SAN FRANCISCO (CBS SF) – The exhaust and ear-splitting sounds of gas-powered leaf blowers are set to become a thing of the past at San Francisco city parks, as the blowers will soon be replaced by electric ones.

According to the city’s Recreation and Park Department, blowers with two-stroke engines will be phased out starting in August for models that run on battery packs. The process is expected to take 18 months.

“Phasing out two-stroke, gas-powered blowers, along with the greenhouse gasses and smog compounds they release, is an important and proactive step we can take for the health of our planet and our park users,” said Phil Ginsburg, the department’s general manager.

Officials said the gas-powered blowers emit “particularly high emissions” of carbon monoxide, nitrous oxides, and hydrocarbons due to the engine, which requires fuel to be mixed with oil. According to a fact sheet from the California Air Resources Board (.pdf), one hour of leaf blower use emits as much smog-forming pollution as driving a 2017 Toyota Camry about 1,100 miles, or the distance from Los Angeles to Denver.

“Battery powered blowers reduce noise to non-damaging levels and do not release the toxic exhaust emissions of two stroke cycle gas-powered blowers,” officials said.

Park officials said currently about 20% of the department’s leaf blowers are electric.