Leaf blowers have become increasingly affordable and popular in the past 20 years. California completed a survey in 20121 that indicated about 13% of households there have one. A 2015 study using national emission inventory estimates2 indicates there are almost 11 million gasoline leaf blowers in the US.
Soon after their introduction in the early 1970's, leaf blowers were considered a noise nuisance and were banned in two California cities. Since then, many other cities, including some in New York State, have adopted ordinances restricting their usage. In 2000, the California legislature requested that the California Air Resource Board (CARB) prepare and submit a report summarizing the potential health and environmental impacts and to include recommendations for alternatives. CARB found that human health can be impacted from noise, fuel and exhaust emissions, and dust.
Loud noise may cause hearing loss. When leaf blowers were first introduced, the noise from them averaged 78 decibels (dB) but measured at a distance of 50 feet away. While more modern leaf blowers are available with ratings of 65 dB or lower at 50 feet, many that are on the market still exceed 70 dB at 50 ft. A leaf blower rated at 70 dB at 50 feet may generate noise levels over 105 dB at the operator's ears. For comparison purposes, the table below shows some decibel levels of every day sounds at normal distances.
A decibel level from 60 to 70 represents a 10 times increase in loudness.
Fuel (evaporative and unburnt) and exhaust emissions consist of hydrocarbons (HC), oxides of nitrogen (NOx), carbon monoxide (CO), and fine particulate matter (PM). Emissions from gas powered leaf blowers are substantial. The amount of CO (carbon monoxide) emitted from a typical backpack leaf blower for just 1 hour is equal to CO coming from the tailpipe of a current year automobile operating for over 8 hours. For the other pollutants, the amounts are even greater.
More information is available in the March 2016 document "Nonroad Spark-Ignition Engines 19 Kilowatts and Below: Exhaust Emission Standards" available through the EPA link in the right hand column.
Leaf blowers push 300 to 700 cubic feet of air per minute at 150 to 280 MPH. The resulting dust can contain PM2.5 and PM10 particles including pollen and mold, animal feces, heavy metals, and chemicals from herbicides and pesticides. Dust emissions from leaf blowers are not part of the USEPA inventory of fugitive dust sources. No data on the amount and size distributions of dust from leaf blower activities have been collected, although estimates for PM10 range from <1% up to 5% of the total generated statewide.
- Use a mulching mower and stay off paved areas.
- Rake or sweep leaves, and compost or use for landscaping.
- Use an electric plug-in or battery operated yard vacuum. Many shred the leaves, so they are compacted and can be used as compost. Vacuums are also effective with needles.
- Use a battery operated or plug-in leaf blower. Electric blowers are generally quieter than gasoline models and do not generate ground-level exhaust emissions.
- If electric power is not available, consider an EPA approved 4-stroke internal combustion engine instead of a 2-stroke.
- Ensure the equipment is in proper working order - inspect the air filters, air intakes and muffler before operation.
- Operate the blower at the lowest possible throttle speed to do the job. Lower speeds reduce sound and give the operator maximum control. Full throttle is seldom necessary.
- Use the nozzle extension so the air stream is directed close to the ground to minimize dust. Pay close attention to the generation of dust. In dusty conditions, use mister attachments to slightly dampen surfaces.
- To clean an excessively dusty area, use a shovel to pick up the large debris.
- Don't use leaf blowers to move large debris piles.
1 California Air Resources Board, "2012 California Survey of Residential Lawn and Garden Equipment Owners: Population and Activity". Accessed April 29, 2016. Available at http://www.arb.ca.gov/msei/2012_residential_lawn_and_garden_survey_v5_public.pdf.
2 Jamie Banks and Robert McConnell, "National Emissions from Lawn and Garden Equipment". Accessed April 29, 2016. Available at https://www.epa.gov/sites/production/files/2015-09/documents/banks.pdf.