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  • Writer's pictureWorld Half Full

Petrol leaf blowers are on the nose


For more than 100 million years, trees have dropped their leaves, creating a protective layer that provides cover for snails, bees, and butterflies. Decaying leaves fertilised the soil and gave nutrients back to the trees. Today, fallen leaves still provide a harvest festival of benefits — unless they get blasted into oblivion with a leaf blower.

Across the United States, some 11 million leaf blowers roar into action every year, obliterating delicate debris with 320 kmh winds. Their distinctive, whining drone is hard to escape. But restrictions on leaf blowers have been spreading across the country, permitting some locales to experience life as nature intended, at a humane decibel level.

Outright bans on the petrol-powered machines have recently taken effect in Washington, D.C.; Miami Beach, Florida; and Evanston, Illinois. California will end the sale of petrol-powered blowers next northern summer. Their hum will also be silenced in Portland, Oregon and Seattle, Washington in the coming years. Unless people let their lawns remain scattered with leaves, rakes and battery-powered devices will slowly replace them.

Long the dream of noise-sensitive people everywhere, bans began taking off after the lockdowns in 2020 forced office workers home. Stuck in their neighbourhoods all day, people discovered the beauty of birdsong, along with a newfound loathing for the whine of the leaf blower.

Communities that had tried and failed to get restrictions on the devices are now beginning to see success, says Jamie Banks, co-founder and president of Quiet Communities, a not-for-profit dedicated to reducing noise pollution. “There’s a lot more consensus around doing something about it,” he notes. Today, more than 200 towns across the United States have restrictions on leaf blowers, though many just put limits on what hours or times of year people can use them.

The bans are also being fuelled by research showing leaf blowers emit a surprising amount of air pollution. The California Air Resources Board has estimated that operating a petrol-powered leaf blower for just one hour emits as much pollution as driving a standard sedan just over 1300km. How is that even possible? Well, many leaf blowers use a very inefficient two-stroke engine, which mixes oil and petrol and spits out as much as a third of that fuel as unburned aerosol. The outdated design is cheap, powerful, and very loud and dirty.

“I definitely think people underestimate the risks,” says Michael Brauer, a professor of public health at the University of British Columbia, Canada.

A study in 2015 found that lawn mowers, trimmers, leaf blowers, and other lawn equipment accounted for a quarter of all emissions of cancer-causing benzene in 2011. They also accounted for 17% of volatile organic compounds and 12% of nitrogen oxides, the primary pollutants in smog.

Petrol-powered tools also emit a shocking amount of PM2.5, fine particulate matter that’s linked to lung cancer, heart disease, dementia, and other health problems. In 2020 in the US, they released 19,776 tonnes of PM2.5, or as much as 234 million cars produce in a year, according to a report in late October.

“The big picture is that cars have gotten cleaner and cleaner and cleaner and cleaner, and this kind of equipment has not,” Brauer says. “And so this has become evident as a more important source of pollution.” Because vehicle regulations have become so strict in California, for example, small, off-road engines such as those found in leaf blowers emit more smog-producing emissions than all the 14 million passenger cars in the state.

Even their noise poses a health concern. Petrol-powered leaf blowers operate at low frequency, allowing the noise to carry over long distances and penetrate walls. “People can’t get away from the sound,” Banks says. “So you go in your house, you close your windows, you shut your doors, and you can still hear it.”

A study conducted by Banks and the US Environmental Protection Agency in 2017 found that commonly used lawn equipment was louder than the World Health Organisation’s recommended limit of 55 decibels up to 240 metres away. And every 5-decibel increase in the average daily noise level around people’s home leads to a 34% increase in heart attacks and strokes, according to Harvard research in 2020.

So why did such a dangerous device take off in the first place? The first leaf blower-like machines, invented in the late 1940s, weren’t intended to blow leaves — they were backpack crop dusters, meant for spraying pesticides. Then someone had the bright idea of removing the chemical canister so all the machine could do was blast away debris. The invention coincided with suburban growth after World War II, when having a carpet of grass around your home became part of the American dreamand the Australian dream for that matter. Fallen leaves were seen as a nuisance that needed removing; they covered up the green lawns everyone wanted to show off and turned footpaths slippery in the rain.

So in the 1970s, the Japanese company that had invented the crop duster, Kyoritsu Noki, began selling what the people wanted. Lawn care ballooned into a huge industry, and the backlash soon followed. As early as 1975, Carmel, California, banned the machines outright; by 1999, 20 cities in California had outlawed them, though it took a while for the trend to start spreading to the rest of the country.

Those bans then set off their own backlash. In 1998, a ban on leaf blowers in Los Angeles neighbourhoods sparked a protest, where gardeners — many of them recent immigrants — staged a hunger strike in front of City Hall, arguing the ban was a severe blow to their jobs. Today, the fight to save petrol-powered leaf blowers has become more organised. In May, Georgia’s governor Brian Kemp signed a law prohibiting local governments from regulating petrol-powered leaf blowers differently from battery-powered ones.

To be sure, swapping petrol for electric blowers isn’t as simple as it might sound. Landscapers have adopted a business model that allows them to go from house to house quickly — a job that can drain batteries fast, meaning some workers need to be swapping batteries out two or three times a shift. “It’s going to take more time for them to do the same job,” Banks says. “So either the customer pays for that extra time, or they relax their aesthetic expectations and say, “Okay, just do a cursory cleanup, but we can live with leaves on the ground.” And, besides, electric lawn tools still have some way to go. In California, even with all the bans on petrol-powered tools, they make up only about 6% of the equipment used by lawn care workers.

While battery-powered versions are typically cheaper than petrol ones, buying new equipment to comply with bans is expensive for landscapers. Some local governments that have adopted bans on petrol-powered blowers have also tried to help offset the costs of switching. Ahead of the 2024 ban on the sale of petrol-powered leaf blowers, California has set aside US$27 million for small landscaping businesses to buy electric equipment; Washington, D.C. has introduced a rebate program for the same purpose.

It’s worth noting that the status quo comes at a price for lawn workers, too. They’re subject to the worst of the air and noise pollution from the equipment they’re wielding. “It’s as though you’re sucking the exhaust out of the tailpipe of a car,” Brauer says. “That’s sort of what you’re doing if you’re using a leaf blower.”

It’s as though you’re sucking the exhaust out of the tailpipe of a car. That’s sort of what you’re doing if you’re using a leaf blower.

Michael Brauer


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