98
12-09-98
12-14-98
12-16-98
12-17-98
12-26-98
ATrACHMENT C
998 HISTORY OFLEAF BLOWER COMPLAINTS
Time
5:25 p.m.
2:15 p.m.
11:23 p.m.
5:18 p.m.
8:51 a.m.
8:30 a.m.
8:32 a.m.
1:26 p.m.
3:55 p.m.
7:35 a.m.
12:28 p.m.
7:14 a.m.
7:50 a.m.
7:33 a.m.
8:47 am.
10:10 a.m.
2:59 p.m.
Contact Made (CM) or
Unable to Locate (UTL)
CM
UTL
CM
CM
UTL
CM
CM
CM
* = City employee or
City subcontractor
Hundred Block of Reported
Leaf Blower Violations
400 block of Meadow
200 block of Tennyson
3900 block of Middlefield
800 block of Richardson Ct.
1300 block of Greenwood
3100 block of E1 Camino Real
9.~ block 0f CowPer
300 block of High
2000 block of Oberlin
3700 block of E1 Camino Real
200 block of Edlee
2200 block of Birch
700 block of Middlefield
800 block of Webster
1800 block of Emerson
400 block of Forest
300 block of Ruthven
ATrACHMENT D
COMPARISON BETWEEN CURRENT CITY COSTS AND ESTIMATED
COSTS IF LEAF BLOWER BAN IMPLEMENTED
AREAS BLOWERS USED
1 / week
TIMES CURRENT
COSTS
ESTIMA TED
COSTS
CONTRACTOR
USED
City Parking Lots 11 p.m. - 7 a.m.$15,650 $31,300 Yes
Downtown
Civic Center
Cubberley
Misc. Parking Lots 1 / week I 1 p.m. - 7 a.m.$21,700 $,43,400 No
Bike Paths ] / week 9 a.m. - 3:30 p.m.$,4,100 $8,20~No
Dead Ends l / week 9 a.m. - 3:30 p.m.$2,250 $4,500 No
Downtown Sidewalks 3 / week 4 a.m. - 7 a.m.$8,000 $24,000 No
Tree Trirraning Varies 8 a.m. - 4 p.m.$12,500 $25,000 Yes
In-House Tree Trimming Varies 8 a.m. - 4 p.m.$12,500 $25,13(10 No
SUBTOTAL $76,700 $161,400
COMMUNITY SERVICES
AR.EASBLOWERSUSED
Tennis Cottrts
Downtown Tree Wells
Parks
City Hall Plaza
Other City Facilities
Contract Inspection
Athletic Fields
City Facilities - Higher Use
Golf Course
SUBTOTAL
FREQUENCY[
21 month
3/week
5 / week
3 / week
3 / week
5 / week
3 / week
3-5 / week
5 / Week
7/MES
9 a.m. - 4 p.m.
10 p.m. - 7 a.m.
9 a.m. - 3 p.m.
8 a.m. - 3 p.m.
8 a.m. - 3 p.m.
7 a.m. - 3 p.m.
9 a.m. - 3 p.m.
9 a.m. - 3 p.m.
6 a.m. - 3 p.m.
CURRENF
COSTS
$9,245
$9,125
$423,370
ESTIMA TED
COSTS
$21,500
:~227,500
$27,375
$1,818,375
CONTRACTOR
USED
Yes
Yes
Yes
Yes
Yes
No
No
No
No
[TOTAL [ $500,070[ $1,979,775I
City of Palo Alto
City Manager’s Report
TO:HONORABLE t:lTlr COUNCIL
FROM:CITY MANAGER DEPARTMENT: POLICE
AGENDA DATE: APRIL 27, 1998 CMR:216:98
SUBJECT: LEAF BLOWER ASSIGNMENT STATUS REPORT
This is an informational report and no Council action is required at this time.
BACKGROUND
In January 1998, Council directed staff to identify and evaluate options for addressing leaf
blower noise, to review environmental issues, to provide a survey of what other jurisdictions
have done regarding leaf blowers, and to return in 90 days with a report.* Council also
requested that staff provide infomutfon about the current level of enforcement and on issues
related to enforcement of any proposed ordinance changes. Since receiving the assignment,
staff has been gathering information needed to develop the options. This report provides
information that staffhas gathered to date regarding the following: a summary of the history
of leaf blower control in Palo Alto; experience of other cities and their leaf blower
ordinances; test results of sound meter readings for various types of leaf blowers and other
garden equipment; leaf blower complaints and current enforcement efforts; pollution
information; and pending legislation concerning leaf blowers.
Summary. of Leaf Blower Control in Palo Alto
In 1972, the City established noise standards with the adoption of Palo Alto Municipal Code,
Chapter 9.10. In 1986, as a result of numerous complaints about noise from equipment used
by gardeners and Pubfic Works employees and City conlractors, the Police Department
started to formalize its response and enforcement of the ordinance. At that time, after
conducting noise meter readings on 18 different pieces of commonly used equipment, it was
CM~216:98 Page 1 of 8
concluded that the noise ordinance was restrictive and needed to be reviewed for changes.
After a Counvil study session on the issue early in 1987, staff presented three options to the
Council spedfically related to leaf blowers, including: 1) a ban on the use of gasoline
powered leaf blowers, 2) a prohibition on the use of gasoline leaf blowers within 250 feet
of a single family or multiple family residence; and 3) a prohibition on the use of a gasoline
lest’blower exceeding 90 de~’bels at a distance of 25 feet between 10:00 a.m. and 4:00 p.m.,
Monday through Saturday, and total prohibition on Sundays and holidays. The Council
approved the third option with some modifications as an ordinance amendment. The
modifications included a reduction from 90 decibels to 82 decibels and a further reduction
to 75 dedbels aRer July 1, 1989, and a change in hours from 9:00 am. to 5:00 p.m., Monday
through Saturday, and from 10:00 ~.m. to 4:00 p.m. on Sundays and holidays. At the time
of the second reading of the ordinance amendment, there was considerable discussion
concerning a possible exemption for City crews who used leaf blowers to clean parking lots
during uighrdme hours due to the anticipated increase in costs and a decrease in the standard
of cleanliness. Direction was given to staff at that time to prepare a policy for purchasing
quieter equipment. In August 1987, Council approved an amendment to the noise ordinance,
which permitted the use of gasoline leaf blowers not exceeding 82 dec~els at 25 feet
(reduced to 75 decibels at 25 feet on July I, 1989) to clean City parking lots between the
hours of I0:00 p~n. and 7:00 am., Monday tlu-ough Friday. Additionally, Council directed
that all. potential vendors and bidders for City equipment purchases or City contractors
adhere to five noise emission criteria for consideration. The criteria included: the vendor’s
ability to comply with the City’s noise ordinance; written plans for reducing equipment noise
emissions in the future; current operating decibel levels of equipment used by the vendor;
the ability of the vendor to provide equipment designed to reduce noise; and the vendor’s
commitment to the "Buy Quiet" program sponsored by the National Institute of.
Governmental Purchasing.
A le~’blower control initiative was placed on the November 1987 ballot, which would have
prohibited the use of gasoline powered leaf blowers exceeding 70 decibels at 25 feet and
would have required nsers of leaf blowers to get written-certification from the Police
Department that the equipment was not able to produce noise levels in excess of 70.decibels.
During the time prior to the election, it was estimated by representatives of both sides of the
initiative that costs for homeowners and the City would increase by 20 to 30 percent. The
initiative failed by 3,333 votes.
Enforcement of Ordinance
The Police Department has enforced the ordinance regarding the use of leaf blowers on a
complaint basis for the last ll years. Calls received concerning leaf blowers are assigned
to a police or community services officer for investigation. Response to these calls falls
within the non-emergency response category and, depending upon other higher priority calls
CMK:216:98 Page 2 of 8
for service at the time, the calls are normally handled within one hour of the receipt of the
call. It is not uncommon for the users of the leaf blower to have left prior to the officer’s
srrival. Oftentimes, ffthe user is present, they will reduce the power of the equipment once
they see the officer arrive. While the current ordinance prohibits leaf blowers which
produce noise levels in excess of 75 decibels, without testing each piece of equipment at full
throttle with a sound meter it is not possible for the officer to det~wmine if they-are in
violation.
The majority of complaints associated with 1eaf blowers concern their use prior to the
permitted hours of opea’afion. Very few complaints have been received about their use after
the permitted time. Attachment A provides a listing of leaf blower complaints received by
the Police Department from January 1, 1996 through December 31, 1997; providing the
location of the complaint, and whether the officer was able to contact the alleged violator.
For the first offense, a written warning is issued to the user. The officer completes a noise
violation form and information is maintained by location, name of user, and the action taken.
It is extremely rare to encounter repeat offenders.. During 1996, the Police Department
responded to 123 leaf blower complaints; in 1997, the number increased to 145. It takes an
average of about 30 minutes for an officer .to respond, investigate and document a leaf
blower complaint.
Sound Levels of Equipment
The Police Department uses calibrated sound meters that meet the standards of the American
National Standards Institute (ANSI) to measure decibel levels. It should be noted that ANSI
ratings, that come with most leaf blowers are usually obtained by taking measurements in
controlled settings and at 50 feet that sound meter readings taken under field conditions
usually result in higher readings than the ANSI ratings.
In 1987, few, if any, gasoline powered led’blowers produced noise levels below 70 decibels
at 25 feet. Staff’has recently taken sound meter readings of various brands of gasoline and
ele~ic leaf blowers, other commonly used garden equipment, and for comparison purposes,
ambients of other areas. Attachment B provides a detailed listing of the results. Generally,
most gasoline powered leaf blowers produce less noise than earlier models, but still have the
capability of reaching the mid to high 80 decibel level. Electric leaf blowers tend to be
slightly less noisy, but not significantly so. Manufacturers are finally beginning to design
and distribute blowers with even lower noise emissions. As an example, the Echo 46LN
model used by City workers has the capability of emitting only 65 decibels measured at 50
feet per the ANSI testing standards. In field tests, depending upon the ambient and other-
factors, the equipment produces up to "13 decibels at 50 feet. As with other types of garden
equipment, there are four noise sources asso~t with leaf blowers of any type, the engine,
CMR:216:98 Page 3 of 8
air volume!flow (normally measured in cubic feet per minute), muffler and impeller.-
According to information received from nmnufacturers, for the models that produce only 65
decibels the engine noise is about the same as the air volume noise.
It i~ important to note because a logarithmic formula is used in calculating noise levels, a
blower that produces 70 decibels is actually one-fourttt as loud as one that produces 90
decibels. A change of three decibels is barely noticeable to the human ear while a five
decibel change is noticeable, but not dramatic.
In researching the issue, staffleamed that the way blowers are altered or changed also affect
noise levels. As an example, most blowers are equipped with removable tube segments.
While it is presumably easier for the user to use just the short tube, there ig a reduction in
noise levels when all the tube segments are attached.
The detemfination Of whether a noise source is annoying is not solely determined by the
decibel level. Other pieces of garden equipment .such as lawn mowers and weed trimmers
.cau produce the same decibel levels, but are not as annoying due to difl’e~m, ces in tone, pitch,
and/or duration of use. - ~ "
Pollution Issues
There are two pollution concerns associated with leaf blowers: gas emissions and
dust/polle~. The United States Enviromental Protection Agency (EPA) has estimated that
garden equipment accounts for five percent of the air pollution in the country. Exhaust
emissions from these engines contain hydrocarbons, nitrogen oxides, carbon monoxide,
carbon dioxide, and particulate matter. These emissions are ~e result of fuel and air.being
mixed and burned to produce the power needed for the operation of the engine. According
to the National Vehicle and Fuel Emissions Laboratory, evaporative emissions occur in
several ways. The majority occur during refueling and sp’filage. These types of emissions
are generally smaller compared to the hydrocarbon emissions. In an article from the Bay Air
Quality Management District, it was noted that a gasoline powered leaf blower emits as
much pollution hourly as a c, ar driven 100 miles, a lawn mower 50 miles, and a chain saw
200 miles. Because other gasoline powered garden equipment produces equivalent amounts
of exhaust emissions, the EPA has sd .dressed all types of equipment and lass not singled out
leaf blowers.
In June 1995, the EPA finalized the first national regulations affecting small gasoline
powered engines used in garden equipment. Phase i regulations became effective in 1997
and were expected to result in a 32 percent reduction in hydrocarbon emissions. Because
the Phase 1 regulations affected all new garden equipment manufactured after August 1,
1996, the full impact has not yet been detemfined. Currently, the EPA is working with state
~1V~216:98 Page 4 of 8
and industry re~semtatives to structure Phase 2 standards that would result in an additional
30 percent reduction below the Phase 1levels.
Staff is still in the process of attempting to gather information regarding dust pollution or
paniculate matter created by leaf blowers. While it is clear that airborne dust panicles are
factors in cardiopulmonary illnesses, little concrete information based upon scientific
analysis associated with blowers has been found to date. The hupetus behind the City of
Santa Monica’s ban was ~ related to the number of residents with immune deficiency
diseases and the senior population with respiratory illnesses.
Other Cities’ Experience
Staffhas checked with other cities regarding thdr enforcement of leaf blowers. Most cities
have ordinances similar to Palo Alto’s in that they attempt to control the use of leaf blowers
by regulating certain decibel levels, hours of permitted use and distances from residential
areas. Some cities have included such stringent distance requirements that the ordinance
actually serves as a ban. Los Angeles~ as an example; prohibits gasoline leaf blowers within
500 feet of a residential zone. After passage of the Los Angeles ordinance in 1996,
opponents went to court in an attempt to get the ordinance declared unconstitutional. Some
cities have considered bans (e.g. Palm Springs) but have decided against them for various
reasons. AI~ Santa Barbara’s City Council decided not to ban all leaf blowers, an initiative
was placed on the ballot and was approved by the voters last November. However, a similar
advisory ballot proposal was defeated in the City of Burbank. Attachment C shows those
cities that have adopted ordinances that totally ban leaf blowers. The majority of those cities
that have enacted a leaf’blower ban prohibit only the use of gasoline powered blowers; a few
others have outlawed gasoline, electric and battery operated blowers. Enforcement is uSually
done on a complaint basis and response is a low priority. Staffhas learned that in order to
circmnvent the language of some bans, people have changed the type of fuel they use from
gasoline to alternative fuels like methane. Because some blowers have the capability of also
being used as vacuums, some users also circumvent leaf blower bans by using the vacuum
capability to pick up leaves and debris.
Staffhas also learned tha~ depending upon the size of the city, without an exemption for city
crews, a decrease in the level of maintenance to city streets, parks, and facilities or an
increase in costs resulted when a total ban occurs. Industry standards Published by the
California Landscape Contractors’ Association and the National Parks and Recreation
Association use a ratio of one hour of labor using a leaf blower to five hours of sweeping.
Some cities have conducted their own time/motion studies and have concluded that
production rates vary depending upon the amount/type of debris, weather conditions, type
of surface, and the number of people occupying the area that is being cleaned. In 1997, the
City of Santa Barbara estimated that a change from leaf blowers to sweeping/raking would
CIviK:216:98 Page 5 of 8
increase costs to maintain its golf course, parks, downtown, and parking facilities by an
estimated $445,000 per year and about $120,000 in one-time costs for the purchase of newer
equipment. The City of’ Berkeley reported that by switching from leaf blowers to brooms,
its park maintenance costs increased without receiving commensurate increases in its
budgets, and the frequency, quality, and standards of maintenance have been reduced.
Berkeley also reports a significant increase of wrist, elbow and back injury Workers’
Compensation cl~im¢ and retirements since it has switched to brooms.
Several years ago, the City of Whittier completed an exhaustive time-in-use study that
compared time and costs associated with alternatives to the use of leaf blowers. It concluded
the following:
Area covered is 168,989 square feet:
Blower
Broom
Hose down
2.~ hours
282 hours
76 hours
18 hours
COST
$32.06
$4,018.50
$1,083.00
Walk behind vacuum $256.06
Pendin~ Le~slation
On February 13, 1998, Senator Polanco introduced Senate Bill 1651. This bill was initially
introduced with language that focused on gasoline powered.leaf blowers. It would require
the State Department of Consumer Affairs to establish a testing and certification program by
July I, 1999, that would govern permissible noise levels for leaf blowers and a trade-in
program for those blowers that do not meet the specified standards. All leaf blowers sold
after January I, 2000 would need tomeet a maximum noise level of 65 decibels at 50 feet.
The bill would permit homeowners to use non~g blowers on their own property after
January 1, 2000. Additionally, the bill would protn’bit local agencies from regulating the use
of leaf blowers except between the hours of 6:00 p.m. and 8:00 am. on weekdays and 5:00
psn. and 9:00 am. on weekends. Staff conl~1~l Senator Polanco’s office and found out that
the bill was introduced in reaction to the City of Los Angeles’ new ordinance that became
effective on February 13, 1998. Senator Polanco believes that reasonable statewide
regulation of leaf blowers represents public policy that is superior to the various conflicting
local ordinances. In the analysis of the bill, Senator Polanco estimates that a commercial
gardener’s costs would increase 20 to 40 percent. However, the Senator’s assistant indicated
CMR:216:98 Page 6 of 8
that this estimate was based on antidotal information. The bill was not passed at the first
hearing in the Senate’s Business and Professions Committee on April 13 due to the lack of
the required number of Senators in attendance. At that time, the language-was amended to
address leaf blowers in general without regard to power source. The amended bill was
reconsidered on April 21 and ftmher amendments-were made. The most recent amendments
include language that would require the State Department of Consumer Affairs to certify leaf
blowers as meeting a specified maximum noise level based upon data provided by
manufacturers. Additionally, the bill has been changed to allow local initiative measures
which contained more stringent requirements on the hours or manner of use of leaf blowers
to supersede the bill’s provisions. The bill failed passage in the first hearing of the Revenue
and Taxation Committee, but will be reconsidered.
Anticivated Additional StaffWork to be Comt~leted
Prior to returning to Council with some options for consideration, staff will complete the
research phase of the assignment With that information, meetings will be conducted with
residents, gardeners, and other interested parties to obtain feedback on the issues and on the~
pros/cons of alternatives. Staff will then finalize options and return to Council. Staff
anticipates the remaining work on the assignment to take about two to three months,
depending upon the input received at the meetings with various groups.
RESOURCE IMPACTS
When staffretm’us to Council with options, cost estimates associated with each option will
be provided based upon enforcement, as well as any resource impacts to City operations.
ATTACHMENTS
Attachment A:
Attachment B:
Attachment C:
Two-Year Histo.ry of Leaf Blower Complaints
Decibel Level Matrix of Garden Equipment
Other Cities’ Leaf Blower Ordinance Matrix
PREPARED BY:Don Harmett,Lientenant, Traffic Manager
¯ Lynne Johnson, Assistant Police Chief
CMR:216:98 Page 7 of 8
REVIEWED BY:Chris Durkin, Poli~e Chief ---
APPROVED BY:
CMR:216:98 Page 8 of 8
ATTACHMENT A
TWO-YEAR HISTORY OF LEAF BLOWER COMPLAINTS
Date
12’31-97
12-31-97
12-30-97
12-28-97
12-28-97
12-28-97
12-24-97
12-24-97
12-17-97
12-14-97
12-6-97
12-4-97
12-4-97
12-4-97
12-3-97
12-1-97
11-28-97
11-28-97
11-27-97
11-26-97
11-25-97
11-24-97
Contact Made (CM) or
Unable toLocate
(UTL)
CM
CM
CM
CM
CM
CM
CM
CM
Hundred Block of Possible Leaf
Blower Violations
400 block of Forest
400 block of San Antonio
300 block of I-Iigh
600 block of Homer
700 block of Rosewood
2000 block of Channing
3600 block of E1 Camino
Bryant @ Channing
400 block of Kipling
800 block of Middlefield
600 block of Homer
4100 block of Crosby Pl
100 block of Walter Hayes
2700 block of Middlefield
200 block of Waverley
700 block of Arastradero
4100 block of Crosby
900 block of Scott
600 block of Gilman
Moana Ct
200 block of Grant
300 block of ~r
11-20-97
11-20-97
11-07-97
11-04-97
11-3-97
10-30-97
10-30-97
10-27-97
10-26-97
10-24-97
10-23-97
-10-20-97
10-17-97
10-15-97
10-08-97
10-6-97
10-3-97
9-30-97
9-30-97
9-08-97
9-25-97
9-24-97
9-24-97
9-23-97
9-22-97
9-19-97
9-18-97
600 block of Bryson
300 block of Forest
4100 block of Baker ..
Birch @ C~om~
400 block of Kipling
Bryson @ Middlefield
00 block of University
400 block of Kipling
400 block of Lytton
1900 block of Wavarley
Bryson @ Middlefidd.
Sheridan @ F_.I Camino
Scale @ Webster
3700 block of El Camino
2300 block of St. Francis
400 block of Kipling
3600 block of El Camino
900 block of Waverley
00 block of University "
400 block of Alma
500 block of Channing
9-200 block of St. Francis
3500 block of Laguna
400 block of Addison
2200 block of Yale
3000 block of Middlefield
2000 block of Oberlin
9-16-97
9-15-97
9-14-97
9-13-97
9-10-97
9-9-97
9-7-97
9-3-97
9-3-97
9-3-97
8-29-97
8-29-97
8-25-97
8-23-97
8-17-97 ¯
8-13-97
8-8-97
8-1-97
8-1-97
7-29-97
7-27-97
7-27-97
7-22-97
7-17-97
7-16.-97
7-12-97
7-10-97
400 block of Lincoln
1500 block of Madposa
400 block of Guinda
1500 block of Escobita
2300 block of Webster
g00 block of Los Robles
4000 block of Middlefield
500 block of Everett Ct
Ruthven
100 block of Middlefield
1000 block of Forest
3200 block of Ramona
Kipling ~ Lytton
Curmer @ E1 Camino
500 block of Everett Ct
Webster @ University
00 block of University
3500 block of G-reer
Chm’elaill @ Bryant
300 block of Forest
100 block of El Camino
600 block of San Antonio
500 block of Charming
2000 block of Chining
700 block of Loma Verde
1400 block of Hamilton
300 block of Feme
7-9-97
7-7-97
7-7-97
7-6-97
7-5-97
7-4-97
6-27-97
6-27-97
6-25-97
6-24-97
6-21-97
6-19-97
6-18-97
6-16-97
6-12-97
6-10-97
6-6-97
6-5-97
6-4-97
6-2-97
6-1-97
CM
CM
unit canceled
CM
CM
P0rtola ~,,,Sequoia ....................
Torreya Ct
CM
300 block of Lytton
100bI0ck of El Camino
1900 block of Waverley
Forest @ Bryant
3300 block of Middlefield
400 block of Forest
4100 block ofPena Ct
g00 block of Lytton
3300 block of Hillview
Cowper @ Hamilton
700 block of Middlefield
900 block of Bryant
2000 block of Oberlin
900 block of Bryant
700 block of Colorado
Byron
2000 block of Oberlin
1400 block of Bryant
Forest @ criiman
5-30-97
5-24-97
5-24-97
5-21-97
5-16-97
5-15-97
CM
CM
CM
CM
CM
200 block of Edlee
Forest @ Gilman
300 block of Cowper
1700 block of Middlefield
4100 block of Middlefield
800 block,,,,0f University
5-14-97
5-14-97
5-14-97
5-12-97
5-9-97
5-9-97
5-1-97
4-23-97
4-21-97
4..18-97
4-15-97
4-3-97
3-30-97
3-27-97
3-24-97
3-22-97
3-21-97
3-20-97
3-14-97
3-10-97
3 -g -97
3-7-97
3-3-97
3-3-97
3 -2-97
3-1-97
500 block of ArastraderoCM
UTL
CM
UTL
CM
CM
CM
CM
CM
CM
CM
CM
unit
CM
CM
CM
CM
CM
CM
CM
3100 block of Bryant
300 block of Webster
2600 block of Marshall
300 block of Cowper
4200 block of Ruthelma
Cdlman @ Fore
600 block of High
200 block of Addison
00 block of University
4200 block of Ruthelma
2000 block of Channing
600 block of Glenbrook
3300 block of Hillview
600 block of Gilman
2700 block of Middlefield
500 block of Hamilton
400 block of Forest
Cowper @ Everett
Park @ Edlee
Guinda @ Homer
500 block of Hamilton
500 block of San Antonio
Bryant @ Kellogg
300 block of Lytton
1600 block of El Camino
100 block of Cowper
3-1-97
2-27-97
2-21-97
2-18-97
2-14-97
2-13-97
1-27-97
1-25-97
lr21-97
1-14-97
1-10-97
1-27-97
1-14-97
I-9-97
1-7-97
12-26-96
12-22-96
12-6-96
UTL
LrI’L
CM
CM
CM
CM
CM
CM
CM
CM
UTL
CM
CM
CM
CM
CM
CM
CM
CM
CM
CM
Hamilton @ Cowper
2000 block of Channing
Hamilton @ Lincoln
4100 block of El Camino
Louis @ Embarcadero
Bryant @ Churchill
400 block of Alma
Lincoln @ Webster
Channing @ Webster
Channing @ Cowper
Columbia @ Stanford
400 block of Alma
Channing @ Cowper
Columbia @ Stanford
Channing @ Cowper
300 block of Seale
400 block of Forest
3700 block of Wright
12-4-96 400 block of High
12-3-96 3800 block ob Magnolia
11-28-96 400 block of Coleridge
11-24-96 400 block of Hamilton
11-23-96 500 block of Hamilton
11-23-96 700 block of Channing
11-22-96 4100 block of Hubbart
11-20-96 700 block of San Antonio
11-14-96 Kingsley @ Webster
11-13-96
11-13-96
11-13-96
11-7-96 ¯
10-31-96
10-25-96
10-24-96
10-24-96
10-16-96
10-12-96
10-11-96
10-11-96
10-9-96
10-9-96
10-9-96
10-7-96
10-6-96
10-5-96
10-3-96
10-2-96
10-1-96
9-27-96
9-26-96
9-26-96
9-23-96
9-21-96
9-19-96
CM
CM
CM
CM
CM
CM
CM
UTL
CM
UTL
CM
UTL
UTL
CM
UTL
UTL
CM
CM
CM
CM
CM
CM
CM
CM
CM
(electric blower)
Forest @ Gilman
4200 block of Pomona
Ly~on @ Emerson
300 block of Seale
3200 block of Middlefield
4100 block of Sutherland
600 block of Glenbrook
3200 block of Middlefiel~
Forest @ Bryant
Bryant @ Forest
700 block of Sutter
500 block of University
Emerson @ Churchill
University @ Cowper
400 block of High
200 block of Cowper
1100 block of Hmnilton
500 block of Hamilton
Loma Verde@ Middlefield
Forest @ CRtman
2200 block of Wellesley
400 block of Fernando
400 block of Fernando
Hamilton @ CRlman
00 block of University
Lot J
200 block of Alma
9-16-96
9-16-96
9-13-96
9-12-96
9-11-96
9-9-96
9-4-96
8-31-96
8-30-96
8-27-96
8-26-96
8-16-96
8-14-96
8-9-96
8-8-96
8-8-96
7-27-96
7-18-96
7-17-96
7-13-96
7-10-96
7-5-96
7-3-96
7-3 -96
6-30-96
6-30-96
6-24-96
CM
UTL
CM
CM
unfounded
CM
CM
CM
CM
CM
CM
CM
CM
CM
CM
CM
CM
CM
CM
CM
CM
Hawthorne @ Cowper
400 block of Fcraando
Sheridan @ E1 Camino
Middlefield @ Loma Verde
400 block of Fcrnando
California @ Columbia
100 block of Heather
Colorado @ Middlcficld
400 block of University
3800 block of Magnolia
400 block of Fcrnando
Waverley @ Embarcadero
300 block of Bryant
200 block of High
Ash @ Orant
400 block of Grant
Oregon @ W. Bayshore
4100 block of Morals
300 block of University
800 block of Hansen
800 block of Hamilton
1900 block of Waverley
1100 block of Parkinson
800 block of San Antonio
Hamilton @ Cowper
400 block of Hamilton
900 block of Matadero
6-22-96
6-14-96
6-3-96
5-31-96
5-30-96
5-23-96
5-23-96
5-22-96
5-19-96
5-17-96
5-16-96
5-14-96
5-13-96
5-13-96
5-8-96
5-8-96
5-’/-96
5-6-96
5-5-96
5-3 -96
5-3 -96
4-29-96
4-26-96
4-26-96
4-24-96
4-23 -96
4-22-96
CM
UTL
CM
UTL
unfounded
UTL
CM
CM
CM
CM
CM
CM
CM
unit canceled
CM
unfounded
CM
CM
CM
CM
CM
CM
CM
500 block
Wellesley
700 block
of Center
@ California
of San Antonio
500 block of Lowell
I00 block of Emerson
College @ Ash
@ For=st
100 block of Heather
600 block of Wildwood
Emerson @ University
500 block of Lincoln
400 block of San Antonio
200 block of University
1500 block of Page Mill
Middlefield @ Homer
200 block of California
1900 block of Waverley
University @ Tasso
Alma @ Lytton
2000 block of Channing
1100 block of Greenwood
University @ Cowper
600 block of Guinda
500 block of University
North California
University @ Alma
"/00 block of Page Mill
4-17-96
4-16-96
4-11-96
4-1-96
4-1-96
3-28-96
3-25-96
3-19-96
3-14-96
3-12-96
3-12-96
2-29-96
2-26-96
2-22-96
2-14-96
2-10-96
2-9-96
1-25-96
1-22-96
1-12-96
!.1-10-96
1-10-96
1-8-96
I-6-96
1-6-96
1-6-96
I-5-96
1-5-96
UTL
unit canceled
UTL
CM
UTL
CM
CM
CM
CM
CM
CM
CM
CM
CM
CM
CM
CM
CM
CM
CM
CM
CM
CM
North California
Forest @ Waverley
Gilman @ Forest
Stanford @ Bowdoin
500 block of University
3200 block o£ Crreer
1400 block of Bryant
400 block of Hamilton
Everett @ Bryant
300 block of Forest
3600 block of E1 Camino
Columbia @ Stanford
700 block of Guinda
2200 block of Park
2200 block of Park
300 block of Curtner
200 block of University
Stanford @ Columbia
600 block of Channing
2000 block of Edgewood
2000 block of Bryant
400 block of Grant
400 block of Newell
Castilleja @ Mh’amonte
1700 block of El Camino
1500 block of California
1900 block of Waverley
3300 block of Alma
Company
ATTACHMENT B
DECIBF~ LEVEL MATRIX OF GARDEN EQUIPMENT
Model
Echo 388
Stihl 476
Echo 370
Company
SO’ dBa
rating
PB400E le.af blower
BR400 leaf’blower
PB46LN leaf’blower
PB46LN @ reduced power
PB400E (with elbow robe removed)
~’BPJ20L leaf’blower
BG75 hand held leaf’blower
BE55 electric leaf’blower
BE55 @ ½ power
electric leaf’blower
m~ leaf’rake on lawn steps
HRC216HXA lawn mower
HRC216HXA with blade off"
electric lawn mower
T260 line trimmer
GX22 line trimmer
old ele~ic line trimmer
CS3400 chain saw (small)
50’ field
test
25’ field
test
!757
65
n/a
n!a
69
69
65
3’ fidd
test
91-104
90-100
89-95
71-78
72-77
70-73
60-64
73 -79
72-75
62-72
66-68
62-65
61-63
58-60
68
Echo 85-88
Echo 91-104 ¯
Stihl 382 88-98
Stihl 377 88-96
Stihl 362.89
Sfihl 85
Roybi
79-84
82-84
73-78
s-72
79-84
78-80
73 -78
73 -77
70-73.
68-73
63-70
81
72
7O
77-79
77-80
67-70
81-88
Honda
Honda
Blk-Decker
Honda
Sears
Echo
75-82
93
62 86
62-63 81-84
72-76 94-98 "
71-74 92-97
60-61 80
75-82 99-106
Miscellaneous Noise Source
Loud dog barking at approximately 35 feet
Voices during city staff meeting
City Hall plaza at lunch time
Train arriving at University Ave station measured at 25 feet
Car going by on quiet residential street measured at 25 feet
Vehicle traffic at Alma & Churchill during heavy traffic
Car with bad muffler at Alma & Churchill
dBa’$
78-80
55-65
58-65
85-92
Inside a quiet house
From porch of above house
Back porch of above house (some freeway noise and wind in trees)
65
62-76
81
42
43
49
CFM is the cubic feet per minute of air produced by a led’blower. All measurements were rounded
down to the n~arest whole number. Field tests were conducted under circu~ces that an officer would
likely encounter, but do not meet the ANSI testing standards which require the use of a sound room or
stadium. All of the reded equipment is gasoline operated, unless otherwise noted. Sound measurements
of garden equipment varied based on the four 90 degree turns made by the operator.
TO:
City of Palo Alto
City Manager’s Report
FROM: CITY MANAGER
AGENDA DATE: AUGUST 10, 1998 CMR:341:98
POLICE
SUBJECT: LEAF BLOWER ASSIGNMENT- SECOND STATUS REPORT
REPORT IN BRIEF
In response to a Council assignment to identify and evaluate options for addressing leaf
blower noise and environmenl~l issues, staff has continued to conduct research, contacted
additional cities that have implemented blower bans, and has held some community otm’each
meetings to receive input on the options. This report provides an update on the research,
includes information re~ved from gardmen and community members about their ,on~ems,
ideas and suggestions, and status report on pending legislation. Staff will remm to Council
soon after Council’s vacation with specific recommendations.
CMtt:341:98 ..............................................Page 1 Of ~
This is an informational report and no Cotmcil action is required.
BACKGROUND
This report provides additional information on the Council assignment to evaluate options
for addressing leafblower noise, to review environmental issues, and to get commu~ty input
on potential impact associated with options. Specifically, this report includes updated
information on pending legislation, experiences of additional cities that have banned blowers,
and the process used and opinions obtained from the community. Staff anticipates
agendizing the item for discussion and action at the Policy and Services Committee meeting
of October 6. Due to the interest level on this issue, staff will include the third staff report
in the Council packet soon after the Council returas from vacation in order to allow for
wider and timely distribution.
DISCUSSION
Other Cities’ Experienc~
Staff has conferred with several other cities regarding their enforcement of leaf blowers.
Contact was made with the Cities of Piedmont, Lawndale and Del Mar. The City of
Piedmont implemented a ban on fuel-powered leaf blowers in 1990. One problem it has
encountered is that gardeners use gas-powered generators forthe electric blowers that are as
loud and create as many pollution problems as leaf blowers.
Del Mar adopted its ordinance banning portable, gasoline-engine blowers in 1989.
Its ordinance is enforced by code enforcement personnel and they respond to 15-25
complaints a month.
Lawndale just enacted its ordinance one year ago. They allow homeowners and gardeners-
with a business license to operate electric blowers. Its code.enforcement officers enforce the
ordinance and respond to about six complaints a week.
Due to the fact that over half of the cities thin have banned leaf blowers are much smaller
than Palo Alto and as a result usually do not have large commercial and industrial areas,
numerous city facilities/properties or vibrant downtowns, staff has contacted some of the
larger cities to determine how they deal with the cleanliness issues in these areas without leaf
blowers.
CMR:341:98 .................Page 2 of 7
Since ~dopting its ordinance, the City of Los Angeles has .received so many complaints that
it is in the process of adopting another ordinance that would give its code enforcement
pea’sonnel enforcement authority, as significant police officer time has been spent in dealing
with the number of complaints. The City of Los Angeles has also allocated $1 million to its
Depatmmnt of Water and Power to develop a battery-operated prototype leaf blower that is
quieter and as powerful as gas-powered blowers. Became city workers use brooms, many
meas of the city are not lean~ as ox°mx Due to its concern about the cleanliness of surfaces
such as tetmis, baskethall, and volleyball corms, additional efforts are made to keep them-
clean to eusttre safety and to protect the city from increased’liability claims.
The City of West Hollywood has used general relief workers who are on unemployment and
welfare to perform some of the extra manual labor that was needed when ~ts ordinance
became effe~ive in 1984. The cleaning of the fity’s large parking lots is contracted out and
the associated costs have increased, but a~tual figures were not available.
In response to the City of Menlo Park’s ban, a petition drive to put the issue to the vote of
the people was successful and it will be included on the November 1998 ballot.
The San Mateo County Board of Supervisors recently adopted a resolution that prohibits use
of any polluting garden and utility equipment by any County department or independent
contractors working for the County on"Spare the Air Days" or other days that the Bay Area
Air Quality District requests the public refrain from engaging in polluting activities.
Attachment A provides an updated list of cities that have banned leaf blowers.
Pending Le~slatiol~
Senate Bill 1651, that Senator Polanco inuoduced in February 1998, died in the Senate
Appropriations Committee due to the language that required the State Department of
Consumer Affairs to provide for certification of blowers. However, Senator Polanco has
amended Senate Bill 14, which Originally dealt with jury service, and substituted leaf blower
language in this bill. Senate Bill 14 had already passed the Senate with its original language
and is currently pending in the Assembly. If passed, SB 14 would: prohibit cities from
establishing noise limitations on leaf blowers emitting noise levels of 65 decibels or less at
50f .eet; prohibit cities from regulating leaf blowers except between 6:00 p.m.and 8:00 a.m.
on weekdays and 5:00 p.m. and 9:00 am. on weekends; allow cities to regulate the manner
and use of leaf blowers used to blow debris into sidewalks or gutters; require leaf blowers
used commercially after January 1, 2000 to be tested and certified by an independent testing
facility; and allow cities to adopt more sta4.ngent requirements~ on the hours or manner leaf
blowers may be used only through a ballot initiative approved by the majority of the voters.
Staff will continue to track this legislation.
CIVIR:341:98 Page 3 of 7
Staff has received information regarding associated pollution issues from the California
Environmental Protection Agency Air Resources Board (CEPARB), the Environmental
Protection Agency (EPA), the Bay Area Air Quality Management District, the Sacramento
Metropolitan Air Quality Management District, and the South Coast Air Quality
.Management Distric~
The EPA initially adopmd Tier I emission standards for utility engines (engines used in lawn
and garden equipment) in 1990 that were to have became effective in 1992. However, due
to a petition filed by the utility engine industry, the implementation of the standards did not
begin until 1995. Tier II standar& were originally scheduled to become effective in 1999;
the implementation of those standards.has been delayed until 2000. Under the Tier II
regulations, the emissions of hand-held equipment will be reduced by about 70 percent from
the 1995 standards. Attachment B details the difference in standards between the 1995 and
2000 regulations.
~s developed by the CEPARB some years ago revealed that the amount of particulate
matter that is emitted from a leaf blower is equivalent to the surface dust that might be
caused by the wind blowing on a paved road or about five pounds an hour per leaf blower.
They also noted that leaf blowers are frequently used to clear paved areas such as driveways,
parking lots, etc., and thus become "dim" blowers. In a 1991 report, the CEPARB
concluded that particulate matter can cause serious health problems, especially pulmonary
and respiratory problems. The California particulate matter standard that was adopted in
1982 is 50 micrograms per cubic meter in a 24-hour period. The national 24-hour standard,
adopted in 1987 (EPA is currently revising), is 150 micrograms per cubic meter, not to be
exceeded more than once per year averaged over three years. While most particulate matter
is emitted from motor vehicles, off-road engines or engines used for lawn and garden
equipment, including leaf blowers, are responsible for a certain’portion of this pollution.
However, the EPA and CEPARB do not single out leaf blowers as offenders,but include
all fuel-powered lawn and garden equipment such as mowers, chain saws, edge Izimmers,
etc.
EPAdocuments acknowledge that hand-held equipment is primarily powered by two-stroke
engines because, unlike a four-stroke design, two-stroke engines have more operational
capability and are significantly lighter than four=stroke engines. Two-stroke engines,
however, emit higher levels of hydrocarbons, carbon monoxide, and particle matter. The
EPA has also recognized the industry’s progress towards lowering emission levels is
."significant" and is being accomplished through relatively simple engine modifications. As
a result, the CEPARB concludes that the industry is on schedule with its research and
development efforts that will bring them into compliance with the Tier II standards.
CMR:341:98 Page 4 of’7
Communi _ty Outreach/Re~onse
After receiving considerable information from other cities and based upon staff research,
seven options were presented as a basis for the community outreach meetings:
2.
3.
4.
A ban on all types of leaf blowers.
A ban only on fuel-powered leaf blowers.
A ban on the use of leaf blowers except in industrial parks and commercial areas.
Further restrictions on the hours of the day and days of the week they are currently
allowed.
An ordinance permitting the use of leaf blowers that are certified that-they caxlnot be
operated at higher than 65 decibels at 50 feet and that are permitted by the City for
use in Palo Alto.
An ordinance allowing leaf blowers to be used only by private citizens on their own
property.
¯No changes to the current ordinance.
At each of the meetings smffhas conducted with the various interested groups, feedback on
the issues and the pros/cons of options have been obtained. Some additional ideas that were
presented at the meetings include:
The use of leaf blowers on "Spare the Air Days."
Divide the City into districts and allowing leaf blowers to be used in districts on
certain days of the week.
Conduct more educational outa’each to leaf blower users on’proper use.
Regulate leaf blower use based upon duration of time used (e.g., 15 minutes in an
hour).
Use mediation to settle issues between users/complainants.
Staff has met with" representatives from Echo Corporation, the largest manufacturer of
commercial leaf blowers in the Country. Additionally, "reformation from other manufacturers
has been collected. On ffune 10, staff held a meeting that was attended primarily by
gardeners and landscapers. Twenty-one people attended that meeting. The first generalI
commtmity meeting was held on June 17. Community members were notified of this
meeting in several ways. Letters were sent to each neighborhood association and to over 70
people who had voiced opinions via letter, e-mail, telephone or oral communications at
Council meetings. A notice was included in the City’s Web page and a press release was
issue& Twenty-six people attended this meeting. Another community meeting was held on
July 15. Staff especially invited residents and business owners who hired gardeners who
used leaf blowers, as this was one segment of the community that staffhad not heard from.
CMR:341:98 Page 5 of 7
Twenty people attended this meeting~ seven of whom had attended one of the previous
me~dngs. A~tachment C provides the unedited responses received m each of the meetings.
The opinions and perspeu’fiv~s about the u~e of le~ blowe~ ~d ~e appropriate co~e of
~ ~ ~ ~& &~ ~ ~. Some people ~ve ve~ s~ong fee~ ~t ~e o~y
~ve is w to~y b~ l~blow~ due to ~e noise md poHu~on issues. ~emhave
~ong fee~ ~at blow~ ~e a necess~ ~d to help keep ~e co~~ clem. ~ere
is gene~ ~~m ~t w~v~ ~afio~op~on h selecte~ it nee& to be e~ to
~d~d ~d ~o~, ~d ~ ~e CiW ~o~d a~ to ~e s~e ~afio~ ~
homeo~, g~d~en or b~esses.
Additional Staff Work to be Comn]eted
Staff’is ~g the res~ phase of the ~ssignment and in the process of" determining cost
impacts to the City for the various options. Additionally, using ~II the information obtained
from the community outreach, staff will develop recommendations for Council consideration.
In order to provide a wide and timely distribution of the staff report containing
recommendations to interested community members, staff will agendize the item for referral
to the Policy and Services Committee once the. Council returns fi’om vacation and agendiz~
the discussion at the Policy and services Committee meeting on October 6.
RESOURCE IMPACTS
Staff" is still in the process of estimating costs associated with the options.
A’I~I’ACHMENWS
Attachment A - Revised List of Cities Who Have Banned Leaf Blowers
Attachment B- EPA’s Hand-Held Equipment Emissions Standards
Attachment C - Unedited Responses From Community Meetings
PREPARED BY:Lymue Jolmson~ Assistant Police Chief
CMR.:341’198 ..................Page 6 of
REVIE~VED BY:
APPROVED BY:
CMR:341:98 Page 7 of 7
ATTACHMENT B
EPA’s BAND-HELD EQUIPMENT EMISSIONS STANDARDS
Year Displacement HC CO NOx PM
1995-98 Less than 20 4.0g/bhp-hr Ida
20o: - less than 50o:4.0 Ida
50o: and greater 4.0 n/a
2000 All 4.0 .25
220g/bhp-hr
120
50
6o0g/bhp-hr
600
3O0
130
HC- Hydrocarbons
CO - Carbon Monoxide
NOx- Oxides of Ni~’ogen
PM - Particulate Matter
g/bhp-hr - grams per brake-horsepower-hou~
AI’I’ACHMENT C
Leaf Blower ODtions - Gardener’s Meetino_ June 10. 1998
Complete ban on ell leaf blowers.
Pro~: None given
¯
¯
¯
¯
¯
¯
¯
¯
¯
would take more time to do the work
increase costs to customer/City
vacuums won’t work (corners)
no economic equivalent
quality of work suffers
aesthetic degradation
increase in repetitive motion injuries
raking disturbs top soil; causes soil erosion
arbitrariness: doesn’t take into account needs of all parties; quality of life for
everyone
precludes advancement of technology to resolve noise issues
¯newer equipment is much quieter
¯more homeowners can have a beautiful garden with use of blowers
¯increase in request/use of gardeners - seniors
¯clients opted for less services when prices would increase
¯3rd party intervention is the problem - should be between client and gardener
.OgIJgJl.~: Ban on only fuel powered leaf blowers.
Pros: None given
in 1.5 years, everything we knowabout 2 stroke engines will change
doesn’t take into account new generation of technology
generators aren’t GFi equipped - result - safety issues
electric blowers designed for homeowners use
commercial use - only 2 months
double noise issue - blower and generator
requires 2 people - one to handle cords and one to use blower
trip hazards created by cords (electric blowers)
pollution still occurs - uses power
electric shock problem
lack of access to plugs
can be just as loud
¯hatchet approach
Allow leaf blower use only in industrial parks or commercial areas.
Pros: None given
¯
¯
O
some types of commercial areas require quiet
mixed use becomesan issue
double-equipment needed for gardeners
commercial
enforcement could be an issue
who do both residential and
Further restrict the hours of the day and days of week leaf blowers may
be operated. (e.g. 10 a.m.-4 p.m., Monday-Friday)
Pros:
better than ban
when tube requirement added, this solves the complaint problem (San Mateo)
would beat peak hours for commercial
some clients prefer work done on weekend
gardeners need to work eight hours
¯use on Saturdays
¯use on Sundays isn’t significant; they do work holidays
Allow leaf blowers that cannot be op.erated at higher than 65 decibels
as certified by manufacturer at 50 feet and require permits issued by the
City..
Hilisborough uses this
would assist in recovery/identification of stolen blowers
would eliminate use of older units
easy to enforce
training could be mandatory
would help drive technology
¯some people might not maintain their equipment
¯65 dba now, few years 60 dba
¯companies (responsible) put down safe mulch
¯more particulate matter disturbed by vehicles
Allow use of leaf blowers only by private citizens for use on their own
property.
Gardeners could sell their old blowers
¯
¯
¯
problem for gardeners
most people in Palo Alto have gardeners
discriminates between
homeowners would tend to be noisier - older equipment - 1 week 15 minute
use compared . commercial use
noise level could go up if more homeowners used, especially Sundays
~: No change to current ordinance.
¯
¯
¯
¯
Hillsborough uses this
would assist in recovery/identification of stolen blowers
would eliminate use of older units
easy to enforce
training could be mandatory
would help drive technology
¯
¯
¯
manufacturers won’t be inclined to solve problem
hard to enforce
continued levels of complaint ¯
doesn’t resolve issue
if state passes legislation, current ordinance couldn’t be used
Other Ideas
divide City into districts - only allow use on certain days in certain districts to
coincide with garbage pick up days
¯ General Comments
¯would assist in education; some commercial clients have offered to provide
space
¯63% gardeners 2-5 employees; 21% gardeners 5-10 employees; 5.3%
gardeners’25 + employees
¯they are willing to .work with City
¯key is training on operation of blowers
¯taking leaf blower away from trade is equivalent to prohibit electric vacuums
in house cleaning
¯weather causes back-ups
¯people see constant blower use all day long
¯would rather work .with reasonable restrictions than not work at all
¯example: MP ban - he raised rates - lost 11 clients; these clients hired others
who do less quality work; 15-30% increase in fees
- another lost 7 clients
¯vacuums also disturb air - dust
brooms kick up dust
dust/particles accumulate without blowers - becomes issue with wind
force manufacturers to give training
50-60% belong to organization; is increasing
multi-language handouts for training
Brands of Leaf Blowers
¯Echo - newer models are heavier
¯Stihl- 320L
¯Red Max
¯Astron
¯Shindawa
Leaf Blower o_otions - Community Meetino June 17. 1998
Complete ban on all leaf blowers.
¯
¯
¯
¯
¯
¯
¯
annoyance to bicyclists as debris blown into streets
budget
only option that addresses problem of pushing debris from one place to another
20 other cities have a ban - no cost increases
easy to understand
easy to enforce
removes noise, pollution issues associated with blowers - addresses health
problems
would put pressure on industry (garden equipment, not just blowers)
¯
¯
¯
¯
¯
¯
unless PA bans them like other adjacent cities; PA will become e mecca for
blower use
only totally pollution-free option
blowing removes valuable topsoil/mulch ~
alternatives provide more exercise, more jobs
less risk to gardeners
more fair as neighbors aren’t disturbed
have proven effective in other communities
¯
¯
¯
¯
¯
would remove a useful tool from gardeners
all tools have a cost associated with them
people on limited income would have a hard time affording gardener service
is arbit.rary
singles out one tool
¯2 stroke engines the problem
Ban on only fuel powered leaf blowers.
¯
¯
¯
¯
possibly quieter
good compromise, better than no ban at all
reduced fuel emissions
have proven effective in other communities
best electric blowers are cheaper than gas powered
¯
¯
¯
¯
¯
¯
¯
dust still gets blown around
electric blowers can be just as noisy
still removing organic topsoil
generator noise can be very loud
still have impeller that creates noise
shock hazard in wet areas
still could be hard to enforce as people can’t differentiate between noise of gas
vs electric
¯takes less time with gas powered so noise isn’t heard for as much time
¯if you water surface prior to blowing, only leaves get blown
¯battery powered electric broom is quieter
Allow lea~ blower use only in industrial parks or commercial areas.
Pros: None given
¯
¯
¯
¯
¯
discriminatory based upon areas
mixed use, people live in commercial areas
even workers deserve peace and quiet
noise could result .in loss of worker productivity
often encourages use in verY early or late hours
Further restrict the hours of the day and days of week leaf blowers may
be operated (e;g., 10 a.m.- 4 p.m., Monday-Friday).
Pros: None given
¯
¯
¯
¯
¯
¯
unenforceable
stiil impacts sleeping babies, people who work at home, seniors, ill people
would concentrate emissions/noise into shorter periods - more harmful
still have noise, pollution
unfair to those at home
would be unfair to residents who do their own work on weekends
Allow leaf blowers that cannot be operated at higher than 65 decibels
as certified by manufacturer at 50 feet end require permits issued by the
City.
based on noise standard, not on single piece of equipment
could provide an educational component (could track # of complaints to revoke
if too many)
certification by manufacturer is like fox guarding hen house
noise level still too high
some lots only 50’ wide
still takes time to enforce
¯ hard to measure leaf blower annoyance in decibels - pitch the issue
cost of administration, issuance of permits
dust pollution still a problem
not a good use of police resources
Allow use of leaf blowers only by private citizens for use on their own
property.
would result in overall less leaf blower use
unenforceable - proof of ownership
still creates noise, dust, emission problems
could result in neighbor conflicts
could put some gardeners out of work
~llJgILt~: No change to current ordinance.
None given
¯
¯
¯
¯
¯
use all comments from other options
police officers don’t always have noise meters
would cause more irritation
would make it difficult to deal with other noise issues
has loophole of alternate fuels
¯begs question on how it is enforced
¯ordinance might not be the problem, but enforcement of it
Other Ideas
San Mateo County
county operated equipment
not allowed to use on "spare the air" days
adopted purchasing guidelines
Bo
covers county contractors
Educational outreach needed
Mediation could be an option
Regulate by duration of noise (time used - e.g~, 15 min in an hour)
General Comments:
¯ ¯needs to be evaluated in context of all noise, e.g., Caltrain, highway
¯would like to see the complaints info mapped - may not be e I~roblem in all
neighborhoods
¯decisions shouldn’t be based just on the # of complaints - some people don’t
complain
¯ask the question - what are leaf blowers trying to do
¯current ordinance hard to enforce ¯
¯gardeners who don’t use leaf blowers are efficient and effective
¯if Council bans blowers for residents, should ban for City use
¯people who use blowers (City workers in parks) wearing hearing protection
¯noise harmful to especially children
¯pOlice enforce all sorts of bans, illegal activity
¯use of police to enforce noise not a good use
¯responsibility should be on homeowners who hire gardeners who use leaf
blowers
¯LA green card - English and Spanish
¯use water instead
¯people can chose to pay more or-have reduced level of cleaning
Leaf Blower Meeting - July 15, 1998
J~glkZO_.~: Complete ban on eli leaf blowers.
¯
¯
¯
¯
¯
¯
¯
¯
¯
¯
o
More gardeners would be needed so more gardeners would be employed.
Conflicts with .peacefulness associated with "gardens."
Is enforceable.
Promotes clean/healthy air.
More peaceful community.
Protects gardeners.
Improves quality of life,
Helps people who work at home; noise ar’fects productivity.
Two cycle engines add to global warming.
in downtown areas, businesses get dirty, cars get dirty with dust blown up.
Experience of cities who have banned no increased rates/less pollution.-
Used to clean sidewalks, lots, not just yards. Increases liability for land owner.
Ban in commercial areas would increase maintenance costs, cost to land~
owners/tenants; rents would increase.
May result in lawsuits to City by employees due to injuries.
Commercial properties would be impacted more as they have larger problem.
People working at home who object .could lead to cost increases for everyone.
Blowers help to get rid of dust and have it carried away by gardeners.
D.I;Zlig1L2: Ban on only fuel-powered leaf blowers.
Would eliminate gas emissions.
Makes a hum, not a screech; more palatable.
Cost to gardeners is less for ecluipmentlmaintenance.
Air pollution still a problem healthwise.
Top soil disturbed in yards.
¯
¯
¯
¯
¯
Electric blowers can be louder or as loud.
Pollution created through use of electricity.
Risks when used around pools, water, tripping.
Re~iuires two people to work cord and blower.
Hazard on larger properties with extension cords; some homes don’t have
electrical outlets.
GeneratQrs are noisy (used for electric).
Units used by gardeners are just as costly as fuel powered.
J~tJgJ:~: Allow leaf blower use only in industrial parks or commercial areas.
Would allow for cost-effective cleaning of large areas.
For commercial properties, they are economic necessity.
¯
¯
¯
¯
¯
¯
-o
¯
Not fair to adjacent residential neighborhoods.
People in businesses need quiet too.
Puts out even more air pollution.
Harm to user of equipment.
Issue of mixed use would pose a problem.
People on fixed incomes may not be able to afford gardeners.
Increased costs for some users.
Hard to enforce.
Further restrict the hours of the day and days of week leaf blowers may
be operated (e.g., 10 a;m. to 4 p.m., Monday through Friday}.
Alternative:Prohibit Saturday-Sunday-Federal holidays for commercial use. Should
apply to the City of Palo Alto.
Better than complete ban.
Nurses, police officers sleep during the day - would help them.
Unfair to people who work at home.
Still hard to enforce.
Increased costs due to decrease in working hours without any real benefit.
Unfair to everyone at home - more people work at home,
Most complaints come in early in the morning.
Allow leaf blowers that cannot be operated at higher than 65 decibels
at 50 feet and require permits issued by the City.
¯
There are different skill levels for gardeners. Some don’t know how to properly
use, Education component would change this,
Would keep prices down.
Easier to enforce as only a few blowers would qualify.
¯Not workable - people will ignore.
Allow use of leaf blowers only by private citizens for use on their own
property.
~.rJ~: None given
Unfair - neighbor might have old noisy blower.
Unrealistic as many residents hire gardeners.
No change to current ordinance.
No change would be simple.
Vast majority of residents don’t complain.
All cons from other options.
Not working now.
Other Ideas
A.Divide city into,zones - use 0nly one day in a zone.
¯Coincide with trash pick up.
Scheduling difficulty for gardeners
People who live on border of zones would get two days a week.
B.License all gardeners beyond business license (state or local). Would have
educational requirements; require certain number of hours of schooling and-
mandate membership in professional association.
Would raise competence level of gardeners.
Would need to be a state license so gardeners don’t have to h~ve multiple
licenses.
Not practical. "
Difficult for independents.
General Comments
¯Alternatives to leaf blower could also have some air pollution problems.
¯We don’t know how much particulate matter is stirred up in air in Palo Alto
with blowers.
¯No one talks about banning lawn mowers and they make just as much noise.
¯Some places in town have different levels of use - 20 times in 5-day period.
¯Mixed use in City would be hard to differentiate between
residential/commercial.
Not used just for leaves.
Tighter hours, more stringent limits, stronger enforcement would help.
Each option should be reviewed closely on enforceability.
Enforcement should not pit neighbor against neighbor.
Gardeners should be paid more if they don’t use blowers.
Study needs to be done to see difference in air pollution between fuel/electric
-powered.
¯When compared to trucks, planes, cars, leaf blowers not a real issue.
¯Blowers help to keep city beautiful,
¯
¯
¯
¯
¯
Beauty disturbed.
Abuses should be handled by neighbors/gardeners association.
OSHA requires respirators/hearing protection for users.
Consideration for other people must be considered.
There are different skill levels of users.
Leaf blower has been singled out to be banned - there must be a reason.
Leaf blowers benefit the few at the expense of many.
TO:
City of Palo Alto
City Manager’s Report
HONORABL£ city COUNCIL
FROM:CITY MANAGER DEPARTMENT: POLICE
AGENDA DATE: AUGUST 10, 1998 CMR:341:98
SUBJECT: LEAF BLOWER ASSIGNMENT -SECOND STATUS REPORT
REPORT IN BRI!~F
In response to a Council assignment to identify and evaluate options for addressing leaf
blower noise and environmental issues, staff has continued to conduct research, contacted
additional cities that have implemented blower bans, and has held some community outreach
meetings to receive input on the options. This report provides an update on the research,
includes information received from gardeners and community members about their concerns,
ideas and suggestions, and status report on pending legislation. Staff will return to Council
soon after Council’s vacation with specific recommendations.
CMK:341:98 Page 1 of 7
This is an informational report and no Council action is required.
BACKGROUND
This report provides additional information on the Council~assignment to evaluate options
for addressing leaf blower noise, to review environmental issues, and to get community input
on potential impact associated with options. Specifically, this report includes updated
information on pending legislation, experiences of additional cities that have banned blowers,
and the process used and opinions obtained from the community. Staff anticipates
agendizing the item for discussion and action at the Policy and Services Committee meeting
of October 6. Due to the interest level on this issue, staffwill include the third staff report
in the Council packet soon after the Council returns from vacation in order to allow for
wider and timely distribution.
Other Cities’ Experience
Staff has conferred with several other cities regarding their enforcement of leaf blowers.
Contact was made with the Cities of Piedmont, Lawndale and Del Mar. The City of
Piedmont implemented a ban on fuel-powered leaf blowers in 1990. One problem it has
encountered is that gardeners use gas-powered generators for the electric blowers that are as
loud and create as many pollution problems as leaf blowers.
Del Mar adopted its ordinance banning portable, gasoline-engine blowers in 1989.
Its ordinance is enforced by code enforcement personnel and they respond to 15-25
complaints a month.
Lawndale just enacted its ordinance one year ago. They allow homeowners and gardeners
with a business license to operate electric blowers. Its code enforcement officers enforce the
ordinance and respond to about six complaints a week.
Due to the fact that over half of the cities that have banned leaf blowers are much smaller
than Palo Alto and as a result usually do not have large commercial and industrial areas,
numerous city facilities/properties or vibrant downtowns, staff has contacted some of the
larger cities to determine how they deal with the cleanliness issues in these areas without leaf
blowers.
CMR:341:98 Page 2 of 7
Since adopting its ordinance, the City of Los Angeles.has received so many complaints that
it is in the process of adopting another ordinance that would give its code enforcement
personnel enforcement authority, as significant police officer time has been spent in dealing
with the number of complaints. The City of Los Angeles has also allocated $1 million to its
Department of Water and Power to develop a battery-operated prototype leaf blower that is
quieter and as powerful as gas-powered blowers. Because City workers use brooms, many
areas of the city are not cleaned as often. Due to its concern about the cleanliness of surfaces
such as tennis, basketball, and volleyball courts, additional efforts are made to keep them
clean to ensure safety and to protect the city from increasedliability claims.
The City of West Hollywood has used general relief workers who are on unemployment and
welfare to perform some of the extra manual labor that was needed when its ordinance
became effective in 1984. The cleaning of the city’s large parking lots is contracted out and
the associated costs have increased, but actual figures were not available.
In response to the City of Menlo Park’s ban, a petition drive to put the issue to the vote of
the people was successful and it will be included on the November 1998 ballot.
The San Mateo County Board of Supervisors recently adopted a resolution that prohibits use
of any polluting garden and utility equipment by any County department or independent
contractors working for the County on "Spare the Air Days" or other days that the Bay Area
Air Quality District requests the public refrain from engaging in polluting activities.
Attachment A provides an updated list of cities that have banned leaf blowers.
Pending Legislation
Senate Bill 1651, that Senator Polanco introduced in February 1998, died in the Senate
Appropriations Committee due to the language that required the State Department of
Consumer Affairs to provide for certification of blowers. However, Senator Polanco has
amended Senate Bill 14, which originally dealt with jury service, and substituted leaf blower
language in this bill. Senate Bill 14 had already passed the Senate with its original language
and is currently pending in the Assembly. If passed, SB 14 would: prohibit cities from
establishing noise limitations on leaf blowers emitting noise levels of 65 decibels or less at
50 feet; prohibit cities from regulating leaf blowers except between 6:00 p.m. and 8:00 a.m.
on weekdays and 5:00 p.m. and 9:00 a.m. on weekends; allow cities to regulate the manner
and use of leaf blowers used to blow debris into sidewalks or gutters; require leaf blowers
used commercially after January 1, 2000 to be tested and certified by an independent testing
facility; and allow cities to adopt more stringent requirements on the hours or manner leaf
blowers may be used only through a ballot initiative approved by the majority of the voters.
Staff will continue to track this legislation.
CMR:341:98 Page 3 of 7
pollution Issues
Staff has received information regarding associated pollution issues from the California
Environmental Protection Agency Air Resources Board (CEPARB), the Environmental
Protection Agency (EPA), the Bay Area Air Quality Management District, the Sacramento
Metropolitan Air Quality Management District, and the South Coast Air Quality
Management District.
The EPA initially adopted Tier I emission standards for utility engines (engines used in lawn
and garden equipment) in 1990 that were to have became effective in 1992. However, due
to a petition filed by the utility engine industry, the implementation of the stand_ards did not
begin until 1995. Tier II standards were originally scheduled to become effective in 1999;
the implementation of those standards.has been delayed until 2000. Under the Tier II
regulations, the emissions of hand-held equipment will be reduced by about 70 percent from
the 1995 standards. Attachment B details the difference in standards between the 1995 and
2000 regulations.
Estimates developed by the CEPARB some years ago revealed that the amount of particulate
matter that is emitted from a leaf blower is equivalent to the surface dust that might be
caused by the wind blowing on a paved road or about five pounds an hour per leaf blower.
They also noted that leaf blowers are frequently used to clear paved areas such as driveways,
parking lots, etc., and thus become "dust" blowers. In a 1991 report, the CEPARB
concluded that particulate matter can cause serious health problems, especially pulmonary
and respiratory problems. The California particulate matter standard that was adopted in
1982 is 50 micrograms per cubic meter in a 24-hour period. The national 24-hour standard,
adopted in 1987 (EPA is currently revising), is 150 micrograms per cubic meter, not to be
exceeded more than once per year averaged over three years. While most particulate matter
is emitted from motor vehicles, off-road engines or engines used for lawn and garden
equipment, including leaf blowers, are responsible for a certainportion of this pollution.
However, the EPA and CEPARB do not single out leaf blowers as offenders, but include
all fuel-powered lawn and garden equipment such as mowers, chain saws, edge trimmers,
etc.
EPA documents acknowledge that hand-held equipment is primarily powered by two-stroke
engines because, unlike a four-stroke design, two-stroke engines have more operational
capability and are significantly lighter than four-stroke engines. Two-stroke engines,
however, emit higher levels of hydrocarbons, carbon monoxide, and particle matter. The
EPA has also recognized the industry’s progress towards lowering emission levels is
"significant" and is being accomplished through relatively simple engine modifications. As
a result, the CEPARB concludes that the industry is on schedule with its research and
¯ development efforts that will bring them into compliance with the Tier II standards.
CMR:341:98 Page 4 of 7
Communi _v¢ Outreach/Response
After receiving considerable information from other .cities and based upon staff research,
seven options were presented as a basis for the community outreach meetings:
A ban on all types of leaf blowers.
A ban only on fuel-powered leaf blowers.
A ban on the use of leaf blowers except in industrial parks and commercial areas.
Further restrictions on the hours of the day and days of the week they are currently
allowed.
An ordinance permitting the use of leaf blowers that are certified that they cannot be
operated at higher than 65 decibels at 50 feet and that are permitted by the City for
use in Palo Alto.
An ordinance allowing leaf blowers to be used only by private citizens on their own
property.
No changes to the current ordinance.
At each of the meetings staffhas conducted with the various interested groups, feedback on
the issues and the pros/cons of options have been obtained. Some additional ideas that were
presented at the meetings include:
The use of leaf blowers on "Spare the Air Days."
Divide the City into districts and allowing leaf blowers to be used in districts on
certain days of the week.
Conduct more educational outreach to leaf blower users on proper use.
Regulate leaf blower use based upon duration of time used (e.g., 15 minutes in an
hour).
Use mediation to settle issues between users/complainants.
Staff has met with representatives from Echo Corporation, the largest manufacturer of
commercial leaf blowers in the Country. Additionally, information from other manufacturers
has been collected. On June 10, staff held a meeting that was attended primarily by
gardeners and landscapers. Twenty-one people attended that meeting. The first general
community meeting was held on June 17. Community members were notified of this
meeting in several ways. Letters were sent to each neighborhood association and to over 70
people who had voiced opinions via letter, e-mail, telephone or oral communications at
Council meetings. A notice was included in the City’s Web page and a press release was
issued. Twenty-six people attended this meeting. Another community meeting was held on
July 15. Staff especially invited residents and business owners who hired gardeners who
used leaf blowers, as this was one segment of the community that staff had not heard from.
CMR:341:98 Page 5 of 7
Twenty people attended this meeting, seven of whom had attended one of the previous
meetings. Attachment C provides the unedited responses received at each of the meetings.
The opinions and perspectives about the use of leaf blowers and the appropriate course of
action in dealing with them are varied. Some people have ve.ry strong feelings that the o.rdy
altemative is to totally ban leaf blowers due to the noise and pollution issues. Others have
strong feelings that blowers are a necessary tool to help keep the community clean. There
is general consensus that whatever regulation/option is selected, it needs to be easy to
understand and enforce, and that the City should adhere to the same regulations as
homeowners, gardeners or businesses.
Additional Staff Work to be Completed ¯
Stuff’is finalizing the research phase of the assignment and in the process of determining cost
impacts to the City for the various options. Additionally, using all the information obtained
from the community outreach, staffwill develop recommendations for Council consideration.
In order to provide a wide and timely distribution of the staff report containing
recommendations to interested community members, staff will agendize the item for referral
to the Policy and Services Committee once the Council returns from vacation and agendize
the discussion at the Policy and Services Committee meeting on October 6.
RESOURCE IMPACTS
Staff is still in the process of estimating costs associated with the options.
ATTACHMENTS
Attachment A - Revised List of Cities Who Have Banned Leaf Blowers
Attachment B- EPA’s Hand-Held Equipment Emissions Standards
Attachment C - Unedited Responses From Community Meetings
PREPAKED BY:Lyrme Johnson, Assistant Police Chief
CMR:341:98 Page 6 of 7
REVIEWED BY:
APPROVED BY:
PO~E CHIEF
CMR:341:98 Page 7 of 7
,o o o
ATI’ACHMENT B
EPA’s HAND-HELD EQUIPMENT EMISSIONS STANDARDS
Year
1995-98
2000
Displacement.
Less than 20cc
20cc - less than 50cc
50cc and greater
All
HC
220g/bhp-hr
180
120
50
CO NOx
600g/bhp-hr
600
300
130
4.0g/bhp-hr
4.0
4.0
PM
n/a
.25
HC - Hydrocarbons
CO - Carbon Monoxide
NOx - Oxides of Nitrogen
PM - Particulate Matter
g/bhp-hr - grams per brake-horsepower-hour
Regular Meeting
Tuesday, February 23, 1999
ADJOURNMENT :
Oral Communications ...................2
Proposed 1999 Legislative Objectives ...........2
Recommendations Regarding the Regulations of the Use of Leaf
Blowers ......................... 4
Discussion for Future Meeting Schedules and Agendas 16
Meeting adjourned at I0 p.m ..........17
02/23/99 P&S: 1
Chairperson Eakins called the meeting to order at 7:10 p.m. in the
Palo Alto Art Center, 1313 Newell Road, Palo Alto, California.
Present:Eakins, Kniss, Ojakian
Absent:Schneider
i.Qr~l CQmmDnications
None
2. p~Qposed 1999 Legislative Objectives
Senior Executive Assistant Audrey Seymour said, a platform of
legislative objectives, upon which staff focused during the year,
were brought to the Policy & Services (P&S) Committee each year.
Staff refined the process to focus the platform on issues which
were important to the City, where meaningful action could be taken,
and where for~es could be joined with others sharing the same
interests. Palo Alto’s priorities were ones in which the League of
California Cities (LCC), Santa Clara County Cities Association
(SCCCA), and other groups were also interested. The staff report
(CMR:153:99) was consistent with staff’s prior practices in
bringing forward the Legislative Objectives.
Council Member Kniss asked whether staff saw any legislative
objectives germane to the City that Council Members could pursue at
the state or national level.
Council Member Kniss asked about the legislative objectives related
to revenue protection.
Ms. Seymour responded that the objectives addressed several recent
state actions; for example, the Educational Revenue Augmentation
Fund and Internet taxation, that had taken funding from local
governments, therefore jeopardizing critical City services.
Council Member Kniss said people needed to recognize how cities
constantly struggled to protect taxation dollars and how
constantly, either through mandates or Federal programs, funds were
pulled from cities that had very little power to protect the funds.
She was also sure the Internet issue would be closely watched.
Ms. Seymour replied yes. The basis of the platform came from the
LCC and included several state and national issues, such as a
social security mandate.
Council Member Ojakian said page 3 of Attachment A of the staff
report (CMR:153:99)under the Revenue and Taxation section indicated
possible revenues that might be protected.
02/23/99 P&S: 2
Ms. Seymour said Council Member Ojakian was correct. Preliminary
discussions had occurred regarding revisiting the Vehicle Licensing
Fee issue.
Council Member Ojakian asked whether the wording should be changed
from "may" to "must include the following."
Ms. Seymour said the intention of the wording was to indicate staff
would attempt to protect local revenues of any sort, listing a few
as examples of areas staff was able to identify at the current
time, but not precluding any other threat to local revenues.
Council Member Ojakian was interested in seeing some of the items
happen.
Council Member Kniss requested staff provide her with specific
information with regard to housing since she was recently asked to
participate on a national community development committee dealing
primarily with funding for housing.
Ms. Seymour said several objectives dealt with housing, such as
the Community Development Block Grant (CDBG), and others dealt with
low-income housing and tax initiatives. Staff hoped to communicate
such issues to associations to which the City belonged. Once the
platform was adopted, staff would share the information with
friends at the LCC and SCCCA and ask all Council Members to share
the platform.
Council Member Kniss appreciated Ms. Seymour’s efforts on the
legislative platform. The targeted audience did not always receive
the information.
Council Member Ojakian indicated items of particular interest to
him: I) the second item under Community Services on page 1 of
Attachment A of the staff report (CMR:153:99), "Support efforts to
fund support services such as child care and transportation for
low-income working people, tailored to fit the needs of those they
serve;" 2) the first two items under Emergency Management on the
same page, which were critical given the recent occurrences in Palo
Alto over the past year; 3) the fourth item under Public Safety on
page 3 of Attachment A, "Support legislation to allow loca!
agencies to use radar for speed enforcement on residential arterial
streets without the raising of speed limits;" and 4) the first item
under Utilities on page 3 of Attachment A, "Support local control
of decision-making for local utilities, including: rate-making;
regulatory authority; utility transfers to the general fund;
bundling of telecommunications services with electric or other
utility services; use of poles, conduits and other utilities
infrastructure; water purchases and implementation of the Best
Management Practices of the California Urban Water Conservation
Council."
02/23/99 P&S: 3
Chairperson Eakins asked about the process staff used to find
relevant pieces of legislation to support or oppose.
Ms. Seymour.said staff primarily found relevant legislation by
staying in touch with larger groups with larger staffs to track
such information. She attended meetings of the Legislative Task
Force of the SCCCA, the LCC issued bulletins~ and City staff was in
touch with a number of associations faxing alerts. She then
reviewed all of the items with the Mayor. Once the City knew about
a bill, the City could track the bill through subscription on the
Internet and obtain updates. Staff relied on such associations to
assist in finding the bills of interest to the City.
MOTION: Council Member Kniss moved, seconded by Ojakian, that the
Policy and Services Committee recommend the City Council adopt the
proposed 1999 legislative objectives as the basis for the City’s
legislative advocacy in 1999.
MOTION PASSED: 3-0, Schneider absent.
Ms. Seymour said the item would return on a future Council Consent
Calendar.
o RecommendatiQns Regarding the Regulations of the Use of Leaf
Blowers
Assistant Police Chief Lynne Johnson said staff attempted to
provide as much information in the staff report (CMR:139:99) as
possible. She said the staff recommendations in the report should
be ammended to include the prohibition of leaf blowers on Sundays
and holidays.
Chairperson Eakins clarified the additional language should be
included under Item 6 on page 2 of the staff report (CMR:139:99).
Ms. Johnson replied yes. Senator Polanco’s office confirmed he was
99.9 percent sure he would introduce legislation regarding leaf
blowers; however, his approach would differ from the one he had
taken the prior year. The details were being worked out, but she
understood the legislation would put a moratorium on any ban for
two years throughout the State and then work under State
guidelines, particularly to address the noise issue, using the
normally accepted American National Standards Institute (ANSI)
standards for noise level determinations. After Friday, the final
day for introduction of bills, more information would be
forthcoming. A great deal of interest had been raised throughout
the State and country on the leaf blower issue. Recently, she had
spoken with a representative from the Portable Power Equipment
Manufacturers Association (PPEMA), currently working on a program
with companies to affix a permanent label on leaf blowers to
indicate that the decibel level of the blower met the ANSI noise
level standard. PPEMA was currently in the process of working with
02/23/99 P&S: 4
ANSI to develop more refined and restricted testing protocol. In
a prior staff report, staff had indicated how the results of leaf
blower tests could vary depending upon certain conditions. For
example, testing a leaf blower in an enclosed room would differ
from a test in an open field. PPEMA and ANSI recognized that a
number of factors affected results and would work to make testing
more consistent.
Chairperson Eakins asked Ms. Johnson to elaborate on the process
for developing the recommendations in the report.
Ms. Johnson said staff spoke with people advocating bans on leaf
blowers, people who supported keeping the leaf blower as a too!
while mitigating the noise and pollution issues, people in
different cities throughout the state, and people from the
Environmental Protection Agency (EPA) and Air Quality Management
District (AWMD). ~Staff had tried to compile the information into
a report in such a way as to provide the Council with as much
information as possible.
Chairperson Eakins asked whether staff had held a series of public
meetings. ..
Ms. Johnson said staff had held three meetings. One was
specifically directed at landscapers and gardeners, although others
from the community attended all of the meetings. Another meeting
was targeted at residents of the community, and the last was an
attempt by staff to target the residents who hired gardeners and
landscapers who used leaf blowers.
Council Member Kniss thought staff had done an unusually good job
on the staff report (CMR:139:99). The issue was difficult. Not
everyone involved would be pleased with the decision. After having
looked at other cities and other ordinances, she asked whether
staff thought its recommendation was balanced overall.
Ms. Johnson said Council Member Kniss was accurate. Staff realized
it was in a no-win situation. Staff understood that a large group
of people were adamant about complete bans. However, some people
used leaf blowers to clean a variety of large commercial areas, not
just to blow leaves. Staff examined how City crews and contractors
cleaned. Staff had been unable to find any valid documented
information on the actua! pollution and particulate matter issues.
The ratio of one hour use of leaf blower to. the number of hours a
car was driven depended upon the source of information. The staff
needed to compile information on the community, city parks, open
spaces, and commercial areas and compare the information to other
cities that had implemented bans. Staff tried to customize the
recommendations based on its knowledge of the community.
02/23/99 P&S: 5
Council Member Kniss said the comment on page 6 of the staff report
(CMR:139:99) regarding the reduction in the sale of leaf blowers in
California was unusual.
Ms. Johnson said after having received the information, she had
heard that more leaf blowers were sold in California than any other
state and the numbers were increasing. Even. cities where bans had
been implemented had seen increases in the number of leaf blower
sales.
Council Member Kniss assumed living in a state like California was
different. She asked whether snow blowers in the east caused the
same kinds of problems. For some reason, people would not complain
about the noise of a snow blower or snow plow.
Council Member Ojakian referred to Council Member Rosenbaum’s first
point in his February 18, 1999, e-mail, "Our current ordinance
specifies db levels at 25 feet. Your proposed regulations are at
50 feet. Is there an accepted way to compare levels at the two
distances, i.e., if I know the level at 25 feet, can I predict, the
level at 50 feet? In Attachment A of CMR:139:99, the difference is
2 to 5 db. However, in Attachment B of CMR:216:98, the difference
is 3 to 13 db."
Ms. Johnson said the 50-foot distance was recognized by ANSI and
most ordinances reviewed by staff. Depending on the piece of
equipment being measured, a 5 dBA average difference occurred
between 25 and 50 feet because of various factors. Under the
City’s current ordinance, older leaf blowers could not be used at
full throttle or the noise ordinance would be exceeded. Many
times, older leaf blowers were used at half-throttle.~ Under the
proposed recommendation, the older leaf blowers could be used at
full throttle and achieve 65 dBA at 50 feet instead of 25 feet.
Council Member Rosenbaum’s second observation, "I don’t believe the
percentages on page 5 of CMR:139:99 have any relation to noise
perception (you can’t have a reduction exceeding 100%). A more
meaningful and generally accepted conclusion about relative noise
levels is given in the first paragraph of page 4 in CMR:216:98,"
was also good. A more accurate way of explaining the reduction was
understood from noise experts that for every i0 dBA reduction,
noise levels were reduced by half; for example, 65 dBA was half as
loud as 75 dBA because of the logarithmic formula used to determine
noise levels.
Traffic Division Lieutenant Don Hartnett said staff attempted to
ensure the latest technology, which produced the least amount of
noise and pollution, was used by gardeners. If nothing else, the
ordinance should be changed to reflect the fact improved technology
was available. The recommendations in the staff report
(CMR:139:99) would make the Police Department’s enforcement job
easier, would give industry targets to work for, and in some cases
an incentive for manufacturers to meet the targets in the
02/23/99 P&S: 6
ordinance. Less confusion would result if the standards in the
staff report were adhered to. Short of a ban, the recommendation
would result in the most restrictive ordinance.
Council Member Ojakian asked whether the second recommendation on
page 2 of the staff report (CMR:139:99), "permits would be issued,
for a fee, only for blowers that meet the California air quality
standards, and are rated at 65 dBA or less at 50 feet, by the
American National Standards Institute (ANSI)," was compatible with
the Comprehensive Plan.
Ms. Johnson said the Comprehensive Plan was not specific with
regard to leaf blowers. The policies indicated a desire to find
ways and strategies to reduce noise levels associated with leaf
blowers.
Chairperson Eakins asked about proactive enforcement. People who
complained about leaf blowers indicated the offender would have
left by the time a police officer arrived. She assumed the
situation would be addressed, in part, by being more proactive.
She also asked whether sworn officers or code enforcement officers
would be used.
Ms. Johnson said the enforcement effort would not completely
eliminate the scenario described by Chairperson Eakins; for
example, staff would not be able to guarantee an officer could
arrive prior to the offending party’s departure. Proactive
enforcement involved not waiting until complaints were received.
Normal controls would be on the lookout for someone using a leaf
blower to ensure a permit was being carried. With the permit
concept, it would be easy to determine whether or not the leaf
blower was in violation. Officers would continue to respond to
complaints, but no guarantees could be made about response times or
finding a violator in action. The permit concept would make
enforcement easier when an officer arrived on the scene and found
someone who was using a leaf blower.The Community Service
Officers (CSO) would handle enforcement.If the Council approved
the recommendation, staff would request temporary funding for
another CSO to provide the needed coverage. Action would be taken
when a patrol officer witnessed leaf blowers.
Chairperson Eakins asked whether someone like her neighbor, who
owned his own equipment, would be affected.
Ms. Johnson said staff had recommended applying the prohibition to
everyone, including homeowners. An officer who saw someone using
a leaf blower on a Sunday would have a difficult time determining
whether or not the person actually lived at the residence. It.
could be done, but was more difficult with regard to enforcement.
David Schrom, 381 Oxford Avenue, spoke in opposition to leaf
blowers due to the impact on global environmental pollution. The
02/23/99 P&S: 7
economic analysis in the staff report (CMR:139:99) was shallow,
since the number of people affected by the noise of leaf b!owers
resulted in such a high cost to the community. A more honest
estimate of the cost of leaf blowers might result in a very
different answer.
Ellen Fletcher, 777 San Antonio Road #108, said one comment on pa~e
Ii of the staff report (CMR:139:99), "leaf blowers...do produce
noise levels that are offensive and bothersome to some
individuals," was highly understated. On the same page, the
comment was made that "while there are other types of tools that
can be used, the majority of them require at least 30 to 50 percent
more time to complete the work compared to leaf blowers..."
However, in her apartment complex when rakes were used, the workers
were very fast and efficient. Leaf blowers usually blew leaves
into the street which was illegal and created a hazard for
bicyclists. Police officers rarely cruised neighborhoods, where
most of the leaf blowers were used. She asked how a homeowner
could handle a neighbor’s noisy leaf blower.
Council Member Kniss said Ms. Fletcher was on the City Council when
the issue of leaf blowers was addressed and asked why the
recommendation had been so resound±ngly defeated in 1987.
Ms. Fletcher said the proposed recommendation meant that for the
first time noise and time limits would exist for leaf blower use.
Older homeowners opposed a ban on leaf blowers because their
gardeners threatened not to work without the use of leaf blowers.
Leaf blower manufacturers had also made a case about the noise
level reductions that would appear with newer models. She and
former Council Member Patitucci had fought for the ban.
Kathleen Haney, Cardinal Hotel, 235 Hamilton Avenue, spoke in
support of the staff recommendation, but preferred an outright ban
on leaf blowers. Leaf blower noises in the Downtown area in the
late evening bounced off of buildings, unlike residential areas
where trees and grass softened the noise levels. The P&S Committee
was asked to consider the noise levels Downtown and include
restrictions in the hotel zone during the evenings.
Lorilee Houston, Garden Court Hotel, 520 Cowper Street, agreed with
Ms. Haney about the need for restrictions on leaf blowers in hotel
zones in the evenings and early mornings.
Council Member Kniss asked about the parameters for a hotel zone.
Ms. Haney said the hotel owners were willing to work with staff on
the parameters.
Terry Burnes, 183 Ferne Avenue, spoke in favor of the staff
recommendation, but asked that the location of violations from the
past year be plotted out on a map. Some areas were worse than
02/23/99 P&S: 8
others. Leaf blowers were not a problem in his neighborhooH, even
though the noise from leaf blowers might bother someone
occasionally. He queried how a private individua! would know
whether or not a leaf blower purchased in Palo Alto was going to be
legal. The materials were unclear about whether leaf blowers would
be certified based on a rating affixed by the manufacturer or
tested by the City. Staff was encouraged to focus on a standard of
pre-established ratings so individuals would know at the time of
purchase whether a blower would be lega! or not. Under the
proposal, individuals like himself who worked full time and cleaned
their own yards would only be able to clean yards on Saturdays. He
requested extended evening hours or Sunday hours from ii a.m. to 3
p.m., particularly during the summer, to allow use of leaf blowers
after work. Having police officers stop in neighborhoods to check
leaf blowers for compliance seemed "heavy handed." He urged
handling of the issue differently, particularly with regard to
residents. He appreciated the attempt to reach a compromise.
Yasuo Shinozuka, 894 Cabot Lane, Foster City, spoke in favor of the
staff recommendation with minor changes. The revoking of a license
as a penalty seemed strict. Gardeners being penalized the same way
for not using an extension tube as for exceeding 65 dBA was unfair.
More flexible hours to provide laborers with more time to work was
encouraged; for example, 8:30 a.m. to 5:30 p.m. or even 8 a.m. to
6 p.m. Small business gardeners were often unable to complete work
in the time allotted.
Chairperson Eakins asked what Mr. Shinozuka meant by his comment
regarding extension tubes.
Mr. Shinozuka referred to item 4 on page 2 of the staff report
(CMR:139:99), "leaf blowers must be operated with all extension
tubes in place."
Chairperson Eakins asked why gardeners would not want to use the
tubes.
Mr. Shinozuka said vendors sold the extension tubes longer than
gardeners might want them. The longer tubes were for under shrubs,
similar to an extension for a vacuum cleaner.
Chairperson Eakins asked whether the ordinance should allow for
shorter tubes.
Mr. Shinozuka replied no. The long tube was fine, but someone with
a short tube might be caught by a police officer and have their
license revoked.
Mr. Burnes thought Mr. Shinozuke was trying to say that putting
someone with-two violations out of business was unfair when the
violation might be as simple as merely using the wrong extension
02/23/99 P&S: 9
tube. He thought Mr. Shinozuka was saying a citation should not be
written for using the wrong combination of tubes.
Chairperson Eakins asked whether that was Mr. Shinozuka’s point.
Mr. Shinozuka replied yes.
Chairperson Eakins asked staff to respond to the questions raised
by members of the public at the end of the meeting.
John K. Abraham, 736 Ellsworth Place, spoke in favor of a total ban
on leaf blowers. However, support was given to staff’s enforcement
plan if the ban was not possible. The 65 dBA ANSI standard had
been supported by the environmental coalition. Support was given
to the prohibition of leaf blowers on holidays. The P&S Committee
was encouraged to provide the Police Department with all the
assistance necessary to carry out the ordinance via the CSOs. The
comment on Attachment D of the staff report (CMR:139:99) indicating
the total cost of using leaf blowers in parking lots of
approximately $37,000 would double under a complete ban was in
error. Prior speakers’ recommendations to disallowing leaf blowers
until at least 7 a.m. in parking lots was encouraged, particularly
near hotels. A revisitation of the:issue in a year was supported.
Frank Manocchio, 2115 White Oak Way, San Carlos, spoke on behalf of
the California Landscape Contractors Association (CLCA), and
thanked the City for the professionalism and objectivity of the
staff report (CMR:139:99). The CLCA represented a variety of
contractors. In general, the staff recommendation was supported.
Some CLCA members might consider the hours or days a little
restrictive, but the CLCA thought it should be part of the solution
and not part of the problem. As one of the technology centers of
the world, Palo Alto should recognize the benefits of technology.
Small engine motors would be dramatically less polluting and
quieter in the following years.
Henri Ocafrain, 1860 Palm Avenue, Redwood City, had worked in Palo
Alto for 30 years using leaf blowers. The Bay Area Gardeners
Associatien (BAGA), of which he was a member, tried to cooperate
with the desire of Bay Area cities to reduce noise and pollution
levels resulting from the use of leaf blowers. The City was asked
to change the hours of use to 8 a.m. instead of 9 a.m. to 5 p.m.
Kathy Strephmouis, 6 Delmar Court, Redwood City, spoke as a small
gardening business operator who worked in residential areas and
used the gardening tools minimally and quietly. Her business
recently purchased a 62 dBA leaf blower for $450, a high price for
a small business owner. Snow blowers had only two-cycle engines
rather than the four-cycle engines used in leaf blowers. The staff
report (CMR:139:99) provided very good reasoning, leaving gardeners
to do their job without being disturbed. Gardeners were willing to
cooperate with the rules.
02/23/99 P&S:I0
Rafael G. Madriz, 342 Beverly Avenue, Millbrae, spoke as a member
of BAGA which was. trying hard to use the best tools possible.
People unhappy about leaf blowers should contact the manufacturers
of the tools to ensure the best equipment was being produced to
meet community requirements. The staff report (CMR:139:99) was
appropriate, except for the hours of operation and the permit
requirements because of the expenses.
Valentin Gonzalez, 312 Semicircular Road, Menlo Park, spoke in
favor of the leaf blower recommendations but opposed the
restriction on hour~ of operation. Another concern was whether, in
two years, leaf blowers would be manufactured to meet the more
stringent regulations. The hours of 8 a.m. to 5 p.m. were
suggested.
Robin Pendergrast, Echo, Inc., Lake Zurich, Illinois, spoke as a
representative of~a major manufacturer of leaf blowers. Staff was
complimented on the complete and professional report (CMR:139:99).
In 1987, the average leaf blower emitted 78 dBA, which had since
been reduced to the 65 dBA level. Progress was made from a
technical standpoint. Courtesy was an issue that had not been
addressed. In dealing with cities across the country, it was
obvious the problem centered on a~few individuals who would not
respect their neighbors, communities, or employers. Echo, Inc-.
produced a good number of leaf b!owers. Even if manufacturers
created blowers which were quieter, the blower had to be used with
the tubes attached and in the appropriate settings.
Chairperson Eakins asked how soon four-cycle engines would be
available in leaf blowers.
Mr. Prendergast said the four-cycle engine was far from being
perfected. The tier-two carburetor standards, which would come
into effect on January i, 2000, detailed specific emission
requirements which would be met by two-cycle engines. From Echo’s
perspective, the four-cycle engine was not in the planning stages.
Quieter, battery-operated blowers were possibilities. However, the
four-cycle engine involved many design and carburetion issues
making it very difficult to design to leaf blower applications.
Chairperson Eakins asked about certification. Mr. Burnes had spoke
of pre-certifying units so the City would not have to go through a
permitting process.
Mr. Prendergast said a self-labeling standard was currently being
structured, which meant a very specific legal parameter would be
used. The same type of approach was used in positioning engines to
meet carburetor standards for the year 2000, with specific
Environmental Protection Agency (EPA) standards as far as the
testing process. A check system was in place to make sure all
manufacturers met the standards. The same was true for self-
labeling standards. Home Depot, Orchard Supply, or any dealership
02/23/99 P&S:II
provided a dBA rating based upon a specific ANSI standard. PPEMA
represented the major manufacturers and recognized the importance
of maintaining the integrity of the testing and labeling standard.
Council Member Ojakian asked for clarification of the statement
about dBA level changes from 78 dBA in 1987 to the current level of
65 dBA.
Mr. Prendergast said currently, one manufacturer produced a
backpack leaf blower lower than 65 dBA. The 62 dBA level mentioned
in the staff report (CMR:139:99) was being challenged because it
had not actually been tested to the ANSI standard. Some challenges
were being waged against a few small manufacturers.
Council Member Ojakian asked where the process was headed.
Mr. Prendergast said to go from 78 dBA to 65 dBA in 12 years was an
accomplishment and a move down to 62 dBA might be possible within
a few years. The 65 dBA blower was substantially~quieter than
other pieces of lawn and garden equipment.
Council Member Ojakian asked whether the third recommendation on
page 2 of the staff report (CMR:139:99), "in two years, permits
would be issued only for blowers that meet the California air
quality standards, ~and are rated at 62 dBA or less at 50 feet, by
the ANSI standards," was reasonable to expect.
Mr. Prendergast said he could not guarantee that leaf blower levels
would be down to 62 dBA in two years; however, manufacturers were
often able to do amazing things when challenged to do so.
Gerardo Lombera, 438 Stamford Avenue, Redwood City, member of BAGA,
said gardeners understood the noise problem and were working hard
to regulate the noise. BAGA was holding seminars to educate
gardeners about and chemicals. BAGA was willing to work with all
of the cities to prevent the problems and invited the City to
attend a BAGA meeting to work together for a solution.
Council Member Kniss asked that a BAGA member provide the City with
more information about the organization and extend an invitation to
a meeting.
Terry Trumbull, American Lung Association, I011 Lincoln Avenue,
spoke in support of the staff recommendation. The staff report
(CMR:139:99) had appropriately pointed to several major air quality
problems. Ozone standards had been violated in the Bay Area since
1980, and combustion system in leaf blowers was the primary source
of the ozone problem. The second.problem was the massive dust
generated from the blowing capacity, since the dominant source of
problems violating Federal and State standards was dust. The City
was encouraged to work with the gardeners and to adopt standards,
related to available technology. The two-cycle engine, was likely
02/23/99 P&S:12
to be banned within the next two years because of air quality
standards. Moving to electrical units within one or two years was
also encouraged. Electrical plug usage was limited to a specific
range, so an exception for larger distances could be accommodated
to allow gas-based tools.
Chairperson Eakins asked Mr. Trumbull to provide City staff with
materials on establishing and implementing technology improvement
standards.
Mr. Trumbull agreed.
Ramon Quezada, President BAGA, 445 Lancaster Way, Redwood City,
congratulated the staff for demonstrating democracy. The BAGA was
involved in training its people. The staff report (CMR:139:99) was
good, but more clarification about permits was requested. Most
BAGA members already had leaf blowers, so to purchase a new blower
as well as pay a permit fee seemed unreasonable. The two-year
limit of 62 dBA was also difficult, since the purchase of a 65dBA,
with a lifetime of 3 to 5 years, resulted in an ultimate loss for
individuals with very small incomes. The BAGA was willing to hold
a meeting in Palo Alto’s City Hall.
Chairperson Eakins thought staff would be very interested in
working with BAGA.
Mr. Quezada said BAGA was interested in working with the City..
Once the organization understood the problems, efforts were made to
alleviate the problems. Palo Alto’s actions were applauded.
Police staff were very helpfu! and should be commended.
Franscisco Quezadaz, 208 4th Avenue, Redwood City, member of BAGA,
said the BAGA membership was primarily represented by small
businesses with one or two helpers. Purchasing licenses, permits,
and related fees from various cities was a burden tO small
companies. The requirement for a 62 dBA leaf blower within two
years was an additional expense. Certifying every individual who
operated leaf blowers would also be an expense to a small company.
BAGA tried to train itself, ensuring helpers were also trained, and
do as much as possible to comply with the requirements, while
keeping costs to a minimum.
Recess: 9:10 9:2~ p.m.
Miguel Sanchez, 240 Mt. Home Road, Woodside, Member of BAGA, spoke
regarding the desire of the BAGA to work with the City. The issue
of purchasing leaf blowers every two years was very difficult for
gardeners. Manufacturers were trying to reduce noise levels, but
the rule was analogous to requiring individuals to purchase a new
car every two years. The gardeners worked hard to satisfy
customers and beautify the City.
02/23/99 P&S:I3
Anne C. Fletcher, 2020 Waverley Street, spoke in support of leaf
blowers. People who complained about leaf blowers could purchase
ear plugs for the 15 minutes it took to clear a yard as a sign of
cooperation between neighbors. Mildew and mold resulting from
leaves sitting for several weeks created allergy problems.
Gardeners should not have to pay for permits. Raking was
unsatisfactory for yards such as hers which had large flower beds
and ivy.
Chairperson Eakins wanted the P&S Committee to discuss the issue
and to make a field excursion to observe a demonstration of leaf
blowers in action.
Council Member Kniss presented a list of questions staff could
address within the confines of the issue: i) the ~grandfathering"
issue with regard to homeowners purchasing leaf blowers and the
appropriate restrictions; 2) the hours with regard to gardeners and
full-time workers who cared for their own gardens; 3) exact
language regarding extension tubes and other tools, perhaps
explained within the demonstration; 4) proactivity, i.e., whether
residents would feel threatened with arrest because of using their
own blower during a prohibited time; 5) hotel hours, including
holidays and Sundays; 6) tags on machines; 7) certification and
training; 8) working with BAGA and how the City could be more
interactive and supportive; 9) whether or not to charge for the
permits; I0) education and seminars; and ii) the different types of
machines. The questions could be answered at the next P&S
Committee.
Council Member Ojakian presented a list of questions: I) why the
number of violations resulting in a revoked permit had been set at
two; 2) whether after permitting a machine at 65 dBa according to
the second recommendation, recommendation three also had to be
followed; 3) how to determine noise levels of machines; for
instance, manufacture’s certified information or the City’s own
testing, and how it would be performed; 4) how the information
would be reported back to the Council; such as, measuring
complaints or using a matrix of the information gathered; 5) why
had complaints increased percent per year; and 6) why not require
mufflers as legislation in other cities had. The use of equipment
anywhere near residences at 4 a.m. was unreasonable. A more
rational time to start was 6 or 7 a.m. Staff’s approach to find
common ground to satisfy most people was appreciated. The report
was thorough and objective and data provided on other city’s
ordinances was helpfu!.
Council Member Kniss commended staff’s extensive work and research.
Much of-the issue was dependent on compromise. Staff had made an
excellent start.
Chairperson Eakins thanked staff for the organized and complete
report that was easy to read, with good information and background.
02/23/99 P&S:I4
The speakers were thanked for their courtesy in their
presentations. Regarding the question of noise, other noise
situations existed; such as, tennis courts, Downtown music, and
sound walls. People had different reactions to various types of
noises. Someone might not be willing to live near a train but had
no problem with leaf blowers. Some sounds were considered hostile
and some comforting. She appreciated the spirit of compromise and
accommodation. A solution should be found which allowed everyone
involved to maintain respect. The education BAGA provided was
appreciated. Perhaps homeowners and gardeners not in the
organization could participate in the training for certification or
accreditation, which would work better than a permit system which
required so much administration. Some leaf blowers "chased every
crumb," as Ellen Fletcher stated, and pushed debris into bicycle
lanes. Although not all gardeners participated in such a practice,
some tools were able to perform a very efficient job. The self-
labeling standard-might be pursued with manufacturers and industry
groups, to develop a standard the City could accept and depend
upon, and residents would be comfortable with. Staff was asked to
elaborate and explain some of Mr. Trumbull’s comments on technology
and standards.
Ms. Johnson said a demonstration could easily arranged and asked
whether the P&S Committee wanted the demonstration organized in a
meeting setting.
Chairperson Eakins suggested providing the demonstration for the
entire Council.
Ms. Johnson assumed staff would bring in various models of leaf
blowers to the demonstration that were rated at different dBA
levels to assist in determining differences.
Chairperson Eakins was interested in seeing the different fuel
options, including electric.
Council Member Ojakian said the distance factor was also important.
Chairperson Eakins was interested in seeing a demonstration of the
green machine.
Ms. Johnson asked whether the P&S Committee was interested in any
other types of gardening tools or just leaf blowers and the green
machine.
Chairperson Eakins said leaf blowers and the green machine were
sufficient.
Council Member Ojakian was also interested in seeing an electric
leaf blower for comparison.
02/23/99 P&S:I5
Ms. Johnson asked when the P&S Committee was interested in seeing
the demonstration.
Chairperson Eakins suggested April. Ms. Seymour would need to
provide assistance with scheduling. The City might have a trial
plot where non-gasoline powered tools were used and might look into
demonstration of landscaping. The Bay Area Quality Board (BAAQB),
which had encouraged the~City to consider wood smoke, would also
look into a horticultural tool ordinance.
Council Member Kniss presumed no changes would be made to the
current ordinance until the item returned to the P&S Committee and
the Council.
Ms. Seymour said the item would remain in committee until the P&S
Committee was prepared to make a recommendation to the Council and
the Council appro~ved the recommendation.
Council Member Kniss clarified nothing was altered, so the public
could be assured of the conditions of the current ordinance, until
the Council passed a new ordinance.
Ms. Johnson said the Council had given staff direction in the past
to develop a permit fee that was cost-recovery. She asked whether
that was an issue for leaf blower permits.
Council Member Kniss said the P&S Committee had not been given
sufficient information on which to make such a decision, which she
hoped would become evident after staff addressed the questions
posed that evening. Prior to the current meeting, she had not
realized gardeners needed permits in every community in which they
worked. The financial impact to gardeners should be examined.
Council Member Ojakian said it was difficult to answer the question
since the program might have additional costs. The cost recovery
issue might involve penalties, so to determine how people would be
permitted, the dollars received for the permits plus the citations,
would be necessary.
MOTION: Council Member Ojakian moved, seconded by Kniss, to
continue the issue regarding the regulations of the use of leaf
blowers in Palo Alto to a date uncertain.
MOTION PASSED: 3-0, Schneider absent.
4. DiscussiQn..for Future Meeting Schedul@s and Agendas
Senior Executive Assistant Audrey Seymour said the next P&S
Committee meeting was scheduled for March 9, 1999. Council Members
Eakins and Schneider would be absent, so an alternate would be
necessary for a quorum. The topics would include overnight parking
and flood hazard regulations. Topics for the April 13, 1999 P&S
02/23/99 P&S:I6
Committee meeting would be median/driveway solicitation and a stop
sign intersection update.
ADJOURNMENT: Meeting adjourned at I0 p.m.
NOTE: Sense minutes (synopsis) are prepared in accordance w~th
Palo Alto Municipal Code Sections 2.04.180(a) and (b). The City
Council and Standing Committee meeting tapes are made solely for
the purpose of facilitating the preparation of the minutes of the
meetings. City Council and Standing Committee meeting tapes are
recycled 90 days from the date of the meeting. The tapes are
available for members of the public to listen to during regular
office hours.
02/23/99 P&S:I7
POTENTIAL HEALTH AND ENVIRONMENTAL
IMPACTS
OF LEAF BLOWERS
Report to the California Legislature
CALIFORNIA AIR RESOURCES BOARD
OCTOBER 29, 1999
DRAFT FOR COMMENT ONLY
DO NOT CITE OR QUOTE
1.0 EXECUTIVE SUMMARY
Introduction
Senator John Burton introduced California Senate Concurrent Resolution No. 19
(SCR 19) February 23, 1999, which was chaptered May 21, 1999. The resolution requests
the Air Resources Board (ARB) to prepare and submit a report to the Legislature on or
before January 1, 2000, "summarizing the potential health and environmental impacts of
leaf blowers and including recommendations for akernatives to the use of leaf’blowers
and alternative leaf blower technology if the state board determines that alternatives are
necessary." The goal of this report is to summarize for the California Legislature existing
data on health and environmental impacts of leaf blowers, to identify relevant questions
not answered in the literature, and suggest areas for future research.
As per SCR 19, this report includes a comprehensive review of existing studies of
the impacts of leaf blowers on leaf blower operators and on the public at large, and of the
availability and actual use of protective equipment for leaf blowers. The receptors
identified by the resolution are humans and the environment; sources of impacts are
exhaust, noise, and dust. Because the Legislature specified that ARB use existing
information, staff conducted no new studies. In order to locate existing data, staff
searched the published literature, contacted potential resources and experts, and requested
data from the public via U.S. mail and through a web page devoted to the leaf blower
report.
The methodology followed for this report depends on both the objectives of SCR
19 and available data. As staff discovered, in some areas, such as exhaust emissions,
much is known; in other areas, such as fugitive dust emissions, we know very little. For
both fugitive dust and noise, there are few or no data specifically on leaf blower impacts.
For all hazards, there have been no dose-response studies related to emissions from leaf
blowers and we do not know how many people are affected by those emissions.
Therefore, staff determined to provide the Legislature with a report that has elements of
both impact and risk assessments.
The body of the report comprises three components: hazard identification, review
of health effects, and a characterization of the potential impacts of leaf blowers on
operators and bystanders. In Chapter 3, the emissions are quantified as to specific
hazardous constituents, the number of people potentially exposedto emissions is
discussed, and laws that seek to control emissions are summarized. Chapter 4 reviews
health effects, identifying potential negative health outcomes of exposure to the identified
hazards. Chapter 5 is a synthesis of hazard identification and health effects,
characterizing potential health impacts that may be experienced by those exposed to the
exhaust emissions, fugitive dust, and noise from leaf blowers in both occupational and
non-occupational setting. In addition, Chapter 6 comprises a discussion of research needs
to make pro~ess toward answering some of the questions raised by this report, and
Chapter 7 briefly describes engine technologies that could reduce exhaust emissions, and
discusses methanol fuel and alternatives to leaf blowers.
The leaf blower was invented by Japanese engineers in the early 1970s and
introduced to the United States as a lawn and garden maintenance tool. Drought
conditions in California facilitated acceptance of the leaf blower as the use of water for
many garden clean-up tasks was prohibited. By 1990, annual sales were over 800,000
nationwide, and the tool had become a ubiquitous gardening implement. In 1998,
industry shipments of gasoline-powered handheld and backpack leaf blowers increased
30% over 1997 shipments, to 1,868,160 units nationwide.
Soon after the leaf blower was introduced into the U.S., its use was banned as a
noise nuisance in two California cities, Carmel-by-the-Sea in 1975 and Beverly Hills in
1978. By 1990, the number of California cities that had banned the use of leaf blowers
was up to five. There are currently twenty California cities that have banned leaf blowers,
sometimes only within residential neighborhoods and usually targeting gasoline-powered
equipment. Another 80 cities have ordinances on the books restricting either usage or
noise level or both. Nationwide, two states, Arizona and New Jersey, have considered
laws at the state level, and five other states have at least one city with a leaf blower
ordinance.
The issues usually mentioned by those who object to leaf blowers are health
impacts from noise, air pollution, and dust. Municipalities regulate leaf blowers most
often as public nuisances in response to citizen complaints. Two reports were located that
address environmental concerns: the Orange County Grand Jury Report, and a series of
reports from the City of Palo Alto City Manager’s office. The City of Palo Alto reports
were produced in order to make recommendations to the City Council on amending their
existing ordinance. The Orange County Grand Jury took action to make
recommendations that would "improve the quality of life in Orange County," and
recommended that cities, school districts, community college districts, and the County
stop using gasoline-powered leaf blowers in their maintenance and clean-up operations.
The major findings of each are similar: leaf blowers produce exhaust emissions,
resuspend dust, and generate high noise levels (Table 1). The implications of these
findings for human health, however, were not documented or based on scientific studies.
Description ot~ the Hazards
Hazard identification is the first step in an impact or risk assessment. Each of the
three identified hazards are examined in turn, exhaust emissions, dust emissions, and
noise. For each, the hazard is described and quantified, and the number of people
potentially exposed to the hazard is discussed. For exhaust emissions the number of
people potentially impacted is as high as the population of the state, differing within air
basins. Fugitive dust emissions impact a varying number of people, depending on one’s
proximity to the source, the size of the particles, and the amount of time since the source
resuspended the particles. Finally, we also discuss laws that control the particular hazard.
Exhaust emissions from leaf blowers consist of the following specific pollutants
of concern: hydrocarbons from both burned and unburned fuel, and which combine with
other gases in the atmosphere to form ozone; carbon monoxide; fine particulate matter;
and other toxic air contaminants in the unburned fuel, including benzene, 1,3-butadiene,
acetaldehyde, and formaldehyde. Exhaust emissions from these engines, while high
compared to on-road mobile sources on a per engine basis, are a small part of the overall
emission inventory. Emissions have only been controlled since 1995, with more stringent
standards takin~ effect in 2000. The exhaust emissions from leaf blowers are consistent
with the exhaust emissions of other, similar off-road equipment, such as string trimmers.
Manufacturers have developed several different methods to comply with the standards
and have done an acceptable job certifying and producing engines that are below the
regulated limits.
Dust emissions from leaf blowers are not part of the inventory of fugitive dust
sources. ARB, therefore, does not have official data on the quantity of fugitive dust
resuspended by leaf blowers. To what extent leaf blowers are efficient mechanisms for
entraining total suspended particulates and smaller particles in ambient air needs to be
measured, using leaf blowers to clean selected surfaces that are representative of actual
leaf blower usage. Available data indicate that the PM10 emissions impact from fugitive
dust suspended by leaf blowers is small, but probably not insignificant. Previous emission
estimates range from less than 1% to 5% of the statewide PM10 inventory. For example,
the ARB previously estimated statewide fugitive dust emissions to be about 5 percent of
the total, and the Sacramento Metropolitan AQMD estimated leaf blower fugitive dust
emissions to be about 2 percent of the Sacramento county PM10 air burden. A more
definitive estimate of leaf blower fugitive dust emissions will require research to verify
appropriate calculation parameters, determine representative silt loadings, measure actual
fugitive dust emissions through source testing, and identify the chemical composition of
leaf blower-generated fugitive dust.
Noise is the general term for any loud, unmusical, disagreeable, or unwanted
sound, which has the potential of causing hearing loss and other adverse health impacts.
While millions of Californians are likely exposed to noise from leaf blowers as
bystanders, given the ubiquity of their use and the increasing density of California cities
and towns, there is presently no way of knowing for certain how many are actually
exposed, because of the lack of studies. In contrast, it is likely that at least 60,000 lawrt
and garden workers are daily exposed to the noise from leaf blowers. Many gardeners
and landscapers in southern California are aware that noise is an issue and apparently
would prefer quieter leaf blowers. Purchases of quieter leaf blowers, based on
manufacturer data, are increasing. While little data exist on the noise dose received on an
8-hr time-weighted-average by operators of leaf blowers, data indicate that some
operators may be exposed above the OSHA permissible exposure limit. It is unlikely that
more than 10% of leaf blower operators and members of the gardening crew, and
probably a much lower percentage, regularly wear hearing, eye, or breathing protective
gear, thus exposing them to an increased risk of hearing loss. The sound quality of
gasoline-powered leaf blowers may account for the level of annoyance reported by
bystanders.
Review of Health Effects
Potential health effects of the hazards range from mild to serious. Airborne PM is
not a single pollutant, but rather is a mixture of many subclasses of pollutants, each
containing many different chemical species. Many epidemiological studies have shown
statistically significant associations of ambient PM levels with a variety of negative
health endpoints, including mortality, hospital admissions, respiratory symptoms and
illness, and changes in lung function. Carbon monoxide exposure causes health effects
ranging from subtle changes to death. At low exposures, CO causes headaches, dizziness,
weakness, and nausea. Children and people with heart disease are particularly at risk
from CO exposure. Some toxic compounds in gasoline, in particular benzene, 1,3-
butadiene, acetaldehyde, and formaldehyde, are carcinogens. Ozone, formed from
chemical reactions of hydrocarbons and nitrogen dioxide in the presence of sunlight, is a
strong irritant and exposures can cause airway constriction, coughing, sore throat, and
shortness of breath. Finally, noise exposures damage hearing, and causes other adverse
health impacts, including interference with communication, rest and sleep disturbance,
changes in performance and behavior, annoyance, and other psychological and
physiological changes that may lead to poor heakh.
Potential Health Impacts of Leaf Blowers
Health effects from hazards identified as being generated by leaf blowers range
from mild to serious, but the appearance of those effects depends on exposures: the dose,
or how much of the hazard is received by a person, and the exposure time. Without
reasonable estimates of exposures, ARB cannot conclusively determine the health
impacts from leaf blowers; the discussion herein clearly is about potential health impacts.
The goal is to direct the discussion and raise questions about the nature of potential health
impacts for those exposed to the exhaust emissions, fugitive dust, and noise from leaf
blowers in both occupational and non-occupational settings.
For the worker, the analysis suggests concern. Bearing in mind that the worker
population is most likely young and healthy, and that these workers may not work in this
business for all of their working lives, we nonetheless are cautioned by our research. Leaf
blower operators may be exposed to potentially hazardous concentrations of CO and PM
intermittently throughout their workday, and noise exposures may be high enough that
operators are at increase risk of developing hearing loss. While exposures to CO, PM,
and noise may not have immediate, acute effects, the potential health impacts are greater
for long term exposures leading to chronic effects.
Noise and PM effects should be protected against by the use of respirators and
earplugs or muffs. Employers should be more vigilant in requiring and ensuring their
employees wear hearing protection. Regulatory agencies should conduct educational and
enforcement campaigns, in addition to exploring the extent of the use of protective gear.
Exposures to CO are more problematic; there are no CO filters, but engine modification
can reduce CO exhaust emissions. More study of CO exposures to leaf blower operators
is warranted to determine whether the potential health effects discussed herein are actual
effects or not.
Describing the impacts on the public at large is more difficult than for workers
because people’s exposures and reactions to those exposures are much more variable.
Bystanders are clearly annoyed by the noise and dust from leaf blowers. They can be
interrupted, awakened, and may feel harassed, to the point of taking the time to contact
public officials, complain, write letters and set Up web sites, form associations, and attend
city council meetings. These are actions taken by highly annoyed individuals who believe
their health is being negatively impacted. In addition, some sensitive individuals may
experience extreme physical reactions, mostly respiratory symptoms, from exposure to
the kicked up dust.
On the other hand, others voluntarily purchase and use leaf blowers in their own
homes, seemingly immune to the effects that cause other people such problems. While
these owner-operators are likely not concerned about the noise and dust, they should still
wear protective equipment - dust masks and ear plugs - and their exposures to CO are a
potential problem and warrant more study.
Recommendations
The Legislature asked ARB to include recommendations for alternatives in the
report, if ARB determines alternatives are necessary. This report makes no
recommendations for alternatives. Based on the lack of available data, such conclusions
are premature at this time. Of course, ARB can certainly recommend reducing exhaust
emissions from the engines, particularly of carbon monoxide and unburned fuel. For
noise, the ARB has no Legislative mandate to control noise emissions, but the evidence
seems clear that quieter leaf blowers would reduce worker exposures and protect hearing,
and reduce negative impacts on bystanders. Research is needed to better understand the
issues relating to ttie health and environmental issues from leaf blowers. Research needs
are discussed throughout the report and again in Appendix H.
Fugitive dust emissions are more problematic. The leaf blower is designed to
move relatively large materials, which requires enough force to also blow up dust
particles. Banning or restricting the use of leaf blowers could reduce fugitive dust
emissions, but there are no data on fugitive dust emissions from alternatives, such as
vacuums, brooms, and rakes. In addition, without a more complete analysis of potential
health impacts, costs and benefits of leaf blower use, and potential health impacts of
alternatives, such a recommendation is not warranted. Some have suggested that part of
the problem lies in how leaf blower operators use the tool, that leaf blower operators need
to show more courtesy to passersby, shutting off the blower when people are waking by,
and that too many leaf blower operators blow dust and debris into streets, leaving the
materials to be resuspended by passing vehicles. A more complete understanding of the
amount of dust resuspended by leaf blower use and alternative cleaning equipment is
needed to guide decision-making, but in the meantime, interested stakeholders could join
together to propose methods for leaf blower use that might reduce dust generation, and
develop and promote codes of conduct by workers who operate leaf blowers.
POTENTIAL HEALTH AND ENVIRONMENTAL IMPACTS
OF LEAF BLOWERS
SEPTEMBER 15, 1999
CALIFORNIA AIR RESOURCES BOARD
PREPARED FOR THE CALIFORNIA LEGISLATURE
DRAFT FOR COMMENT ONLY
DO NOT CITE OR QUOTE
PLEASE SUBMIT COMMENTS TO
DR. NANCY STEELE,
AIR RESOURCE BOARD,
9480 TELSTAR AVENUE, SUITE 4,
EL MONTE, CA 91731-2990
NO LATER THAN OCTOBER 8, 1999.
Table of Contents
1.0
2.0
3.0
Executive Summary (not available in this draft)
Introduction
2.1 Senate Concurrent Resolution 19 - Leaf Blowers
2.2 Health and Environmental Impacts
2.3 Timeline
2.4 15abli~ .Outreach
2.5 History of the Leaf Blower and Local Ordinances
2.6 Overview of This Report
Description of the Hazard
3.1 Exhaust Emissions
3.1.1 Characterization of Technology
3. t.2 Exhaust Emissions
3.1.2.1 Leaf Blower Population
3.1.2.2 Emission Inventory
3.1.3 Regulating Exhaust Emissions
3.1.3.1 State Regulations
3.1.3.2 U.S. EPA Regulations
3.1.3.3 SCAQMD Emissions Credit Program
3.1.4 Summary
3.2 Fugitive Dust Emissions
3.2.1 Definition of Fugitive Dust Emissions
3.2.2 Calculating Leaf Blower Emissions
3.2.2.1 Generation of Fugitive Dust by Leaf Blowers
3.2.2.2 Size Segregation of Particulate Matter
3.2.2.3 Calculation Assumptions
3.2.2.4 Calculation Methodology
3.2.3 Characterization of Fugitive Dust Emissions
3.2.3.1 Previous Emissions Estimates: ARB, 1991
3.2.3.2 Previous Emissions Estimates: SMAQMD
3.2.3.3 Emission Factors - This Study
3.2.3.4 Emissions Inventory - This Study
3.2.4 Chemical Composition
3.2.5 Regulating Fugitive Dust Emissions
3.2.5.1 State and Federal PM10 and PM2~5 Standards
3.2.5.2 Local District Regulations
3.2.6 Summary
3.3 Noise Emissions
3.3.1 D_efinin.g Noise
3.3.2 Physical Properties of Sound
3.3.3 Measuring the Loudness of Sound
3.3.3.1 Loudness Description
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4.0
5.0
6.0
7.0
3.3.3.2 Sound Level Measurement
3.3.4 Noise in California
3.3.4.1 Noise Sources
3.3.4.2 Numbers of People Potentially Exposed: the Public
3.3.4.3 Numbers of Peopte Potentially Exposed: the Operator
3.3.5 Regulating Noise
3.3.5.1 Federal Law
3.3.5.2 _State_Law
3.3.5.3 Local Ordinances
3.3.6 Noise From Leaf Blowers
3.3.6.1 Bystander Noise Exposure
3.3.6.2 Operator Noise Exposure
3.3.7 Use of Hearing Protectors
3.3.8 Summary
Review of Health Effects
ParIiculate Matter
Carbon Monoxide
Unburned Fuel
4.1
4.2
4.3
4.4 Noise
4.4.1 Hearing and the Ear
4.4.2 Noise-Induced Hearing Loss
4.4.3 Effects on the Fetus and Newborn
4.4.4 Non-auditory Physiological Response
4.4.5 Interference with Communication
4.4.6 Interference with Sleep
4.4.7 Effects on Performance and Behavior
4.4.8 Annoyance and Community Response
4.4.9 Effects on Wildlife and Farm Animals
Potential Health and Environmental Impacts of Leaf Blowers
5.1 The Worker
5.1.1 Exhaust Emissions
5.1.2 Fugitive Dust Emissions
5.1.3 Noise
5.2 The Public-at-Large
5.2.1 Exhaust F.mis~iong
5.2.2 Fugitive Dust Emissions
5.2.3 Noise
Future Research
6.1 F.xhml~t F.mi.~.~iorm
6.2 Fugitive Dust Emissions
Future Technology for Leaf Blowers
7.1 En_ggine Technologies That Reduce Exhaust Emissigns
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8.0
9.0
7.1.1
7.1.2
7.1.3
7.1.4
7.1.5
Four-Stroke Engines
Fuel-Injected Two-Stroke Engines
Stratified Scavenging Two-Stroke Engines
Two-Stroke Engine with Compression Wave Technology
Two-Stroke Engines with Catalysts
7.2 Sound Reduction Technology
7.3 Methanol
7.4 Electric Equipment
7.5 Alternatives to Leaf Blowers
Bibliography
Appendices (Not available with this draft)
A
B
C
D
E
F
G
SCR 19
Public Outreach Activities
Ambient Air Quality Standards
Chemical Speciation Profile for Paved Road Dust
Physical Properties of Sound.and Loudness Measures
ANSI Standard for Leaf Blowers
Manufacturer-reported Noise Levels from Leaf Blowers
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1.0EXECUTIVESUMMARY
The Executive Summary will be prepared for the next draft of this report.
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2.0 INTRODUCTION
2.1 Senate Concurrent Resolution 19 ..Leaf Blowers
Senate Concurrent Resolution No. 19 (SCR 19) was introduced by Senator John Burton ~
February 23, 1999, and chaptered May 2!, 1999. The resolution requests the ARB to prepare and
submit a report to the Legislature on or before January 1, 2000, "summarizing the potential health
and environmental impacts of leaf blowers and including recommendations for alternatives to the
use of leaf blowers and alternative leaf blower technology if the state board determines that
alternatives are necessary:.." and requested that cities and counties refrain from enacting new
ordinances to prohibit leaf blower usage until after the ARB has submitted its report.The
Legislature, via SCR 19, mentions that there are questions and concerns about potential health
and environmental impacts from leaf blowers, and requests that ARB write the report to help to
answer these questions and clarify the debate. The goal of this report, then, is to summarize for
the California Legislature existing data on health and environmental impacts of leaf
blowers, to identify relevent questions not answered in the literature, andsuggest areas for
future research.
The resolution specifies that the report will include a comprehensive review of existing
studies of the impacts of leaf blowers on leaf blower operators and on the public at large, and of
the availability and actual use of protective equipment for leaf blowers. The receptors identified
are humans and the environment; sources of impacts are exhaust, noise, and dust. Because the
Legislature specified that AR]3 use existing information, staff conducted no new studies. In order
to locate existing data, staff conducted extensive literature searches, contacted potential resources
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and experts by telephone and e-mail, and notified the public that we were looking for information
via U.S. mail and through a web 19age devoted to the leaf blower report.
2.2 Health and Environmental Impacts
SCR 19 asks ARB to summarizepotential health and environmental impacts of leaf
blowers, and thus our first task is to determine what information and analysis would comprise a
summary of "health and environmental impacts." The methodology the ARB has used for this
report is dependent both on the objectives of SCR 19 and on the available data. As staff
discovered, in some .areas, such as exhaust emissions, we know.much about a hazard; ha other
areas, such as fugitive dust emissions, we know very little. For both fugitive dust and noise, there
are few or no data specifically on leaf blower impacts. For all hazards, there have been no dose-
response studies related to emissions from leaf blowers and we do not know how many people are
affected by those emissions. Therefore, s/aft determined to provide the Legislature with a report
that has elements of both impact and risk assessments, each of which is described below. The
body of the report, then, comprises four components: hazard identification, review of health
effects, characterization of the potential impacts of leaf blowers on operators and bystanders, and
suggested future research.
Life-cycle Impact Assessment Life-cycle impact assessment is the examination of
potential and actual environmental and human health effects related to the use of resources and
environmental releases (Fava et al. 1993). A product’s life-cycle is divided into the stages of raw
materials acquisition, manufacturin2, distribution/transportation, use/maintenance, recycling, and
waste management (Fava etal. 1991). In this case, the relevant stage of the life-cycle is
use/mainenance. Life-cycle impact assessment tends to focus on relative emission loadings and
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resources use and does not directly or quantitatively measure or predict potential effects or
identify a causal association with any effect. Identification of the significance and uncertainty of
data and analyses are important (Barnthouse 1998).
Risk Assessment A traditional risk assessment, on the other hand, seeks to directly and
quantitatively measure or predict causal effects. A risk assessment evaluates the toxic properties
of a chemical or other hazard, and the conditions of human exposure, in order to characterize the
nature of effects and determine the likelihood of adverse impacts (NRC 1983). The four
components of a risk assegsment are:
1.Hazard identification: Determine the identities and quantities of chemicals present, the
types of hazards they may produce, and the conditions under which exposure occurs.
2.Dose-response assessment: Describe the quantitative relationship between the amount of
exposure to a substance(dose) and the incidence of adverse effects (response).
3.Expom~re assessment: Identify the nature and size of the population exposed to the
substance and the magnitude and duration of their exposure.
4.Risk characterization: Integrate the data and analyses of the first three compenents to
determine the likelihood that humans(or other species) will experience any of the various
adverse effects assocatied with the substance.
The goal of risk assessment is the quantitative characterization of the risk, i~e., the
likelihood that a certain number of individuals will die or experience another adverse endpoint,
such as injury or disease. A risk assessment is ideally followed up by risk management, which is
the process of identifying, evaluating, selecting, and implementing ~ctions to reduce risk to human
health and ecosystems (Omenn, et al. 1997). While a risk assessment appears to be preferable
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because it allows us to assign an absolute value to the adverse impacts, a quantitative assessment
is difficult, if not impossible, to perform when data are limited.
2.3 Timeline
SCR 19 requests that ARB deliver this report to the Legislature by January 1, 2000. The
ARB’s governing board must review and approve the report before its delivery to the Legislature.
To allow time for review and comment on the report, it will be released to the Board and the
public in early November. Prior to this review, staff conducted two public workshops, on July 28,
1999, to discuss the method by which ARB proposed to conduct the study, and on September 28,
1999, to discuss the first public draft.
ACTIVITY
Delivery to the Legislature
Air Resources Board Public Heating
Public Notice and Report
Public Workshop to Review Draft
Public Workshop to Discuss Methodology
SCR 19 Chaptered
DATE
January 1, 2000
December 9, 1999
November 9, 1999
September 28, 1999
July 28, 1999
May 21, 1999
2.4 Public Outreach
Staff mailed a letter to about 1,200 people on June 28, 1999, announcing a public
workshop, to be held July 29, and requesting all available information on the health and
environmental impacts of leaf blowers. Also in June, staff posted a Leaf Blower Report website,
with links to the public workshop notice and the text of SCR 19. The website and letter provided
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the public with a contact address, telephone number, and e-mail address. Twenty-eight people
signed in at the workshop.
A second public workshop was announced by letter and on the Leaf Blower Report
website on September 2, 1999. The workshop was held September 28, 1999, to provide a forum
for discussion of the first public draft of the report. The first draft report was posted on the
website and~mailed to those who requested it.
In addition to the public workshops, staff met with representatives of the Outdoor Power
Equipment Institute (OPEI), the Portable Power Equipment Manufacturers Association
(PPEMA), the City of Los Angeles Department of Water and Power, various manufacturers,
Citizens for a Quieter Sacramento, and Zero Air Pollution. See Appendix B for a complete list of
telephone, in-person, and e-mail contacts.
2.5 History of the Leaf Blower and Local Ordinances
The leaf blower was invented by Japanese engineers in the early 1970s and introduced to
the United States as a lawn and garden maintenance tool. Soon after the leaf blower was
introduced into the U.S., its use was banned in two California cities, Carmel-by-the-Sea in 1975
and Beverly Hills in 1976, as a noise nuisance (CQS, 1999b). Nevertheless, by 1990, annual sales
were over 800,000 nationwide and the number of California cities that had banned use of leaf
blowers was up to five. Currently there are twenty California cities that have banned, or in the
case of Los Angeles, severly restricted, leaf blowers, and another 80 that have ordinances on the
books restricting either usage or noise level or both. Nationwide, two states, Arizona and New
Jersey, are considering statewide laws, and five other states have at least one city with a leaf
blower ordinance (IME 1999).
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The issues usually mentioned by people who object to leaf blowers are health impacts
from noise, air pollution, and dust. In addition, some have also argued that the leaf blower is bad
for plants because it is usually used to remove dead plant materials that would otherwise
contribute to soil health through decomposition (Smaus 1997). Professional gardening firms,
however, believe that the leaf blower is an essential, time-sa~ing tool that has enabled them to
offer services at a much lower cost than if they had to use rakes, brooms, and water to clean up
the landscape (CLCA 1999). Whether or not the use of leaf blowers saves on time and money
continues to be debated, with each side making claims for the efficiency or esthetics of leaf blower
use versus rakes and brooms. Cities that have not banned leaf blower use have produced studies
showing how expensive such a ban would be, while cities that have banned leaf blowers have
apparently not seen costs rise significantly (City of Palo Alto 1999, CQS 1999a).
Municipalities usually regulate leaf blowers as,public nuisances, in response to citizen
complaints (see, e.g., City of Palo Alto 1998a, 1998b, 1999; City of Los Angeles 1999). Two
reports were located that address environmental concerns: the Orange County Grand Jury. Report
(1999), and a series of reports written by the City Manager of Palo Alto (1999, 1998a, 1998b).
The City of Palo Alto reports have been produced in order to make recommendations to the City
Council on amending their existing ordinance. The Orange County Grand Jury took action to
make recommendations that would "improve the quality of life in Orange County," and
recommended that cities, school districts, community college districts, and the County stop using
gasoline-powered leaf blowers in their maintenance and clean-up operations. The major findings
of each are similar, and are listed in Table 1:
Table 1. Major Findings of the Orange County Grand Jury and City of Palo Alto
Orange County Grand Jury Report (1999)
"Toxic exhaust fumes and emissions are
created by gas-powered leaf blowers."
"The high-velocity air jets used in blowing
leaves whip up dust and pollutants. The
particulate matter (PM) swept into the air by
blowing leaves is composed of dust, fecal
matter, pesti6des, fungi, chemicals,
fertilizers, spores, and street dirt which
consists of lead and organic and elemental
carbon."
"Blower engines generage high noise
levels. Gasoline-powered leaf blower noise
is a danger to the health of the blower
operator and an annoyance to the non-
consenting citizens in the area of usage."
City of Palo Alto City Manager’s Report (1999)
"Gasoline-powered leaf blowers produce fuel
emissions that add to air pollution."
"Leaf blowers (gasoline and electric) blow
pollutants including dust, animal droppings, and
pesticides-into the air adding to pollutant
problems"
"Leaf blowers (gasoline and electric) do
produce noise Ievels that are offensive and
bothersome to some individuals."
In addition to the findings on exhaust emissions, dust, and noise, the City of Palo Alto
made three additional findings:
"Other garden equipment such as gasoline-powered lawn mowers, hedge trimmers, and
weed wackers also produce similar noise levels and present many of the same environmental
concerns."
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"While there are other types &tools that can be used, the majority of them require at least
30 to 50percent more time to complete the work compared to leaf blowers, and thus significantly
increase the costs to the City for clean up .of public facilities."
"Ordinances regulating the use of leaf blowers should be easily enforced and understood in
order to be effective and for compliance to occur."
As will be discussed in more detail later in this report, the findings in these two reports
about exhaust emissions and noise are substantiated in the scientific literature. The reports’
findings regarding dust emissions, however, were not documented or based on analysis of actual
emissions, but were based on "common sense" knowledge. The City of Palo Alto conducted
studies of noise levels from various pieces of equipment, following the ANSI standard when
testing leafblowers~ and surveyed their lawn and garden maintenance contractors, asking them to
project their costs to the City should they be prohibited from using leaf blowers. The contracts
were not competetively bid, however, thus the contractors were free to project rate raises without
fear of losing their contracts. The City’s final finding on the stucture of an ideal ordinance was
based on surveys of other cities and their experience with enforcing existing ordinances.
2.6 Overview of this Report
The main body of this report comprises five additional chapters, followed by the
bibliography and appendices. Chapter 3 decribes the hazards, as identified in SCR 19, from leaf
blowers. Exhaust emissions, fugitive dust emissions, and noise are covered in turn, along with
who is exposed to each hazard and how society has sought to control exposure to those hazards
through laws. Chapter 4 reviews health effects of each of the hazards, with exhaust emissions
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subdivided into particulate matter, carbon monoxide, and important constituents of unburned fuel.
Health effects from fugitive dust are covered in the subsection on particulate matter.
Chapter 5 summarizes the potential health and environmental impacts of leaf blowers,
attempting to sythesize the information presented in Chapters 3 and 4. Chapter 6 describes
suggested research that, if conducted, would alloW researchers to better understand the health and
environmental impacts. Finally, Chapter 7 describes engine technologies that could reduce exhaust
emissions, including electric power, and discusses methanol fuel and alternatives to leaf blowers.
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3.0 DESCRIPTION OF THE HAZARDS
This section of the report describes the three hazards identified by SCR 19 as resulting
from leaf blowers. There are undoubtably other hazards that could have been examined, such as
whole-body vibration, risk of burning from hot engine parts, or eye damage from blown debris,
but the California Legislature chose to limit the scope of this report. Exhaust emissions, noise, and
blown dust from leaf blowers have been singled out as the most important issues, as discussed in
section 2.5 of this report. Thus, the Legislature requested that ARB examinethe three hazards
that have been of most concern.
Hazard identification is the first step in an impact or risk assessment. ARB staffhave
conducted an impact assessment in three steps, the first of which considers the nature of the
hazard. In this section, then, each of the three identified hazards are examined in turn, exhaust
emissions, blown, or fugutive, dust emissions, and noise. For each, the hazard is described and
quantified. For noise, the number of people potentially exposed to the hazard is discussed; for
fugitive dust and exhaust emissions the number of people potentially impacted is assumed to be
the population of the state. Finally, in this section we also discuss laws that control the particular
hazard.
3.1 Exhaust Emissions
3.1.1. Characterization of Technology
Leaf blowers have traditionally been powered by two-stroke gasoline engines, and most
still are today) The two-stroke engine has several attributes that are advantageous for
1Ul~ess otherwise referenced, this section makes use of material in the ARB’s Small Off
Road Engine staff report and attachments, identified as MSC 98-02; 1998.
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applications such as leaf blowers. Two-stroke engines are lightweight in comparison to the power
they generate, and can be used with the engine in any position. Multi-positional operation is made
possible by mixing the lubricating oil with the fuel, thus, the engine is properly lubricated even
when operated at a steep angle or upside down.
Typical two-stroke designs feed more of the fuel/oil mixture than is necessary into the
combustion chamber. Through a process known as "scavenging." the incoming fuel enters the
combustion chamber as the exhaust is leaving. This timing overlap of intake and exhaust port
opening can result in as much as 30% of the fuel/oil mixture to be exhausted unburned. Thus, the
major pollutants from a two-stroke engine tend to be hydrocarbons, oil-based particulates, and
carbon monoxide. A two-stroke engine forms relatively little oxides of nitrogen emissions,
because the extra fuel absorbs the heat and keeps peak combustion temperatures low.
Additionally, there are some blowers that utilize four-stroke engines. These blowers are
typically "walk-behind" models, used to clean large parking lots and industrial facilities, rather
than lawns and driveways. Overall, the engines used in these blowers emit significantly lower
emissions than their two-stroke counterparts, with significantly lower levels of hydrocarbons and
particulate matter. These four-stroke blower engines have a significantly lower population than
the traditional two-stroke blowers and only peripherally fit the definition or commonly-accepted
meaning of the term "leaf blower." They are mentioned here only for completeness, but are not
otherwise addressed in this report.
3.1.2 Exhaust Emissions Inventory
3.1.2.1 Leaf Blower Population. The best estimates available indicate that there are
approximately 410,000 gasoline-powered blowers in use in the state today. This figure has been
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developed from information gathered through the development and implementation of ARB’s
small off-road engine regulation. Less than 5,000 of those use four-stroke engines.
Since the small off-road engine regulation does not apply to blowers powered by electric
motors, the data regarding the number of electric blowers are not as extensive. However,
information shared by the handheld power equipment industry indicates that approximately 60
percent of blowers sold are electric. This would indicate that there are approximately 600,000
electric blowers in California. Most &those would be dependent on the use of a power cord. It
must be stressed that the majority of the blower j~oj~ulation being electric does not imply that the
majority of usage is due to electric blowers. In fact, electric blowers are more likely to be used by
homeowners for occasional use, whereas virtually all commercial use involves engine-powered
blowers.
3.1.2.2 Emission Inventory. California’s emission inventory is an estimate of the amount
and types of pollutants emitted by all sources of air.pollution. The emission inventory method and
inputs for small off-road engines, with power ratings of less than 25 horsepower (hp), was
approved by the Board in 1998 (Table 2). Exhaust emissions from leaf’blowers contribute from
one to nine percent of the small-off road emissions, depending on the type of pollutant, based on
the 2000 emissions data. Exhaust emission standards for small off-road engines, which will be
implemented beginning in year 2000, will result in lower emissions in the future. By 2010, for
example, reactive organic gas (ROG) emissions are expected to shrink by 40% statewide, while
CO declines by 35% and PM10 drops 90%. The reductions reflect the replacement of today’s
blowers with cleaner blowers meeting the year 2000 standards.
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Table 2. Leaf Blower Exhaust Emissions, Statewide Inventory (tons per day)
Reactive Organic
Gases (ROG)
Carbon Monoxide
(co)
Fine Particulate
Matter (PM 10)
Leaf blowers
2000
7
15
0.2
Leaf blowers
2010
4.2
9.8
0.02
All Lawn &
Garden, 2000
¯ 50.24
434.99
1.05
All Small Off-
Road, 2000
80.07
1046.19
3.17
Although leaf blowers by themselves do not constitute a large portion of the inventory, it
should be emphasized that emissions from virtually all sources are being controlled at this time
and that portions of the state still fall short of meeting the federal ambient air quality standards.
Further emissions controls for these engines are not contemplated at this time, but the possibility
does exist. Nothing in this report should be construed as supporting or opposing any future action
to further control emissions from small two-stroke engines.
3.1.3 Regulating Exhaust Emissions
3.1.3.1 State Regulations. The California Clean Air Act, codified in the Health
and Safety Code Sections 43013 and 43018, was passed in 1988 and grants the ARB authority to
regulate off-road mobile source categories, including leaf blowers. The federal Clean Air Act
requires states to meet national ambient air quality standards (Appendix C). Because portions of
California do not meet some of these standards, the State regularly prepares a State
Implementation Plan, which specifies measures that will be adopted into law to meet the national
standards. Other feasible measures not specified in the state implementation plan may also be
adopted.
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In December 1990, the Board approved emission control regulations for new small
off-road engines used in leaf blowers and other applications. The regulations took effect in 1995,
and include exhaust emission standards, emissions test procedures, and provisions for warranty
and production compliance programs. In March of 1998, the ARB amended the standards to be
implemented with the 2000 model year. Table 3 illustrates how the standards compare with
uncontrolled engines for leaf blower engines between 20 and 50 cubic centimeters (cc) in
displacement. The few blowers above 50 cc comply with 1995-1999 standards of 120 + 4.0
g/bhp-hr HC+NOx and 300 g/bhp-hr CO. Note that there was no particulate matter standard for
1995-1999 model year leaf blowers, but that a standard will be imposed beginning with the 2000
model year.
Among other features of the small off-road engine regulations is a requirement that
production engines must be tested to ensure compliance. Examination of the certification data
confirms that manufacturers have been complying with the emissions regulations; in fact, engines
that have been identified as being used in blowers tend to emit hydrocarbons at levels that are 10
to 40 percent below the existing limits. This performance is consistent with engines used in string
trimmers_, edgers, and other handheld-type equipment, which are, in many cases, the same engine
models used in leaf blowers.
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Table 3
Exhaust Emissions for Leaf Blower Engines
(grams per brake-horsepower-hour)
Uncontrolled 1995-1999 Standards 2000 and later
Emissions Standards
HC+NOx 283 + 1.0 180 + 4.0 542
CO 9O8 6OO 400
PM 3.6 .__3 1.5
3.1.3.2 Federal Regulations. Although the federal regulations for mobile sources
have traditionally followed the ARB’s efforts, the U.S. EPA has been able to take advantage of
some developments following the ARB’s March 1998 Board hearing. Specifically, a vocal
opponent of the ARB’s standards reversed its position upon discovering another means of
compliance, specifically two-stroke engines equipped with compression wave technology.
Bolstered by this information, the U.S. EPA (1999b) has proposed standards for blowers and
other similar equipment that would be more stringent than the ARB standards. ARB plans a
general review of off-road engine technology by 2001, and will consider the implications of this
new technology in more detail then. A short description is included in "Future Technology"
(Chapter 7).
3.1.3.3 South Coast Air Quality Management District Emissions Credit
Program. The South Coast Air Quality Management District (SCAQMD), an extreme
non-attainment area for ozone, has promulgated Rule 1623 - Credits for Clean Lawn and Garden
2For yr 2000, the HC + NOx standards have been combined.
3There was no particulate standard for this time period.
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Equipment. Rule 1623 provides mobile source emission reduction credits for those who
voluntarily replace old high-polluting lawn and garden equipment with new low- or zero-emission
equipment or who sell new low- or zero-emission equipment without replacement. The intent of
the rule is to accelerate the retirement & old high-polluting equipment and increase the use of new
low- or zero-emission equipment. In 1990, volatile organic carbon emissions from lawn and
garden equipment in the South Coast Air Basin were 22 tons per day (SCAQMD 1996). To date,
no entity has applied for or received credits under Rule 1623 (V. Yardemian, pers. com.)
3.1.4 Summary
Exhaust emissions from leaf blowers consist of the following specific pollutants of
concern: reactive organic gases (ROG) from both burned and unburned fuel, and which combines
with other gases in the atmosphere to form ozone; carbon monoxide; fine particulate matter, and
other toxic chemicals in the unburned fuel. Exhaust emissions from these engines, however, have
been controlled since 1995 and will continue to be controlled in the future, with more stringent
standards taking effect in 2000. Manufacturers have developed several different methods to
comply with the standards. The exhaust emissions from leaf blowers are consistent with the
exhaust emissions of other, similar equipment, such as string trimmers. Manufacturers &leaf
blower engines have done an acceptable job certifying and producing engines that are below the
limits set by the Air Resources Board.
3.2.1.
3.2 FUGITIVE DUST EMISSIONS
Definition of Fugitive Dust Emissions
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"Blown dust" is the second of the hazards from leaf blowers specifically mentioned in SCR
19. For the purposes of this report, we will use the term "fugitive dust," which is more in line with
the terminology used by the ARB. From the Glossary of Air Pollution Terms, available on the
ARB’s website,4 the following definitions are useful:
Fugitive Dust: Dust particles that are introduced into the air through certain activities such
as soil cultivation, or vehicles operating on open fields or dirt roadways. A subset of
fugitive emissions.
Fugitive Emissions: Emissions not caught by a capture system (often due to equipment
leaks, evaporative processes, and windblown disturbances).
Particulate Matter (PM): Any material, except uncombined water, that exists in the solid
or liquid state in the atmosphere. The size of particulate matter can vary from coarse,
wind-blown dust particles to fine particle combustion products.
Fugitive dust is a subset of particulate matter, which is a complex mixture of large to small
particles that are directly emitted or formed in the air. Current control efforts focus on PM small
enough to be inhaled, generally those particles smaller than 10 micrometers (~m). So-called
coarse particles are those larger than 2.5/.zm in diameter, and are directly emitted from activities
that disturb the soil, including travel on roads, construction, mining, agriculture, and landfill
operations, plus windblown dust, pollen, spores, sea salts, and rubber from brake and tire wear.
Those with diameters smaller than 2.5 ~m are called fine particles. Fine particles remain
suspended in the air for long periods and can travel great distances. They are formed mostly from
combustion sources, such as vehicles, boilers, furnaces, and fires, with a small dust component.
4http ://arbis.arb.ca.gov/htrnl/gloss.htm
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Fine particles can be directly emitted as soot or formed in the atmosphere as combustion products
react with gases from other sources (Finlayson-Pitts & Pitts 1986).
Fugitive dust emissions from leaf blowers fall into the category of "uninventoried"
fugitive dust emissions and hence arenot included in the ARB’s emissions inventories. Asidefrom
a study conducted for the SCAQMD (Botsford et al. 1996) to determine whether fugitive dust
blown by leaf blowers was a "significant" source in the South Coast Air Basin, there has been no
research conducted to estimate dust emissions. ARB staff have, in this report, developed a
proposed methodology for estimating fugitive dust emissions from leaf blowers. The estimation
presented below begins with the assumptions and calculations contained in the study conducted
for the SCAQMD by AeroVironment (Botsford et al. 1996). Additional methodologies and data
have been reviewed and derived from the U.S. EPA document commonly termed AP-42, and
reports by the Midwest Research Institute; University of California, Riverside; and the Desert
Research Institute.
3.2.2 Calculating Leaf Blower Emissions
The fundamental premise in the calculations below is that leaf blowers are designed to
move relatively large materials such as leaves and other debris, and hence can also be expected to
entrain into the air much smaller particles, especially those below 30/.zm diameter, which are
termed PM30. Subsets ofPM30 inlcude PM10, with diameters below 10.urn, and PM2.5~ with
diameters below 2.5/~m. Particles below 30/.zm are not visible to the naked eye. Note that PM10
includes PM2.5 particles, and PM30 includes PM10 and PM2.5 particles.
3.2.2.1 Generation of Fugitive Dust by Leaf Blowers. The goal of a person using a leaf
blower is to move material such as leaves and debris; the leaf blower does this by moving
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relatively large volumes of air, typically between 350-700 cubic feet per minute, at a high wind
speed, typically 150 to 280 miles per hour (hurricane wind speed is >117 mph). While the intent
may not be to move dust, this air movement also suspends or resuspends the dust on the surface
being cleaned, because a typical surface to be cleaned is covered with a "layer" of dust that is
spread, probably non-uniformly, along the surface being cleaned. In order to calculate how much
fugitive dust is generated by the action of a blower, we assume that this "layer" of dust can be
represented by a single average number, the silt loading. This silt loading value, when Combined
with the amount of ground cleaned per unit time and the PM weight fractions, produces the
estimates of fugitive dust emissions from leaf blowers.
It is recognized and acknowledged that this analysis has been constrained by the language
of SRC 19, directing ARB staff to only use existing data, to be a first- or second-approximation
of reality. However, common experience indicates that a leaf blower will certainly entrain small
particles in the air. The question is: what should those silt loading and size-segregated PM weight
fractions be? This section presents the best estimate using existing data.
3.2.2.2 Size Segregation of Particulate Matter. PM emissions are subdivided
into the following three categories, operator emissions, local emissions, and regional emissions.
They are differentiated as follows:
1) Operator emissions. PM30 emissions will be used to estimate "operator" PM
emissions; PM30-sized particles have relatively short settling times, on the order of minutes to a
couple of hours, maximum (Finlayson-Pitts and Pitts 1986, Gillies et al. 1996, Seinfeld and Pandis
1998). These would be emissions to which the leaf blower operator and passersby would be
exposed.
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2) Local emissions. PM10 emissions will be used to estimate "local" PM emissions;
PM10 emissions may remain suspended for hours to days in the atmosphere (Finlayson-Pitts and
Pitts 1986, Gillies et al. 199,6, Seinfeld and Pandis 1998). These emissions would be emissions to
which persons in the near-downwind-vicinity would be exposed, for example, residents whose
lawns are being serviced and their neighbors, persons in commercial buildings whose landscapes
are being maintained or serviced, and persons within a few blocks of the source.
3) Regional emissions. PM2.5 emissions may remain suspended for as long as a week or
more (Finlayson-Pitts andPitts 1986, Gillies,et al. 1996, Seinfeld and Pandis 1998), and hence can
be considered as contributors to "regional" PM emissions over a county or air basin.
3.2.2.3 Calculation Assumptions. The method presented uses the following
assumptions.
1) Methods used for estimating wind blown dust for paved roads can be applied to
estimating fugitive dust emissions from leaf blowers. That is, one can use an "AP-42" type (U.S.
EPA 1997) of approach that calculates dust emissions based on the "silt loading" of the street
surface(s) in question.
2) The typical leaf blower generates sufficient ’wind speed’ to cause sidewalk/roadway
dust, in particular, particles 30 micrometers or less in aerodynamic diameter, to become airborne.
With nozzle air velocities from 120 to 180 mph, wind speed at the ground would range from 90
mph to 24 mph, according to the AeroVironment study (Botsford et al. 1996).
3) Currently available paved roadside/roadway and gutter silt loadings can be used to
calculate emissions from leaf blowers. The actual silt loading values used here are drawn from the
ARB’s Technical Support Division (ARB 1997a).
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4) The size fractions for PM30, PM10, and PM2.5 for paved road dust can be used to
calculate emissions from leaf blowers. After consulting Dr. Gregory Muleski at the Midwst
Research Institute, staff decided to use the ratio of’k’ factor values to estimate the weight fraction
&windblown dust for leaf blower usage. The "k" factor is a dimensionless value that represents
the percentage of the total dust loading that is of a certain size fraction.
3.2;2.4 Calculation Methodology. The specific emission factor calculation is as
follows:
P1VI~.~ Emissions = sL x Q x f~z~
where:
PM~.~ Emissions = PM30, or PM10, or PM2.5 emissions
s = silt loading fraction,
L = total dust/material loading
sL = s x L = silt loading for the area in question
Q = amount of ground cleaned per unit time
~== PM30, or PM10, or PM2.5 fraction &total dust loading content
Fugitive dust emissions will be estimated for commercial and residential usage. Leaf
blowers are used both in residential areas, for lawn and garden care, and commercial areas, such
as industrial parks and office complexes, and given that these areas are expected to have different
total dust/material loadings and silt loadings, estimates for both residential and commercial leaf
blower usage have been prepared.
The following silt loading values were selected from published silt loadings that ranged
between 0.02 and 557 grams per square meter (ARB1997a, U.S. EPA 1997, Venkatram et al.
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1998). The values selected were based on engineering judgement, rather than on an average of
roadway silt loadings. A straight arithmetic average would have been dominated by the few values
in the hundreds of grams per square meter. Instead, values were selected based on average values
selected from the literature and discussions with persons with background in the field of fugitive
dust emissions.
Commercial area silt loading, therefore, is assumed to be 2.0 g/m2; residential area silt
loading is assumed to be 0.035 g/m-’. The population and usage data, obtained from the ARB
Mobil~ Source Control Division, Emissions Analysis Branch, indicate that commercial use
accounts for 74.5 % and residential use accounts for 25.5% of per-hour usage. PM10 is assumed
to be 19 percent of the weight fraction of the silt, and PM2.5 represents 9 % of the silt weight
fraction. The amount of ground cleaned per unit time, Q, is assumed to equal 1,600 m’-/hr.
3.2.3 Characterization of Fugitive Dust Emissions.
This section includes results from thispresent analysis, as well as results from previous
estimates prepared by the ARB and others. For reference, this section begins with two previous
leaf bl ow2,r ,emi .~si ons e~tirnzto_~.
3.2.3.1 Previous Emissions Estimates: ARB, 1991. The ARB’s Technical
Support Division, in a July 9, 1991 response to a request from Richard G. Johnson, Chief of the
Air Quality Management Division at the Sacramento Metropolitan Air Quality Management
District (SMAQMD), prepared a per-leaf blower emissions estimate, in grams per hour of dust
(McGuire 1991). PM10 emissions were reported as being 1,180 g/hr, or 2.6 lb/hr. If this emission
factor is combined with current statewide hours-of-operation data of 97,302 hr/day of leaf blower
usage, this would produce an emission inventory of 126.5 tpd of PM10.
3.2.3.2 Previous Emissions Estimates: SMAQMD. Sacramento Metropolitan Air
Quality Metropolitan District (SMAQMD) staff (Covell 1998) estimated that "Dust Emissions
(leaf blowers only)" are 3.2 tpd in Sacramento County. The memo included commercial and
residential leaf blower populations (1,750 commercial and 15,750 residential), and hours of use
(275 hr/yr for commercial and 10 hr/yr for residential). Using these values one can "back
calculate" the assumed g!hr emission factor for ’,particulate matter". The resulting emission factor
is 1,680 g/hr, or 3.7 lb/hr. The resulting statewide emission inventory is 180 tpd.
3.2.3.3 Emission Factors - This Study. Two emission factors have been
calculated (Table 4): one for commercial.usage, whichassumes a higher silt loading of 2.0 g/m2,
and a second one for residential.usage, which assumes a low silt loading of 0.03 5 g/m2.
Table 4. Estimated Emission Factors, This Study
grams per hour, g/hr (pounds per hours, lb/hr)
Emission Factor
Total Suspended Particulate
PM10
PM2.5
Commercial
3200 (7.04)
608 (1.34)
288(0.63)
Residential
56 (0.12)
10.64 (0.02)
5.04(0.01)
3.2.3.4 Statewide Emissions Inventory - This Study. The statewide emissions
inventory has been estimated by combining the hours of operation by equipment category
(residential and commercial). Residential usage includes fugitive dust emissions contribution from
electric leaf blowers, of which there are an estimated 600,000 in California: all electric leaf
blowers are assumed to be in residential usage.
Table 5. Statewide Emissions Inventory, This Study
tons per day (tpd)
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Emissions Inventory Commercial Residential Total
Total Suspended Particulates 255.5 2.5 258
PM10 48.5 0.5 49.0
PM2.5 23.0 0.2 2312
3.2.3.5 Comparison of Emission Factors and Inventories. The 1996 statewide
estimates for paved road dust, unpaved road dust, and fugitive windblown dust are 400 tpd, 610
tpd, and 310 tpd, respectively. Thus, the total suspended particulate emissions from this study are
on a scale with these three sources. The entire 1996 PM10 emission inventory, which does not
include leaf blower dust emissions, was 2,400 tpd. The contribution from leaf blower fugitive dust
is, therefore, estimated to be about two percent of the statewide PM10 emissions inventory. A
finer scale analysis, by air district, would shed light on whether or not dryer areas of the state
experience a greater emissions impact than wetter areas. Unfortunately, ARB lacks the data
necessary to make a finer scale, air district by air district, analysis for this study. It must be
stressed that this estimate is highly dependent on silt loading values, which have not been
specifically defined for leaf blower usage, and thus these estimates should be considered to be
first-order approximations.
Comparing the estimates derived in this study with the previous ARB estimate (McGuire
1991), we find that the major difference is the weight fraction of total suspended particulates that
comprises PM10. The 1991 estimated emission factor for PMtsp was 5.7 lb/hr, or 2585 g/hr,
comparable to this study’s emission estimate of 7 lb/hr, or 3200 g/hr. In the earlier study,
however, ARB assumed that 45% of the PMtsp was PM10, whereas this study assumes 19%.
3.2.4 Chemical Composition
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In keeping with the direction to use existing data, the use of ARB’s size-segregated
chemical speciation profiles for paved road dust was considered to chemically characterize leaf
blower PM emissions.However, because of the great uncertainty as to the composition of leaf
blower dust, paved road dust chemical characteristics were not used in estimating health impacts,
but are presented in Appendix D for information. In addition to soil particles, paved road dust
emissions contain contributions from tire and brake wear particles. A Fresno County Air Pollution
report noted that street sweepings in Fresno were found to contain arsenic, chromium, lead,
mercury and other metals.The ARB’s own chemical speciation profiles for paved road dust also
show small percentages of these substances.
3.2.5 Regulating Fugitive Dust Emissions
Fugitive dust emissions are generally regulated as a nuisance, although PM10 and PM2.5
are specifically addressed through the state planning process as criteria air. pollutants. There are
no explicit federal, state, or local regulations governing leaf blower fugitive dust emissions.
3.2.5.1 State and Federal I~M10 and PM2~5 Standards. Ttte California.and Fedgxal
ambient air quality standards for PM10 and PM2.5 are located in Appendix C. Any state that has
air basins not in attainment for the standards must submit a plan to U.S. EPA on how they will
achieve compliance. For California, most of the state violates the PM10 standard; attainment
status has not yet been determined for the new PM2.5 standard Oaromulgated July 18, 1997)..
California, and its air districts, is therefore required to control sources of PM10, including fugitive
dust.
3.2.5.2 Local District Regulations. Many air districts have a fugitive dust control
rule that prohibits activities that generate dust beyond the property line of an operation. For
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example, the SCAQMD Rule 403 states: "A person shall not cause or allow the emissions of
fugitive dust from any active operation, oaaen storage.pile, or undisturbed surface area such that
the presence of such dust remains visible in the atmosphere beyond the property line of the
emission source." In addition, rules may place limits on the amount ofPM10 that can be detected
downwind of an operation that generates fugitive dust; for SCAQMD that limit is 50 #g/m3
[SCAQMD Rule 403]. The Mojave AQMD limits PM emissions to 100/.zg/m3 [Mojave AQMD
Rule 403]. Others, such as the San Joaquin Unified APCD, define and limit visible emissions
(40% opacity) from activities that generate fugitive dust emissions [SJUAPCD Rule 8020].
Finally, another approach is to simply request individuals take "reasonable precautions" to prevent
visible particulate matter emissions from moving beyond the property from which the emissions
originate [Great Basin Unified APCD Rule 401].
3.2.6 Summary
The data presented indicate that the PM10 emissions impact from fugitive dust suspended
by leaf blowers are small, but not insignificant, at about 2 percent of the total PM10 inventory.
Previous fugitive dust estimates are in the same neighborhood as the estimates developed and
presented here. For example, the ARB’s Technical Support Division estimated statewide fugitive
dust emissions to be about 5 percent of the statewide PM10 emission inventory in 1991, and the
SMAQMD (1998) estimated leaf blower fugitive dust emissions to be about 2 percent of the
Sacramento county PM10 air burden.
To what extent leaf blowers are efficient mechanisms for entraining PM30 and smaller
particles in ambient air can only be demonstrated empirically, using real leaf blowers to clean
selected surfaces that are representative of actual leaf blower usage. A more definitive estimate of
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leaf blower fugitive dust emissions will require a research project to determine and verify
appropriate calculation parameters, determine representative silt loadings, determine actual
fugitive dust emissions through source testing, and determine the chemical composition of leaf
blower generated fugitive dust.
3.3 NOISE EMISSIONS
3.3.1 Defining Noise
The third of the hazards from leaf blowers identified in SCR 19 is noise. Noise is the
general term for any loud, unmusical, disagreeable, or unwanted sound. Noise can damage
hearing, interrupt communication, disturb rest and sleep, and cause psychological and
physiological changes that may lead to poor health (WHO 1980). The adverse physiological
effects of noise include damage to hearing and may include elevated blood pressure and changes
in body chemistry leading to irritability and anxiety. Psychological effects range from annoyance
to interference with communication, sleep, work performance, and behavior (Kryter 1994). In this
report, noise will be used to refer both to unwanted sounds and sounds that damage hearing. The
two qualities, although related, do not always occur together.
The effects of sound on the ear are determined by its quality, which consists of the
duration, intensity, frequency, and overtone structure, and the psychoacoustic variables of pitch,
loudness, and tone quality or timbre, of the sound. Long duration, high intensity sounds are the
most damaging and usually perceived as the most annoying. High frequency sounds, up to the
limit of hearing, tend to be more annoying and potentially more hazardous than low frequency
sounds. Intermittent sounds appear to be less damaging than continuous noise because the ear
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appears to be able to recover, or heal, during intervening quiet periods. Random, intermittent
sounds, however, may be more annoying, although not necessarily hazardous, because of their
unpredictability (Suter 1991).
The context of the sound is also important. While certain sounds may be desirable to some
people, for example, music at an outdoor party, they may be considered noise by others, for
example, those trying to sleep. Even desirable sounds, such as loud music, may cause damage to
hearing and would be considered noise in this context. Thus, not only do loudness, .pitch, and
impulsiveness of sound determine whether the sound is "noise," but also the time of day, duration,
control (or lack thereof), and even one’s personality determine whether sounds are unwanted or
not.
The physical and psychoacoustic characteristics of sound, and thus noise, are described in
more detail in Appendix E. The discussion is focused on information necessary for the reader to
understand how sound is measured, and clarify measures of leaf blower sound. The interested
reader is referred for more information to any physics or acoustic reference book, or the works
referred to herein.
3.3.3 Measuring the Loudness of Sound
The weakest intensity of sound a health human ear can detect has an amplitude of 20
millionths of a Pascal5 (20 gl?a). The loudest sound the human ear can tolerate, the threshold of
pain, has an amplitude one million times larger, or 200,000,000 gPa. The range of sound intensity
between the faintest and the loudest audible sounds is so large that sound pressures are expressed
5Other units used to represent an equivalent sound pressure include 0.0002 #bar, 0.0002
dyne/cm2, and 20 ~zN/m2.
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using a logarithmically compressed scale, termed the decibel (dB) scale. The decibel is simply a
unit of comparison between two sound pressures. In most cases, the reference sound pressure is
the acoustical zero, or the lower limit of hearing. The decibel scale converts sound pressure levels
(SPL) to a logarithmic scale, relative to 20/~Pa.
SPL, dB = 10 loglo (P2/Po2)
Where P is the pressure fluctuation in Pascals,
Po is the reference pressure; usually 20 ~Pa.
(Insert figure illusti-ating the relationship between Pa, riB, and qualitative measures)
Thus, from this relationship, each doubling of sound pressure levels results in an increase
of 6 riB. From the relationship, above, between sound intensity and distance, we find also that
doubling the distance between the speaker (source) and listener.(receiver), drops the level of the
sound by approximately 6 riB. Sound pressure levels are not directly additive, however, but must
first be expressed as mean square pressures before adding (WHO 1980). The equation is as
follows:
SPL = 10 loglo [lOSW~/1° + 10sw~jl°_ + ....+ 10SV~x/~°]
For example, if two sound sources have SPLs of 80 dB and 90 dB, then the resulting sound
pressure is 90.4 dB:
SPL = 10 log10 [108 + 109] = 90.4 dB
Adding two sounds with the same SPL, for example 90 riB, increases the total SPL by 3 dB, for
example to 93 dB.
3.3.3.1 Loudness description. Sound pressure level, however, does not completely
describe loudness, which is a subjective perception of sound intensity. Loudness increases with
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intensity, but is also dependant on frequency. Thus the human ear may not perceive a six dB
increase as twice as loud. In general, people are more sensitive to sounds in the middle of the
range of hearing, from around 200 Hz to 5000 Hz. Fletcher and Munson (1933) first established
the 1000-Hz tone as the standard sound against which other tones would be judged for loudness.
Later, Stevens (1955) proposed that the unit of loudness be termed the sone, and that one sone be
ascribed to a 1000-Hz tone set at a SPL of 40 dB under specified listening conditions. On the
sone scale, a sound twice as loud as one sone would be two sones, four times as loud would be
four sones, and so on. Equal loudness contours, identified in units of phons, demonstrate how the
SPL, in dB, of a tone must be varied to maintain the perception of constant loudness.
Ideally, sound measurement meters would give a reading equal to loudness in phons, but
because phons are based on human perception, and perception process will vary from individual
to individual, this is notpractical for most purposes. While standards for measurement in phons
have been developed, they are only used under specific circumstances when high precision is
required (WHO 1980). For practical, purposes, loudness is recorded in decibels, and measured by
applying a filter that weights sound pressure level measurements as a function of frequency,
approximately in accordance with the frequency response characteristics of the human ear.
Several weighting systems have been developed, but the one in most common use is the A-
weighted filter. The A-filter provides the highest correlation between physical measurements and
subjective evaluations of the loudness of noise. EPA’s Office of Noise Abatement and Control
recommended A-filter weighting to describe environmental noise because it is "convenient to use,
accurate for most purposes, and is used extensively throughout the world (EPA 1979)." Levels
are commonly expressed as dBA.
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3.3.3.2 Sound level measurement. The American National Standards Institute,
Inc. (ANSI) has developed a method for measuring the sound levels from leaf blowers. The
purpose of the standard method is to establish sound level labeling requirements for leaf blowers
applicable to noise received by bystanders. The standard also includes requirements for safety
precautions to be included in manuals for use by operators (ANSI 1996). The ANSI standard
specifies a test area in a field in which natural ground cover does not exceed three inches in height
and which is free of any large reflecting surfaces for a minimum of 100 ft from the blower (see
Appendix F). The sound level meter must be set for slow response and the A-weighting network.
Once the blower is adjusted and running properly, the receiver (microphone) is set up 50 ft from
the operator and 4 ft above ground. Sound level readings are taken in a circle every 45 degrees
for a total of eight readings, as either the operator rotates or the microphone is moved. The eight
readings are then averaged and reported to the nearest decibel.
Although in wide use, the method has been criticized as sometimes generating
unreproducible results. Typical comments expressed in meetings with ARB staff were to the effect
that the manufacturer-reported sound levels for leaf blowers are often lower than those obtained
by some third party testers. Indeed, Consumer’s Union, which tests products and publishes
Con~tmer Reports, reported in its April 1997 issue that the Echo PB46LN, which Echo lists as a
quiet 65 dBA, tested at 69.5 dBA, only slighty quieter than most other leaf blowers (Consumer
Reports, 1997a). This issue has prompted the industry to reexamine the ANSI standard, and it is
in the process of being revised (Dunaway 1999). Other comments about the method criticize the
fundamental requirements for testing in an open field, with no reflecting surface for 100 ft, and the
receiver 50 ft away, as being unrealistic and unrepresentative of real-world use (Allen 1999).
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While the ANSI method yields sound level exposures for a bystander, the noise level
exposure for the operator is measured using an audiodosimeter. For occupational exposures, the
dosimeter reports the noise dose as a percentage relative to the permissible exposure level of 90
dBA (8 CCR General Industry Safety Orders, Article 105, Appendix A; 29 CFR §1910.25). The
eight-hour time-weighted average sound level experienced by the worker is then calculated from
the dose, using a formula specified in regulations. Additional specifications can be found in the
OSHA and Cal/OSHA Technical Manuals.6
3.3.4 Noise in California
3.3.4.1 Noise Sources. The major sources of noise today are likely the same as
they were twenty or more years ago when the U.S. EPA reported that the dominant sources for
outdoor noise in urban residential settings were motor vehicles, aircraft, and voices (U. S. EPA
1974). In order to the examine the sources of noise impacting the American population, the U.S.
EPA contracted for a study of noise and the number of people exposed to noise. The study
focused on man-made mechanical noises, excluding other human voices and animals. The results
ranked major sources, by number of people exposed, as road traffic, aircraft, construction,
railroads, and industrial equipment and activities (U.S. EPA 1981b).
3.3.4.2 Numbers of People Potentially Exposed: the Public. It is not possible to
state with any certainty how many ~people in California are exposed to noise from leaf blowers.
Indeed, the most recent nationwide estimate of the number of people exposed to noise from
various sources dates from 1981. In that study, the U.S. EPA estimated that 730,000 people were
6OSHA’s Technical Manual is available on their website (www.osha.gov) and noise
measurement is in Section I~ Chapter 5. Cal/OSHA’s manual is available from Cal/OSHA
directly.
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exposed to noise from leaf blowers above the day-night average sound level of 45 dBA (U.S.
EPA 1981). The use of leaf blowers has grown since 1980, however, and thus these numbers
cannot be scaled for an estimate of the number of Californians exposed to leaf blower noise today.
As California’s population has grown almost 41% since 1970 (CDF 1998, CDF 1999),
population density, and thus noise exposure, has increased. California classifies counties as being
metropolitan or non-metropolitan, based on the Bureau of the Census’s categorization of standard
metropolitan statistical areas as containing or being close to a large city. As of January 1, 1999,
the thirty-four metropolitan counties comprise 96.7% of California’s population, or about 32.67
million people. The population of Californians who live in non-metropolitan counties, while small
at 3.3% of the total, or 1.11 million people, has increased faster than the population in
metropolitan counties (47.1% increase versus 40.5% increase, 1970-1999) and thus even noise
exposures in the lowest populated counties have likely increased over the past thirty years.
Unfortunately, without a comprehensive and current survey of noise exposures in
California, it is not possible to determine, from available data, how many Californians are exposed
to noise, and in particular exposed to noise from leaf blowers. The only conclusion is that the
number of people affected by noise is likely increasing as population density increases even in
non-metropolitan areas of the state. How many people are exposed to, and annoyed by, noise
from leaf blowers is a question for future research.
3.3.4.3 Numbers of People Potentially Exposed: the Operator. One can assume
that all gardeners are exposed to the noise from leaf blowers, either as an operator or from
worldng in close proximity to the operator. From the California database of employees covered by
unemployment insurance, in the fourth quarter of 1998 there were 59,489 workers reported by
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6790 firms, in the SIC Code 0782, Lawn and Garden Services (M. Rippey, pers. comm). This
number is assumed to be the lower bound of those exposed, as there are likely many workers
employed in the underground economy, who neither report their earnings nor are covered by
unemployment insurance. Future research could test the hypothesis that all lawn and garden
service workers are exposed, as operators or from working in close proximity, to the noise from
leaf blowers.
3.3.5 Regulating Noise
3.3.5.1 Federal Law. The Noise Control Act of 1972 established a statutory
mandated national policy "to promote an environment for all Americans free from noise that
jeopardizes their public health and welfare." The Office of Noise Abatement and Control was
established within the EPA to carry out the mandates of the Noise Control Act. The Office of
Noise Abatement and Control published public health and welfare criteria; sponsored an
international conference; examined dose-response relationships for noise and its effects; identified
safe levels of noise; promulgated noise regulations; funded research; and assisted state and local
offices of noise control; until it was defunded in 1981 and 1982 by the Reagan administration
(Surer 1991; Shapiro 1991). In its almost ten years of operation, EPA produced several
documents that are still relevant, if dated, today.
The heating of workers is protected by regulations promulgated under the Occupational
Safety and Health Act of 1970. As California employers fall under California’s equivalent
program, hearing protection law will be covered below under state law.
3.3.5.2 .State.La~. California.enactedthe .Noise.Control Act of 1973 to "establish
a means for effective coordination of state activities in noise control and to take such action as
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will be necessary..." [HSC §46000(g)]; the office was established within the Califomia
Department of Health Services. One of the primary functions of the office was to provide
assistance to local governmental entities that develop and implement noise abatement procedures,
and several guidelines were written. The office, however, was defunded by statute beginning in
the 1993-1994 fiscal year. Very little remains of the office, and no guidelines were obtained or
suggested as relevant for this report.
California’s counterpart to OSHA, the Cal/OSHA, has a General Industry Safety Order [8
CCR Article 105 §5095-5100] for the control of noise exposure that is very similar to the federal
OSHA regulations. Employers are required to provide employees with heating protection when
noise exposure exceeds 90 dBA in an eight-hour work day; as noise levels increase, the allowable
exposure duration also decreases. The permitted duration for an employee exposed to 103 dBA,
for example, is one hour and nineteen minutes in a work day [8 CCR §5096 .(a)(b)]. Employers
are allowed to use personal protective equipment to reduce sound level exposures if
administrative or engineering controls are not feasible or fail to reduce sound levels within
permissible levels. When sound level exposure exceeds 85 dBA for an 8-hour time-weighted
average, employers are required to provide a hearing conservation program at no cost to
employees. The hearing conservation program includes audiometric testing of heating, provision
of hearing protectors, training, and record keeping.
3.3.5.3 Local Ordinances. In contrast to the low level of activity on noise control
at the federal and state levels, local California dries and counties have been very active in
regulating and enforcing noise standards. About twenty cities have banned the use of gasoline-
powered, or gasoline- and electric-powered leaf blowers, from use within their city limits (City of
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Palo Alto 1999). If you include the City of Los Angeles, which has a very restrictive ordinance
that works like a ban, about 13% of Californians live in cities that ban the use of leaf blowers, and
six of the ten largest California cities have ordinances that restrict or ban leaf blowers. All
together, about one hundred California cities have ordinances that restrict either leaf blowers
all gardening equipment generally, including the cities with bans on leaf blowerspecifically or
use.
The restrictions on leaf blowers fall into four basic categories, with many cities employing
a combination of approaches: time of day/day of week, noise levels, specific areas, and
educational (City of Palo Alt0 1999). Time of day/day ofweek ordinances are the most common
and are used to control when leaf blowers can be operated. Typically, hours of use are restricted
to times between 7:00 a.m. and 7:00 p.m., and days of use are either Monday through Friday or
Monday through Saturday, and sometimes including Sunday, with shorter hours on the weekend,
based on the assumption that leaf blower noise is most offensive during the evening and night time
hours, and on the weekend. There may be exceptions for homeowners doing their own yardwork
and for work in commercial areas. Time of day/day of week ordinances are relatively easy to
enforce. A problem with these ordinances, however, is that they ignore the needs for quiet during
the day of babies, young children, and their caretakers; day-sleepers; the ill; the retired; and a
growing population of those who telecommute.
Some cities regulate leaf blower use based on noise levels recorded at a specified distance
from the operator. Palos Verdes Estates and Davis, for example, set the noise level at 70 dBA at
50 f-t, and Newport Beach and San Diego have a 65 dBA at 50 ft restriction. Davis allows single-
family homeowners to avoid the restriction if the leaf blower is operated for less than ten minutes.
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Palos Verdes Estates requires blowers to be tested and certified by the city. Otherwise, a noise
level restriction is very difficult to enforce as it would require the enforcement officers to carry
and be trained in the use of sound level meters. These rules target the control of noise from
blowers, and, if effectively enforced could protect those who are home during the day and thus
are not protected by the time of day/day of week ordinances.
Recognizing that leaf blowers are often perceived as most offensive when used in
residential areas, many cities stipulate usage restrictions only in residential areas, or within a
certain distance of residential areas. The distance restrictions prohibiting the use of leaf blowers
range from 100 ft, in Foster City, to 500 ft, in Los Angeles, from residential areas. This type of
ordinance protects those who are at home and in need of quiet during the day, but does not
address issues of those who work and recreate in commercial or other non-residential areas.
Cities sometimes couple area restrictions with user guidelines, such as prohibitions on
blowing debris onto adjacent properties, and require operators be educated on the proper use of
leaf blowgrs so.as.to minimize.noJ_~ levels~ud.emvironmental issues. These educational
approaches are generally not oriented towards enforcement, but seek to change operator
behavior. Educational approaches are often endorsed by landscapers and manufacturers, who
believe that much of the discord over leaf blower usage originates with the few gardeners who use
them incorrectly or inconsiderately. For example, an organization calling itself "LINK" or
"Landscapers Involved With Neighborhoods and Kids" promotes educating operators to use their
leaf blowers at half-throttle within 150 ft of homes (LINK 1999).
3.3.6 Noise From Leaf Blowers
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In a survey of Southern Californian gardeners by a consumer products manufacturer
(Anon 1999), the top three ranked attributes of a desirable leaf blower were, in order, powerful,
quiet, and light-weight. Important features were identified as "backpack mounted," "noise below
legal limits," and "variable speed." When asked what they don’t like about their leaf blowers, the
most commonly cited problem was "noise." Taken together, these answers suggest that loud noise
from leaf blowers is not only an issue for the public, but is also a major issue of concern for the
gardeners who use them.
Manufacturer-reported noise levels from leaf blowers are summarized in Appendix G; all
reported noise levels are assumed to have been measured following the ANSI standard method,
with the receiver 50 ft from the blower. The reported levels are based on personal
communications with manufacturers, trade association representatives, or statements in
promotional literature. Although the manufacturers do not report personal exposure data for the
operator, the instruction manuals received with leaf blowers, do suggest that the operator wear
hearing protection at all times.
3.3.6.1 Bystander noise exposure. For backpack and hand held blowers, sound
levels range from a reported relatively quiet 62 dBA to a very noisy 75 dBA. Beating in mind the
logarithmic decibel scale, the difference in a leaf blower at 62 dBA and one at 75 dBA, a 13 dBA
range, represents more than a quadrupling of the sound pressure level, and would be perceived by
a listener as two to four times as loud. The rule of thumb is that, while each six dB increase or
decrease represents a doubling Of sound pressure level, the listener will perceive a ten dB increase
as twice as loud (MPCA 1987).
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There are presently three gasoline-powered backpack leaf blowers that are reported by
their manufacturers to be very quiet: the Echo PB46LN (65 dBA), the Maruyama BL4500SP (62
dBA), and the Toro BP6900 (62 dBA). For backpack leaf blowers, Echo sells slightly under one-
third of the total number of backblowers sold. In 1996, the most popular Echo backpack leaf
blower, based on sales, was the Echo PB-400E, one of the noisiest at 74 dBA. By 1999, however,
the quieter PB46LN had surpassed the PB-400E in sales (Will, L., pers. com.). These data are not
surprising especially as the purchasers are presumably the same professionals who identified noise
as one of their biggest issues in the survey discussed above.
The range of reported sound levels for hand held blowers is roughly the same as for back
pack blowers, from 63 dBA to 75 dBA. The. quietest hand held models are electric-powered: the
RedMax ’°Vr0om," at 63 dBA, and the Stihl BGE 60, also at 63 dBA. Some manufacturers, such
as Husqvama, Stihl, Ryobi, and Toro, did not report the sound levels of most of their models in
materials available to the ARB.
Perhaps because the low noise models represent a great leap in noise control, the
manufacturer reported levels have been challenged. The Echo PB46 LN was the first quiet leaf
blower on the market, and its claim to be the quietest backpack blower was tested by Consumer’s
Union, the publisher of Consumer Reports. As mentioned earlier, the sound level reported in
Consumer Reports (1997) was 69.5 dBA, only slightly quieter than many other models on the
market at the time. The City of Palo Alto (1998a, and Johnson, L., Palo Alto, pers. comm) tested
the Echo PB46 LN and several other leaf blowers. In their study, the Echo PB46 LN tested at 70
dBA and the Maruyama BL 4500 SP tested at 69 dBA. However, the noisy Echo PB-400E,
reported by the manufacturer at 74 dBA, also tested noisier at 77.6 dBA. Based on the City of
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Palo Alto tests, then, the "quiet" leaf blowers were about half as loud as the "noisy" blower.
Manufacturers are now discussing having their sound testing conducted by an independent third
party, at least in part to address the concerns about differences between test results, in addition to
revising the ANSI test method, as mentioned earlier.
3.3.6.2 Operator Noise Exposure. Noise levels at the leaf blower operator’s ear were not
made available to the Air Resources Board by manufacturers and little has been published on leaf
blower noise exposure. The League for the Hard of Hearing (1999) publishes a fact sheet in which
the noise level of a leaf blower is listed as 110 dBA. Clark (1991) reported that one model by
Weedeater emitted a maximum level of 110-112 dBA and an equivalent A-weighted sound level
(L ~q) of 103.6 dBA. This leaf blower model, however, is no longer available and these data may
not be comparable to today’s leaf blowers.
A more current study of leaf blower noise was located. Schulze and Lucchesi (1997), in an
unpublished conference presentation, reported the range and average sound pressure level from
four leaf blowers. The four leaf blowers were unidentified models from Craftsman, Weedeater,
and Shop Vac.7 The authors reported that 3 ft from the leaf blower, the SPLs ranged from 80 to
96 dBA, with an average value of 88 dBA, and concluded that leaf blower noise did not violate
the OSHA permissible noise exposure limit. Given an average of 88 dBA and high of 96 dBA,
however, it is more likely that at least two or three of the leaf blowers were measured at above 85
dB& the Cal/OSHA action level for a hearing conservation program. At least one &the leaf
blowers had an SPL above the Permissible Exposure Limit of 90; at 96 dBA, the operator would
7ARB was not able to obtain the specific models tested or actual SPLs for each model leaf
blower.
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be restricted to a 3 hr, 29 minute daily exposure without hearing protection. These results suggest
that operators are probably exposed to noise levels above the Cal/OSHA action levels or
permissible exposure limits.
In the absence of additional empirical data, noise exposures for operators can be estimated
based on manufacturer-provided data on SPLs at 50 fl from the blower by applying the rule that
each halving of the distance increases the sound pressure level by six decibels. It is reasonable to
assume that the distance from the backpack blower to the operator’s ear is between nine and 18
inches, and three feet is a good approximation &the distance from the operator’s ear to the noise
source for a hand held unit. Using this relationship, we calculate that an operator using a
backpack leaf blower with a reported 75 dBA level at 50 t~ would be exposed to maximum sound
levels of 105 to 111 dBA. These exposure levels would restrict the operator without hearing
protection to daily use of one-half to one hour. See Table 7 for additional examples:
Table 6. Sound Levels Exposures for Operator
Sound Level At 3.125 ft At 1.56 ft At 0.78 ft
at 50 ft, dBA (37.5 in),(18-19 in),(9 in),
dBA dBA dBA
65 89 9_5 101
70 94 100 106
75 99 105 111
Finally, the Echo Power Blower Operator’s Manual advises operators to wear hearing
protection whenever the unit is used. The user is instructed that "OSHA requires the use of
hearing protection if this unit is used 2 hours per day or more." This statement indicates that the
operator would be exposed to an SPL of 100 dBA or more during use.
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3.3.7 Use of Hearing Protection
No study was found that documented the incidence of heating protection usage among
operators of leaf blowers. Heating protectors are widely available, and some manufacturers
provide an inexpensive foam ear plug set with the purchase. More expensive custom molded ear
plugs and ear muffs provide better protection than the moldable foam ear plugs, but again no data
were available on usage. Two studies did examine the incidence of usage of hearing protection in
other industries. In one study of 524 industrial workers, although 80.5% were provided with
hearing protection devices, only 5.1% wore them regularly (Maisarah & Said 1993). In another
study of metal assembly workers who worked in a plant where the average noise level was 89
dBA, only 39% of the men reported wearing hearing protection always or almost always (Talbott,
et al. 1990).
3.3.8 Summary of Noise Emissions
While millions of Californians are likely exposed to noise from leaf blowers as bystanders,
given the ubiquitousness of their use and the increasing density of California cities and towns,
there is presently no way of knowing for certain how many are actually exposed, given the lack of
studies. In contrast, it is likely that approximately 60,000 lawn and garden workers, are daily
exposed to the noise from leaf blowers. While anyone operating a leaf blower for more than 1-2
hrs daily should be using hearing protection, it is unlikely that even half of those exposed to noise
over 100 dBA are protecting their heating. Gardeners and landscapers, however, are very aware
that noise is a problem, but perhaps they see it more as a hinderance to their ability to do their
work, given that at least 100 cities in California ban or restrict the use of leaf blowers. Thus,
purchases of quieter leaf blowers, based on manufacturer data, are increasing. Unfortunately,
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many models intended for the do-it-yourself homeowner are not as quiet as the commerical
backpack models, and models targeted for the homeowner market usually do not advertise their
noise rating.
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4.0 REVIEW OF HEALTH EFFECTS
Leaf’blower noise, exhaust and fugitive dust emissions, as discussed in previous sections
of this report, are health concerns. Following is a discussion of health effects of particulate matter,
carbon monoxide, unburned fuel, and noise. Particulate matter, carbon monoxide, and unburned
fuel are part of exhaust emissions; particulate matter is also the major component of fugitive dust.
Ozone is a pollutant that is formed in the atmosphere through chemical reactions of hydrocarbons
(unburned fuel) and nitrogen oxides in the presence of ultraviolet light. Although not directly
emitted, ozone is a pollutant of concern because leaf blowers emit hydrocarbons, which react to
form ozone. The health effects of nitrogen oxides are not discussed as emissions from leaf blowers
are relatively low, and any health effects would be negligible.
National Ambient Air Quality Standards have been set by the federal government to
protect public health and welfare. In addition, California has State ambient air quality standards.
These standards include a margin of safety to protect the population from adverse effects of
pollutant exposure. The National Ambient Air Quality Standards and California standards are
intended to protect certain sensitive and probable risk groups of the general population (Appendix
C).
4.1 Particulate Matter Health Effects
Airborne PM is not a single pollutant, but rather is a mixture of many subclasses of
pollutants with each containing many different chemical species OA.S. EPA 1996). Particles of 10
microns ~m) and smaller are inhalable and abl~ to deposit and remain on airway surfaces. The
smaller particles (2.5 ~m or less) are able to penetrate deep into the lungs and move into
intercellular spaces. The respirable particles owe their negative health impacts in part because of
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their long residence time in the lung, allowing chemicals time to interact with body tissues. ARB
staff could not locate data on the specific chemical and physical make-up of leaf blower dust, thus
only generic effects from the respirable fraction (particles 10/2m and smaller) are addressed.
Many epidemiologic studies have shown statistically significant associations of ambient
PM levels with a variety of negative human health endpoints, including mortality, hospital
admissions, respiratory symptoms and illness measured in community surveys, and changes in
pulmonary mechanical function. Associations of both short-term, usually days, and long-term,
usually years, PM exposure with most of these endpoints have been consistently observed. Thus,
the public health community has a great deal of confidence in the conclusions of the many studies
that PM is significantly associated with negative health outcomes.
There remains uncertainty, however, regarding the magnitude and variability of risk
estimates for PM; the ability to attribute observed health effects to specific PM constituents; the
time intervals over which PM health effects are manifested; the extent to which findings in one
location can be generalized to other locations; and the nature and magnitude of the overall public
health risk imposed by ambient PM exposure. While the existing epidemiology data provide
support for the associations mentioned above, understanding of underlying biologic mechanisms is
incomplete (U.S. EPA 1996)
4.2 Carbon Monoxide Health Effects
Carbon monoxide (CO) is a colorless, tasteless, odorless, and nonirritating gas that is a
product of incomplete combustion of carbon-containing fuels. With exposure to CO, subtle health
effects can begin to occur, and exposure to very high levels can result in death. The public health
significance of CO in the air largely results from CO being absorbed readily from the lungs into
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the bloodstream, forming a slowlyreversible complex with hemoglobin, known as
carboxyhemoglobin. The presence of significant levels of carboxyhemoglobin in the blood reduces
availability of oxygen to body tissues (U.S. EPA 1999c).
Symptoms of acute CO poisoning cover a wide range depending on severity of exposure,
from headache, dizziness, weakness, and nausea, to vomiting, disorientation, confusion, collapse,
coma and at very high concentrations, death. At lower doses, central nevous system effects, such
as decreases in hand-eye coordination and in attention or vigilance in healthy individuals have
been noted (Horvath et al. 1971, Fodor and Winneki 1972, Putz et al. 1976, 1979, as cited in U.S.
EPA 1999c). These neurological effects can develop up to three weeks after exposure and can be
especially serious in children.
National Ambient Air Quality Standards have been set to protect public health and welfare
(see Appendix C for a listing) and are intended to protect certain sensitive and probable risk
groups of the general population. The sensitive and probable risk groups for CO include anemics,
the elderly, pregnant women, fetuses, young infants, and those suffering from certain blood,
cardiovascular, or respiratory diseases. People currently thought to be at greatest risk from
exposure to ambient CO levels are those with ischemic heart disease who have stable exercise-
induced angina pectoris (cardiac chest pain) (ARB 1992a, U.S. EPA 1999c).
4.3 Unburned Fuel Health Effects
Some toxic compounds are present in gasoline and are emitted to the air when gasoline
evaporates or passes through the engine as unburned fuel. Benzene, for example, is a component
of gasoline. Benzene is a human carcinogen and central nervous system depressent (ARB 1997b).
The major sources of benzene emissions in the atmosphere are from both unburned and burned
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gasoline. The amount of benzene in gasoline has been reduced in recent years through the
mandated use of California Reformulated Gasoline (ARB undated fact sheet, on the Internet at:
http://arbis.arb.ca.gov/cbg/pub/cbgbkgrl .htm). Other toxic compounds that are emitted from
vehicle exhaust incluce formaldehyde, acetaldehyde, and 1,3-butadiene. Acetaldehyde is a
probable human carcinogen (Group B2) and acute exposures lead to eye, skin, and respiratory
tract irritation (ARB 1997b). 1,3-Butadiene is also classified as a probable human carcinogen, is
mildly irritating to the eyes and mucous membranes, and can cause neurological effects at very
high levels (ARB 199To). Formaldehyde is highly irritating to the eyes and respiratory tract and
can induce or exacerbate asthma. It is also classified as a probable human carcinogen (Group B1)
(ARB 1997b). As with benzene, emissions of these toxic air contaminats from gasoline exhaust
have been reduced by the use of California Reformulated Gasoline.
4.4 Ozone Health Effects
Ozone is a colorless, odorless gas and is the chief component of urban smog. It is by far
the state’s most persistent and widespread air quality problem. Ozone is formed from the chemical
reactions of hydrocarbons and nitrogen dioxide in the presence of sunlight. Leaf blowers emit
substantial quantities of hydrocarbons, .primarily from unburned fuel, which can react to form
ozone. Ozone is a strong irritant and short-term exposures over an hour or two can cause
constriction of the airways, coughing, sore throat, and shormess of breath. Ozone exposure may
aggravate or worsen exisitng respiratory diseases, such as emphysema, bronchitis, and astham.
Chronic exposure to ozone can damage deep portions of the lung even after symptoms, such as
coughing, disappear. Over time, permanent damage can occur in the lung, leading to reduced lung
capacity.
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4.5 Noise Health Effects
The literature on health effects &noise is extensive. In this section of the report, staff
have relied heavily on the reports by the U.S. EPA (1974, 1978, 1979, 1981a), the National
Institutes of Health Consens Statement (NIH 1990), a review article by Alice Surer (1991), an
edited book on the biological effects of noise (Prasher and Luxon 1998), and Karl Kryter’s
handbook of noise (1994), in addition to original research articles.
In summary, exposure of adults to excessive noise results in noise-induced heating loss
that shows a dose-response relationship between its incidence, the intensity of exposure, and
duration of exposure; and noise-induced stimulation of the autonomic nervous system, which
reportedly results in high blood pressure and cardiovascular disease (AAP 1997). In addition there
are psychological effects. The following subsections will first discuss noise-induced heating loss,
followed by impacts on the fetus and newborn, then physiological stress-related effects. Finally,
we will discuss impacts on sleep, communication, effects of performance and behavior,
annoyance, and effects on wildlife and farm animals. These are not perfect divisions between
discreet affects: sleep-deprivation, for example, can lead to stress, elevated blood pressure, and
behavioral changes; psychological effects lead to physiological changes, especially if the
annoyance is repeated and uncontrollable. But first, before discussing effects, the reader should
have an understanding of how the ear functions.
4.4.1 Hearing and the Ear
A detailed discussion of the ear’s anatomy and the mechanism by which we hear is beyond
the scope of this report, but a basic level of understanding is necessary so that later discussions of
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damage to hearing will be better understood. For further information, the reader is referred to any
basic acoustics or biology text.
The ears are paired sensory organs that serve two functions, to detect sound and to
maintain equilibrium; only sound detection will be addressed in this report. The ears are composed
of the external ear, middle ear, and the inner ear. With the assistance of the external ear in
collecting and focusing sound, vibrations are transmitted to the middle ear via the ear canal and
the eardrum. The vibrations of the eardrum are transmitted by the bones of the middle ear to the
fluid-filled sensory organof the inner ear, the cochlea. As the fluid of the inner ear vibrates, the
hair cells located in the cochlea bend, stimulating sensory receptors, and leading to nerve impulses
being transmitted to the brain via the auditory nerve. The greater the hair cell displacement, the
more sensory receptors and neurons are stimulated, resulting in the perception of an increase
sound intensity.
Hearing loss can result from damage or growths in any portion of the ear and the part of
the brain that processes the nerve impulses. Damage to the outer and middle ear result in
"conductive" heating loss, in which case the vibrations could still be perceived and processed if
they can be transmitted by another means to the inner ear. Damage to the inner ear and auditory
¯ nerve result in "sensorineural" heating loss. Sensorineural heating loss can be temporary, if the
body’s mechanisms can repair the damage, but cumulative inner ear damage will result in
permanent hearing loss. Aging, diseases, certain medications, and noise cause the majority of
sensorineural hearing loss, which is not reversible by surgery or medication, and is only partially
helped by hearing aids.
4.4.2 Noise-Induced Hearing Loss
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Roughly 25% of all Americans aged 65 and older suffer from heating loss. Contrary to
common belief, heating loss is not part of the natural aging process, but is caused by preventable,
noise-induced wear and tear on the auditory system (Clark and Bohne 1999). Noise-induced
hearing loss develops gradually over years and results from damage to the inner ear. Sensory cells
within the cochlea are killed by exposure to excessive noise. These cells do not regenerate but are
replaced with scar tissue. After weeks to years of excessive noise, the damage progresses to the
point where hearing loss occurs in the high-frequency range and is detectible audiometrically;
speech comprehension is not usually affected and so at this level hearing loss is usually not
noticed by the individual. Finally, with continued exposure, the heating loss spreads to the lower
pitches necessary to understand speech. At this point, the impairment has proceeded to the level
of a handicap and is quite noticeable. The damage, however, is not reversible and is only poorly
compensated for by heating aids.
There is considerable variability among individuals in susceptibility to heating loss. Based
on major field studies conducted in the late 1960s and early 1970s, the U.S. EPA suggested that a
24-hour equivalent sound level of 70 dBA would protect 96% of the population, with a slight
margin of safety, from a heating loss of less than five dBA at 4000 Hz (U.S. EPA 1974). This 24-
hour, year-round equivalent sound level is based on a forty-year work-place noise level exposure
(250 working days per year) of 73 dBA for eight hours and 60 dBA for the remaining 16 hours.
The National Institute for Occupational Safety and Health reviewed the recommended
occupational noise standard more recently (NIOSH 1996) and reaffirmed its recommended
exposure limit of 85 dBA for occupational noise exposure. The report concluded that the excess
risk of developing occupational noise-induced hearing loss for a 40-hr lifetime exposure at 85
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dBA is 8%. In comparison, the OSHA regulation [29 CFR §1910.95] allowing a 90 dBA
permissible exposure limit results in a 25% excess risk of developing hearing loss. The OSHA
regulation, however, has not been changed to reflect the recommendation of the National Institute
for Occupational Safety and Health.
NIOSH also recommended changing the exchange rate, which is the increment of decibels
that requires the halving or doubling of exposure time, from the OSHA mandated 5 dBA to 3
dBA. This would mean that if the worker was permitted to be exposed to 85 dBA unprotected for
8 hr, then a noise exposul;e level of 88 dBA would be limited to 4 hr per day. The 3-dBA
exchange rate is supported by acoustics theory, and by national and intemational consensus.
OSHA, however, continues to mandate the 5 dBA exchange rate in its regulations.
4.4.3 Effects on the Fetus and Newborn
The human cochlea and peripheral sensory end organs, which make up the ear, complete
their normal development by 24 weeks of gestation (AAP 1997). The sense of hearing matures
from that point as the nervous system matures. Sound transmits well through the watery
environment of the uterus, and thus the fetus is exposed to noise throughout the second half of its
development. Studies have found that exposure to excessive noise during pregnancy, such as
received when the mother’s occupation exposes her to noise, may result in .high-frequency hearing
loss in newborns, and may also be associated with prematurity and low birth weight. For
newborns, studies have found that exposure to noise in the Neonatal Intensive Care Unit may
result in damage to the cochlea, and thus heating loss, and may disrupt normal growth and
development of premature infants.
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The American Academy of Pediatrics (1997) recommends further research to conclusively
determine health effects of noise exposure on pregnant women and their fetuses and infants.
Pediatricians are encouraged to screen infants for noise-induce hearing loss when their mothers
are occupied in jobs that require the wearing of protective hearing devices. The Academy asks the
National Institute of Occupational Safety and Health to conduct research on noise exposure
during pregnancy and recommends that the OSHA consider pregnancy when setting occupational
noise standards.
4.4.4 Non-Auditory Pliysiologieal Response
In addition to hearing loss, other physiologic and .psychologic responses resulting from
noise have been noted and are termed "non-auditory" effects. Noise is assumed to act as a non-
specific biological stressor, eliciting a "fight or flight" response that prepares the body for action
(Suter 1991). Noise could, therefore, cause multiple changes in the body’s autonomic nervous
system and influence behavior. Research has, therefore, focusedon effects of noise on blood
pressure and changes in blood chemistry indicative of stress. Despite decades of research,
however, the data on effects are inconclusive. While many studies have shown a positive
correlation between hearing loss, as a surrogate for noise exposure, and high blood pressure,
many have shown no correlation (Surer 1991; Kryter 1994).
Problems with conducting studies of the health of people working in noisy industries
include the difficulty of controlling for variables that may also be correlated with the effect one is
trying to correlate with noise exposure. Kryter (1994) highlights psychological variables that will
also stimulate the autonomic nervous system. These include work conditions in a noisy industry,
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which may be inherently unsafe, raising stress levels. In addition, the noise itself may interfere
with the ability to carry out work, thus increasing a worker’s anxiety about work performance.
Suter (1991) concludes her review of the evidence with the statement that "[m]ost effects
appear to be transitory, but with continued ~xposure some effects have been shown to be chro~fic
in laboratory animals. Probably the strongest evidence lies in the cardiovascular effects. However,
many studies show adverse effects, while many other show no significant differences between
expefimen*~a; ~-~ ....’~ ne ~auonm msmmes Ior occupauonal batety an~i
Health (1996) has called for further research to define a dose-response relationship between noise
and non-auditory effects, such as hypertension and psychological stress.
4.4.5 Interference with Communication
The inability to communicate can degrade the quality of living directly, by disturbing social
and work-related activities, and indirectly, by causing annoyance and stress. The U.S. EPA
(1974), in developing its environmental noise levels, determined that prolonged interference with
speech was inconsistent with public health and welfare. Noise that interfers with speech can cause
effects ranging from slight irritation to a serious safety hazard (Surer 1991), and has been shown
to reduce academic performance in children in noisy schools, as reviewed by Kryter (1994). The
U.S. EPA (1994), therefore, developed recommended noise levels which are aimed at preventing
interference with speech and reduced academic performance. An outdoor yearly average day-
night sound level of55 dBA permits adequate speech communication at about 9-10 if, and also
assures that outdoor noise levels will not cause indoor levels to exceed the recommended level of
45 dBA.
4.4.6 Interference with Sleep
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It is common experience that sound rouses sleepers. Noise that occurs when one is trying
to sleep not only results in repeated awakenings and an inadequate amount of sleep, but is also
annoying and can increase stress. Noise that is below the level that awakens, however, also
changes the sleep cycle, reduces the amount of"rapid eye movement" sleep, increases body
movements, causes cardiovascular responses, and can cause mood changes and performance
decreases the next day (Suter 1991). The U.S. EPA’s indoor average yearly day-night level of 45
dBA, which translates into a night time average sound level of 35 dBA, is thought to protect most
people from sleep disturbance.
An average sound level, however, does not adequately account for peak sound events that
can awaken and disturb sleep. Continuous noise has a significantly smaller sleep disturbance effect
than intermittent noise. Research has found that subjects in sleep laboratory experiments will
gradually reduce the number of awakeni-ngs throughout the night in response to noise, but other
physiological changes, including a momentary increase in heart rate, indicative of arousal do not
change. The question is whether physiological arousal, short of awakening, has a negative health
effect. While study results are inconclusive on this issue, it is clear that noise above a certain level,
about 55 dBA L~q, according to Klyter, 1994, will awaken people, even after long periods of
repeated exposures. Repeated awakenings reduce feelings of restedness and cause feelings of
annoyance, leading to stress responses and associated health disorders.
4.4.7 Effects on Performance and Behavior
The working hypothesis in this area has been that noise can cause adverse effects on task
performance and behavior at work, in both occupational and non-occupational settings. Results of
studies, however, have not always been as predicted. Sometimes noise actually improves
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performance, and sometimes there are no measurable differences in performance between noisy
and quiet conditions (Surer 1991). Kryter (1994) concluded that masking by noise of other
auditory signals is the only inherent auditory variable responsible for observed effects of noise on
mental and psychomotor tasks.
A frequently-cited study comprising two experiments examined "helping behavior" in the
presence and absence of noise. Mathews and Canon (1975) tested the hypothesis that high noise
levels may lead to inattention to the social cues that structure and guide interpersonal behavior. In
a laboratory study in which subjects did not know they were being studied, they found that fewer
persons were willing to help someone who had "accidentally" dropped materials when
background noise levels were 85 dB thah when they were 65 dB or 48 dB. In a subsequent field
study, similar results were demonstrated with background noise from a lawn mower. Initially,
subjects were tested as to their willingness to help a man who had dropped books and .papers
while walking from his car to a house; in this test, helping behavior was low both in ambient (50
dB) and high (87 dB) noise conditions. When the test was repeated with a cast on the arm of the
man who dropped the books, helping behavior was high under ambient noise (80%) and low
under high noise (15%) conditions. These and other studies lead to the conclusion (Surer 1991)
that even moderate noise levels can increase anxiety, decrease the incidence of helping behavior,
and incrc, ase Ilae likeS~od afhastile heAaav~or.
4.4.8 Annoyance and Community Response
Annoyance is measured as an individual response to survey questions on various
environmental factors, such as noise (Suter 1991). The consequences of noise-induced annoyance
are privately held dissatisfaction, publicly expressed com~plaints, andpossibly adverse health
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effects. Various U.S. govemment agencies began investigating the relationships between aircraft
noise and its effect on people in the early 1950’s. On reviewing studies to date, the U.S. EPA
concluded that there was no evidence of public complaints-if the average yearly day-night sound
level was less than 50 dB CLI.S. EPA 1974).
Fidelt et al. (1991) reveiwed and synthesized the relationship between transportation noise
and the prevalence of annoyance in communities based on over 30 studies. The relationship is an
exponentially increasing function, with less than 10% of respondents reporting themselves to be
highly annoyed at noises Under an average day-night sound level of 56 dB. Fifty percent
responded they were highly annoyed at sound levels approaching 79 dB, and nearly every person
was highly annoyed at sound levels above 90 dB. Based on over 450 data points, the best-fit
equation for the quadratic function was found to be:
% highly annoyed = 0.036L~-~ -- 3.2645L~ + 78.9181.
Suter (1991 ) concluded that throughout decades of study, community annoyance has been
positively correlated with noise exposure level, and that although variables such as ambient noise
level, time of day, time of year; location, and socioeconomic status are important, the most
important variable is the attitude of the affected residents. Kryter (1994) further elaborates that
interference by noise, and the associated annoyance, depends on the activity of an individual when
the noise event occurs, and the intensity and duration of the noise. People have different beliefs
about noise, which are also important. Those most annoyed share similar beliefs that the noise
may be dangerous, is probably preventable, are aware that non-auditory effects are associated
with the noise source, state they are sensitive to noise, and believe that the economic benefit
represented by the source is not important for the community (Fields 1990).
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4.4.9 Effects of Noise on Animals
Kryter (1994) reviewed studies on the effects of noise both on wildlife and farm animals.
None of these studies examine noise-induced heating loss, but rather looked at effectsof noise on
litter size, prevalence of wildlife, and milk production. Most of the studies were conducted to
examine the effects of airport noise, including noise from landings and takeoffs and sonic booms ¯
near commercial and military airports, and noise from construction activities during laying of
pipelines across wilderness areas. Negative impacts on wildlife and farm animals, due to noise,
were not supported by the studies. In the airport studies, the absence of human activities in the
areas surrounding the high noise exposure zones appeared to be more important than noise,
resulting in abundant wildlife. Farm animals exposed to frequent sonic booms showed little or no
negative effects, again using such criteria as reproduction, milk production, and growth rate.
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5.0 POTENTIAL HEALTH AND ENVIRONMENTAL
IMPACTS OF LEAF BLOWERS
Leaf-blower operators and bystanders have two different types of exposures to exhaust
and fugitive dust emissions: exposures that occur on a regional basis and exposures that occur
when one is within a short distance of the leaf blower. Regional exposures are those exposures to
air pollution that occur as a result of leaf blowers contributing to the basin-wide inventory of
ozone, carbon monoxide, particulates, and toxic air pollutants. While leaf blowers contribute a
small percentage to the air basin-wide air pollution, they are nonetheless a source of air pollution
that can be, and is, controlled through exhaust emission standards, as detailed in section 3.1.3.
The second type of exposure is of greater concern. Lawn and landscape contractors,
homeowners using a leaf blower, and those in the immediate vicinity of a leaf blower during and
shortly after operation, are exposed to potentially high exhaust, fugitive dust, and noise emissions
from leaf blowers on a routine basis. The ARB staff have not located much data on how often,
how long and at what concentrations these exposures occur. The ARB off-road model assumes
that each commercial leaf blower is used for 275 hr/yr, and each residential leaf blower is used for
10 hr/yr, which does not address the annual use of leaf blowers by the operator.
A consumer products manufacturer (Anon. 1999), who asked to remain anonymous for
this report, recently surveyed 100 lawn and landscape contractors in the Southern California area.
The survey found that the average use of commercially-owned leaf blowers by operators was
three hours per day. Assuming a five day work-week, then, the average commercial gardener,
then, would use a leaf blower for 780 hours per year. No similar data were collected for
homeowners doing their own work, however. As staff do not expect homeowners to possess
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more than one leaf blower at a time, unlike commercial gardeners who many own more than one
leaf blower to ensure that they always have one available for work, the ARB estimate of 10 hr/yr
usage per leaf blower is probably close to the annual operator exposure.
Because of the highly speculative nature of the data on operator and bystander exposure
time, staff have been unable to develop estimates of the quantifies of chemicals individuals could
be exposed toper amount of time. Instead, impacts are presented somewhat qualitatively, with
recommendations for appropriate personal protection or controls from hazards that staff have
found to be significant. SO that the reader can better picture the magnitude Of different impacts for
exhaust and fugitive dust emissions, staff have estimated the amount of still air the emissions from
ten minutes of leaf blower operation would have to be mixed in to prevent a local, transitory
exceedance of the relevant national ambient air quality standards. The PM standards, however, are
not generally short term exposure standards, but have been selected as the best surrogate for short
term exposure standards. The following estimates for exhaust and fugitive dust exposures, then,
have no objective significance, in and of themselves, but are presented for comparative purposes.
5.1 The Worker
In this section, data on impacts are presented thatapply to the commercial leaf blower
operator, which is a person who regularly uses the leaf blower in the course of a landscaping or
gardening job. Staff assume that a commercial leaf blower operator will use equipment with a
higher horsepower than a residential, or hdmeowner, operator, and that most of the work will
consist of operating the leaf blower in areas where the silt loading values are high.
5.1.1 Exhaust Emissions
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The "typical" leafblower owned and operated by commercial lawn and landscape
contractors, with an average horsepower of three and a load factor of 50%, will produce the
emissions for a ten minute usage as shown in Table 7. Ten minutes is considered to be a
reasonable estimate of the time it might take to clean an average yard. If’the actual usage is
greater or less than ten minutes, the data presented in Table 7 can be adjusted accordingly.
Table 7. Leaf Blower Emissions and Mixing Space for the Operator,
3 hp average and 50% load factor, 1999
. Exhaust Ten min. of Exhaust Amount of Mixing
Emissions Emissions Space Necessary-to Not
Exceed the NAAQS
Hydrocarbons 199.25 g/hr 33.21 g NA9
Carbon Monoxide 423.54 g/hr 70.59 g 1777 m3
Particulate Matter 6.42 g/hr 1.07 g 7133 m3
Fugitive Dust ---102 g 680,000 m3
For CO, the 70.59 g emitted in ten minutes would require mixing in 1777 m3 air in order
not to exceed the NAAQS 1 hr standard for CO of 35 ppm, assuming that all of the CO remains
in the immediate area, and that the person being exposed breathes this air for 1 hour. The amount
of air in 1777 m3 is comparable to the amount of air that would fill a cube 12.1 m, or 39.7 ft, on
each side. As discussed above, this estimate does not permit a determination of the health impacts
of the exposure to CO. These data, however, do suggest that the relatively large amount of CO
emitted directly into the air space surrounding the operator could result in the inhalation of an
SNational Ambient Air Quality Standard
9No relevant NAAQS exists for "hydrocarbons" as this is a catch-all category for many
chemicals.
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unhealthful dose. Staff recommends that further research is warranted to determine exposures and
related health impacts from small, two-stroke engine emissions.
For the PM10 that is directly emitted from exhaust emissions, the air space necessary for
mixing in order not to exceed the 24-hour standard for PM10 is larger than that for CO,
comprising an amount of air equivalent to a cube 19.2 m, or 63.2 ft, on each side. PM emissions
from the blown dust, however, dwarf the PM emissions from exhaust.
5.1.2 Fugitive Dust
For fugitive dust,ten minutes of use during commercial use would exposure the operator
to significant amounts of PM (Table 7). A cube of air 88 m, or 288.4 ft, on each side would be
equivalent to the 680,000 m3 of air that would be needed to dilute the PM10 sufficiently to avoid
exceeding the 24-hour national ambient air quality standard. While leaf blower operators would
not be expected to spend significant amounts of time within such a particulate cloud, the day-in-
day-out exposure to this much PM10 could have serious health consequences in the long-term
Short-term exposures of one to two days to high levels of PM can lead to coughing and minor
throat irritation. Long-term exposures have shown statistically significant associations of ambient
PM levels with a variety of negative human health outcomes, as discussed previously. These data
strongly suggest that professional leaf blowers operators, and those regularly working within the
envelope described above, should wear a face mask effective at filtering PM from the air.
5.1.3 Noise
The potential health impacts of leaf blowers on workers from noise center on noise-
induced heating loss. Two factors contribute to hearing loss in typical career gardeners: the high
sound pressure levels emitted by leaf blowers at the level oft he operator’s ear, and the infrequent
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use of hearing protection. While we cannot calculate the percentage of workers who will
experience noise-induced hearing loss without additional data, these two factors are likely
responsible for hearing loss in a high percentage of workers, although they may not notice any
hearing loss until many years have passed. Although no studies exist documenting hearing
protection usage in gardeners, usage is low in other industries and there is no reason to assume
gardeners behave differently. In addition to heating loss experienced by the worker, pregnant
women operating leaf blowers put their fetuses at risk of developing hearing loss, and noise
exposure may also lead to low birth weight and prematurity from the in-uterus exposure. No
hearing protection program has been devised for the fetus.
In order to reduce hearing loss, employers should require that employees use hearing
protection. State and local health and enforcement agencies should promote heating protection in
campaigns targeted at professional landscapers and gardeners. Hearing loss is gradual, and may
become obvious only years after the .exposure has ceased. While gardeners may feel they are
somehow immune to hearing loss, which is a typical attitude of young, healthy workers, staff has
concluded that noise-induced hearing loss is a certainty for the majority of professional leaf
blower operators.
5.2 The Public-at-Large
Those who are not worldng in landscaping and gardening fall into two categories:
homeowners doing their own gardening and bystanders. Homeowners who chose to use a leaf
blower likely experience relatively low-level exl~osures which they conlrol. Bystanders may
experience low or high exposures, depending on the nature of the exposure. Bystanders, however,
almost never have chosen to be exposed to the exhaust, dust, and noise emissions of the leaf
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blower. Thus their attitude toward the leaf blower is likely very negative and they may be highly
annoyed by the exposure. In addition, staff have received letters from some people, and read
testimonials on Internet web-sites, concerning acute symptoms, such as asthma and allergies,
exhibited by sensitive individuals to relatively limited exposures. These symptoms have not been
evaluated in this report as they are anecdotal and unable to be substantiated. It is important,
nevertheless, to acknowledge that some individuals may be very sensitive to the emissions from
leaf blowers and unable to tolerate exposures that do not seem to bother other individuals.
In addition to homeowner-leaf blower operators and bystanders who are in the vicinity of
leaf blower operation, everyone is exposed to a small degree to air pollution that results from
exhaust and dust emissions from leaf blowers. This report does not quantify those exposures, but
the ARB does regulate exhaust emissions from leaf blowers, as from most other sources of air
pollution. As discussed elsewhere, all sources of air pollution need to be reduced in order that
Californians can breath clean air.
5.2.1 Exhaust Emissions
The "typical" leafblowerowned and operated by a homeowner for private residential use
is assumed to have an average horsepower of 0.8 and a load factor of 50%, based on the ARB
off-road emissions model. Using the same methods as above produces the emissions shown in
Table 8.
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Table 8. Leaf Blower Emissions and Mixing Space for the Homeowner,
0.8 hp average and 50% load factor, 1999
Exhaust Ten min. of Exhaust Amount of Mixing
Emissions Emissions Space Necessary to Not
Exceed the NAAQS1°
Hydrocarbons 56.7 g/hr 9.45 g NAt~
Carbon Monoxide 119.2 g/hr 19.86 g 500 m3
Particulate Matter 1.44 g/hr 0.24 g 1,600 m3
Fugitive Dust --1.8 g 12,000 m3
For comparison, for CO the mixing space necessary to avoid exceeding the standards is
equivalent to a cube of air 8 m, or 26 ft, on each side. For all emissions, exposures are
considerably lower in a residential setting than in a commercial setting. The data presented in
Table 8 do not address bystander exposures, for which we have even less data than for leaf blower
operators, and again it is not possible to determine health impacts.
5.2.2 Fugitive Dust Emissions
For fugitive dust (Table 8), 1.8 g of PM10 emitted in ten minutes would need to be mixed
in a volume of 12,000 m3 of air in order to avoid exceeding the 24-hour standard for PM10. This
is an amount &air equivalent to a cube 22.9 m, or 75.1 ft, on each side. As with the commercial
exposure, this is a potentially hazardous exposure, but because the homeowner is likely using leaf
blowers for a very short time each week, the concern is much lower than for commercial
~°National Ambient Air Quality Standard
X~No relevant NAAQS exists for "hydrocarbons" as this is a.catch-all category for many
chemicals.
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gardeners. Still, staff would recommend that even homeowners wear a dust filtering mask when
using a leaf blower.
5.2.3 Noise
The homeowner who uses a leaf blower for a brief amount of time each week or two is
unlikely to experience noise-induced hearing loss. The cummulative exposure to many
recreational sources of noise, however, is likely to great enough to impact heating (Clark 1991).
Those who regularly use noisy power equipment should be in the habit of using heating
protection.
The likelihood of a bystander exposed to leaf blower noise on an irregular basis
experiencing hearing loss is low. The potential health impacts from leaf blowers on bystanders
that are likely more important include interefence with communication, sleep interuption, and
annoyance. Each of these impacts may in turn lead to stress responses, although research has not
conclusively tied chronic exposures with any particular adverse health outcome. Although
interference with communication, sleep interuption, and annoyance may not seem to be serious
impacts, they are important quality of life issues for many people. At least 100 municipalities in
California have restricted or banned the use of leaf blowers within city limits in response to people
who obj ect to the loud noise of leaf blowers interupting their lives.
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6.0 SUGGESTED FUTURE RESEARCH
6.1 Exhaust Emissions
The ARB has an active research program to determine exhaust emissions from engines
that it regulates. Existing and future exhaust emission control standards will continue to require
that manufacturers reduce emissions from the small off-road engines found in leaf blowers. Staff
conducts periodic reviews of technology to determine whether further emission reductions are
possible. For example, the ARB has recently awarded a contract to the Southwest P~esearch
Institute to conduct research entitled "Particulate Emissions from Marine Outboard Engines,
Personal Watercraft and Small Off-l~oad Equipment." The objectives relevant to leaf blower
technology are (1) to measure the emissions from two-stroke engines used in small off-road
equipment, with an emphasis on PM emissions and polycyclic aromatic hydrocarbon levels; and
(2) to determine particle size distribution and mutagenic toxicity of.the PM. The contractor will
obtain and test five engines typically used in leaf blowers or similar off-road equipment, and staff
have recommended that engines used in leaf blowers be among those chosen.
In addition to this study, staff has identified investigation into small off-road engine
deterioration as an area for future research; engine deterioration causes emissions to increase with
engine usage. In general, annual usage data, both for the leaf blower equipment and for the
operator, would be helpful. As discovered during the course of this report, data on the annual
usage of the equipment may not correlate well with how long an operator, commercial or
residential, uses the equipment throughout the year.
6.2 Fugitive Dust
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ARB staff found a fundamental lack of information on the nature and quantity of fugitive
dust blown, or resuspended, by leaf blowers. AeroVironment attempted to calculate the amount
of fugitive dust resuspended by leaf blowers in the SCAQMD as a first order approximation.
Empirical data are needed, however, as calculations only go so far. Any study would need to
consider a large number of variables, such as substrate, humidity, time of year, and type of
materials being moved by the leaf blower. Ideally, as part of a future research project, one would
want to first quantify the emissions in actual use by:
(1) inventorying the typesof surfaces cleaned by leaf blowers statewide, and by air district,
(2) determining the silt loading for surfaces that are cleaned, and
(3) performing source testing to determine the amount of PM30, PM10 and PM2.5 entrained in
the air, and to determine the "exposure envelope" associated with leaf blower usage.
This info, mmficm.could then_b~.u.sed.~o calculate _mo~~~ ~f d,,st zss~i~terl .~_h
leaf blower usage.
In addition to quantifying emissions, it would also be important to determine what is in the
dust. This information, however, would not apply only to leaf blowers, but would reflect what is
in dust that is resuspended by wind from any source. Presently, chemical speciation data are
available for sources such as paved and unpaved roadways. For leaf blowers, we should also
examine the make-up of dust from lawns, sidewalks, parking lots, and flower beds. In addition to
chemical speciation, it would also be useful to analyze the dust for the presence of herbicides,
pesticides, bacterial endotoxins, and other toxins.
6.3 Noise Emissions
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The investigation and reduction of noise emissions is not part of the ARB’s authority or
mission, although noise was investigated by the ARB at the requestion, through SCR 19, of the
California Legislature. Traditionally, noise control and abatement has been a local function,
although a state Office of Noise Control did exist for a short time; the Office was housed within
the Department of Health Services. The following suggestions for noise related research, then, are
offered with comment as to the appropriate agency for carrying out the research.
Quantifying noise exposure might be appropriate for the ARB to conduct only as a part of
a larger effort that would be aimed at better understanding the number of leaf blowers, their hours
of use, and differentiation between residential and commercial use. In addition, the Office of
Environmental Health Hazard Assessment may be able to assist with preparing a noise exposure
report, just as they have prepared reports on exposures to toxic air contaminants. Otherwise, each
suggested research item is more appropriately conducted by the Department of Health Services
Occupational Health Branch or a state of federal agency dedicated to worker issues.
(1) Quantification of the number of Califomians affected by noise and noise exposure levels.
The purposes of this study would be two-fold: First, to assess the number of workers who are
exposed to leaf blower noise, the number of hours they are exposed daily, and their daily noise
dose and exposures. Second, to determine the number of people exposed non-occupationally to
leaf blower noise, average noise exposures, frequency of exposure (e.g., daily, weekly), and how
they are affected (e.g., annoyed, interference with sleep or communication).
Agencies potentially responsible: ARB; Office of Environmental Health Hazard Assessment;
California Department of Health Services Occupational Health Branch.
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(2) Evaluation of hearing loss in gardeners, with emphasis on those who use leaf blowers as a
part of their work. The purpose of this study would be to evaluate, more specifically, the
incidence of noise-induced hearing loss in occupationally exposed gardeners. Non-occupational
exposure to noise would also need to be assessed.
Agencies potentially responsible: National Institutes for Occupational Safety and Health;
California Department of Health Services Occupational Health Branch.
(3) Incidence of use of personal protective equipment by gardeners. The purpose would be to
determine the frequency Of use and types used of personal protective equipment (PPE) such as
heating protectors, dust "comfort" masks, and eye protection. This study should be conducted
with an education component, with the goal of increasing the use of PPE.
Agencies potentiaH responsible: California Occupational Safety and Health Administration;
California Department of Health Services Occupational Health Branch.
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7.0 FUTURE LEAF BLOWER TECHNOLOGIES
7.1 Engine Technologies That Reduce Exhaust Emissions
For the most part manufacturers have met the 1995-1999 emissions standards by
calibrating their engines to use less fuel, and improving production practices to include tighter
tolerances. With implementation of more stringent standards in the 2000 model year will come
more advanced techno!ogies. Various manufacturers have indicated that they will meet the 2000
model-year standards with either small four-stroke engines that have been specifically designed for
light-weight and multi-pOsitional use, two-~stroke engines with direct fuel injection, or two-stroke
engines with stratified scavenging. Moreover, virtually all manufacturers have indicated that they
will provide complying products, though not all have been specific about the technologies they
plan to use. The various technologies represent a variety of ideas, but ultimately all would reduce
the amount of fuel delivered to the combustion chamber. The technologies are briefly described
below.
7.1.1 Four-Stroke Engines
Four-stroke engines possess the advantage that the exhaust stroke expels very little
unburned fuel, so engine-out HC emissions are much lower than a two-stroke engine. This is
because exhausting the spent gases and refilling the cylinder with a fresh air/fuel charge happens
sequentially in a four-stroke engine, but simultaneously in a two-stroke engine. In the past,
four-stroke engines have not been able to operate multi-positionally, because of engine lubrication
problems, so four-strokes have not traditionally been used in handheld equipment. Ryobi and
Honda, however, are two companies that have developed handheld four-stroke engines for the
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2000 standards. Honda has indicated that it intends to use its engine in blowers and Ryobi offers
attachments that can convert a string trimmer to a blower.
7.1.2 Fuel-Injected Two-Stroke Engines
Fuel injection provides better control of the amount and the timing of fuel entering the
cylinder. By limiting the fuel admitted to the amount necessary for combustion, and timing fuel
introduction to limit the fuel exiting with the exhaust gases, less unburned fuel exits the engine.
The loss of unburned fuel is the primary cause of the high HC emissions from two-stroke engines;
up to one third of the fuel going into a conventional two-stroke engine exits the exhaust pipe
unburned. Tanaka is a company that has developed a fuel-injected two-stroke engine, partially
through funding provided by the ARB’s Innovative Clean Air Technologies program.
7.1.3 Stratified Scavenging Two-Stroke Engines
Stratified scavenging refers to a system that prevents mixing of the incoming fuel with the
exhaust gas by injecting a layer ("strata") of air between the two. The result is that less of the
fresh (unburned) fuel escapes, and HC emissions are dramatically reduced. Test results indicate
that the technology can easily meet the 2000 standard. As put into practice by Komatsu Zenoah,
manufacturer of the Red Max line of blowers, the stratified scavenging engine retains all the
advantages of a conventional two-stroke: light-weight, high power output, and relatively simple
design. The result is an engine that operates nearer to the chemically balanced air/fuel ratio, which
also translates into improved fuel economy.
7.1.4 Two-Stroke Engine with Compression Wave Technology
This technology involves a compressed-air-assisted fuel injection system that eliminates
the unburned fuel during the scavenging process of the exhaust poison of the two-stroke cycle.
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Engines utilizing this technology retain much of the conventional two-stroke design and hardware,
and although the fuel metering system needs to be designed toperform with the engine’s needs, it
reportedly does not need to provide high precision in timing or in spray quality.
The thrust behind the technology is a compression wave, which causes the fuel and air in
the cylinder to be Neatly disturbed, in effect functioning as a shock wave. This atomizes the fuel
~and mix,e,s it more.thoroughly with the air. In .addition, the ~:ompression wave helps keep fuel from
sticking to the cylinder. According to the U.S. EPA regulatory impact analysis for its small engine
regulatoq efforts (EPA 1-999a), the system as developed by John D.eere Consumer Products
includes an "accumulator" which collects and temporarily stores compressed air scavenged from
the crankcase. The piston compresses the air in the crankcase on the piston’s downward stroke.
The fuel injection system uses the piston head to open and close its ports. With respect to engine
power, John Deere Consumer Products states that the en, ginepower remains nearly the same as
the engine without the technology. The technology is planned for production on John Deere
Consumer Products equipment in California in 2000.
7.1.5 Two-Stroke Engines with Catalysts
In addition to the above technologies, some manufacturers currently offer equipment with
catalytic converters; in fact, the presence of a catalyst is sometimes used as a marketing feature in
Europe. As with an automobile, the catalyst assists the conversion of hydrocarbons and carbon
monoxide to more benign compounds.
7.2 Sound Reduction Technologies
Leaf blower manufacturers are developing new designs to both reduce the amount of noise
from leaf blowers and change the quality of sound to make it less irritating (L. Will, Echo, pers.
DRAFT: DO NOT CITE OR QUOTE 73 15 September 1999
comm.). The methods range from quieting the engine noise by insulating the engine compartment
to changing the design of the fan. Significant sound comes from the fan itself, and thus new fan
designs have the potential to change both the loudness and sound quality.
Electric leaf blowers are usually significantly quieter than gasoline-powered leaf blowers
because of the absence of the engine noise. The Los Angeles City Council requested that its
Department of Water and Power develop a quieter leaf blower, and a contract was awarded to
AeroVironment. The finn developed a prototype electric, battery-powered blower that should be
produced in small quantities for testing late in 1999 or early in 2000 (L. Johnson, LADWP, pers.
comm). This blower is discussed more in section 7.4 below.
7.3 Methanol
The use of methanol as a fuel for leaf blowers came about following ordinances to ban the
use of "gas-powered" leaf blowers. Some parties have undertaken the development of
methanol-fueled leaf blowers as an alternative. However, no manufacturer has yet certified a
methanol blower, nor has any manufacturer indicated plans to do so in the near future, thus
methanol-fueled leaf blowers operate in violation of California and federal lawl If methanol
engines were to be offered, they would need to comply with the same emissions standards as
gasoline engines. The use of methanol also raises some concerns beyond those associated with a
gasoline-fueled intemal combustion engine. These include flame luminosity, as methanol bums
with a pale flame, leading to safety issues, and toxicity.
7.4 Electric Equipment
Another technology in current use, particularly for residential applications, is powering the
leaf blower with electricity. Electric equipment tends to be less expensive than the equivalent
D1LA_FT: DO NOT CITE OR QUOTE 74 15 September 1999
gasoline-powered equipment, with comparable performance on residential products. Staff
investigated the products available at several mass market stores, and found that corded electric
blowers are available. Additionally, AeroVironment, working under the auspices of the Los
Angeles Department of Water and Power, has developed a.prototype battery-powered blower for
commercial use. As many as 1500 pre-production models will be distributed to various gardeners
and landscapers to verify its utility for commercial use (L. Johnson, LADWP, pers. com.).
7.5 Alternatives to Leaf Blowers
Questions have been asked about the impacts of other methods of street cleaning, such as
using a broom or washing down the street with water. No data could be located to permit an
estimation of fugitive dust emissions due to using broom. An assessment of the amount of water
that would be used in lieu of leaf blowers falls outside of the scope of work for this report. Data
on whether or not these alternatives are louder or quieter than leaf blowers seem contradictory
and many require an expanded study to verify.
D1LAFI’: DO NOT CITE OR QUOTE 75 15 September 1999
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