Summary:
- Using a modern gas leaf blower is unlikely to be equivalent to driving 16+ hours in a pickup truck.
- These claims stem from a 2011 study by car marketplace Edmunds.
- In the original 2011 study, total pollutants including CO² were not measured.
- In the 12 years since this study, much has been done to improve small engine emissions.
If you’ve read an article or two on small gas engine bans you’ve likely seen the claim that gas leaf blowers are more than 16 times more polluting than pickup trucks.
In a recent USA Today article it was put like this:
Environmentalists say using a commercial gas leaf blower for an hour produces emissions equal to driving from Denver to Los Angeles.
It was even the byline of the story by Trevor Hughes.
And this claim went out with their Twitter post of the article.
Environmentalists say using a commercial gas leaf blower for an hour produces emissions equal to driving from Denver to Los Angeles.https://t.co/FvIvHOaVtT
— USA TODAY (@USATODAY) May 1, 2023
I’m not a climate scientist or a climate reporter (just a chainsaw/small engine enthusiast), but the claim was hard to believe, so I decided to look into it. I wanted to know where it originated and why it was referenced so frequently.
But before we look at the source, here are some other examples of this claim being made.
In April 2023, The Colorado Sun published an article titled ‘Colorado could ban the sale of gas-powered mowers and blowers beginning in 2025.’
In it they share the”statistic” again: ‘One hour of running a high-polluting gas leaf blower produces emissions equal to driving a gas car 1,100 miles, or to Denver from Los Angeles.’
And they link to a December 2022 article on their site titled ‘For Colorado’s ozone, a leaf blower for 1 hour is same as 1,100 miles in a car. That’s why some urging switch to electric.’
The claim is quoted in this piece by Kirsten Schatz, a Clean Air Advocate at CoPIRG (Colorado Public Interest Research Group). She says “Running a commercial leaf blower for an hour produces even more pollution, the equivalent of an 1,100-mile car trip from Denver to Calgary” while arguing for off-road small engines to be “phased out as quickly as possible”.
At the 1:52 minute mark in this news story from CBS 8 San Diego, it’s mentioned again.
In a story on California’s ban on gas-powered lawn equipment coming into effect in 2024, the reporter states, “State officials say running a gas-powered leaf blower for one hour emits the same amount of pollution as driving from LA to Denver.”
None of those stories share the source of the claim, but there are plenty of other articles that do.
- Washington Post: How bad for the environment are gas-powered leaf blowers? (Health & Science, Sept. 13, 2013)
“In leaf blowers, two-stroke engines have been shown to emit contaminants comparable to large automobiles. A 2011 test by the car experts at Edmunds showed that “a consumer-grade leaf blower emits more pollutants than a 6,200-pound 2011 Ford F-150 SVT Raptor.”” - The New York Times: The First Thing We Do, Let’s Kill All the Leaf Blowers (Opinion, Oct. 25, 2021)
“A 2011 study by Edmunds found that a two-stroke gasoline-powered leaf blower spewed out more pollution than a 6,200-pound Ford F-150 SVT Raptor pickup truck. Jason Kavanagh, the engineering editor at Edmunds at the time, noted that “hydrocarbon emissions from a half-hour of yard work with the two-stroke leaf blower are about the same as a 3,900-mile drive from Texas to Alaska in a Raptor.”” - Sustainability WUSTL: Electric or Gas Leaf Blowers…Neither? (Community & Landscape, Nov 17, 2020)
“Surprisingly, the number of air pollutants emitted by gas-powered leaf blowers and lawn mowers exceed pollutant emissions of large automobiles, which are regulated to reduce and capture many air pollutants. A 2011 study showed that a leaf blower emits nearly 300 times the amount of air pollutants as a pickup truck.”
The 2011 study was done by an online car magazine called Inside Line (insideline.com). It was part of Edmunds, a car marketplace that helps shoppers buy the right vehicle for their needs.
See a summary of the 2011 study, ‘Leaf Blower’s Emissions Dirtier than High-Performance Pick-Up Truck’s, Says Edmunds’ InsideLine.com.’
In the study, they tested a Ford Raptor, Fiat 500, Ryobi 4-stroke leaf blower, and an ECHO 2-stroke leaf blower.
Edmunds has another article, titled ‘Emissions Test: Car vs. Truck vs. Leaf Blower’. Edmonds also put together this short video which can be found on YouTube.
And some articles link to photos from the study posted on the now-defunct Inside Line site, which were not preserved on the Internet Archive.
This study by a car website is what is so often referenced as the reason we need to get rid of lawn and garden equipment with small engines. California has a ban coming into effect, as well as many other cities or states.
While I think we can all agree that gas leaf blowers are unpleasant to be around, is the claim that using one for an hour is worse than driving over 1000 miles true?
This is the pivotal data:
| Non-Methane Hydrocarbons(NMHC) | Oxides of Nitrogen (NOx) | Carbon Monoxide (CO) | |
|---|---|---|---|
| 2011 Ford Raptor | 0.005 | 0.005 | 0.276 |
| 2012 Fiat 500 | 0.016 | 0.010 | 0.192 |
| Ryobi 4-stroke leaf blower | 0.182 | 0.031 | 3.714 |
| Echo 2-stroke leaf blower | 1.495 | 0.010 | 6.445 |
One of the big problems, pointed out by many in comments, is that total pollutants were not measured. Hydrocarbons, Nitrogen, and Carbon Monoxide levels were taken, but not Carbon Dioxide.
These are some of the comments:
- Yes, they post the numbers, but they fail to include the largest part of emissions – CO2. Also, units would be nice. 0.276 doesn’t mean anything without units.
- Would have been interesting to have normalised the results to the volume of exhaust gas emitted for each engine. The truck might have had the lowest HC but it would also have put out the greatest volume of exhaust, so actual quantity of HC for each would have been useful.
- The [Fiat] 500 throws out marginally more NMHC and NOx but a whole lot less carbon monoxide, which is way more toxic. How can you say that “overall” the Raptor is less polluting than the 500?
- Measure the airspeed from the leafblower and then rev the Ford till the exhaust airspeed reaches the leafblower speed and then measure the emissions.
- The test is seriously flawed. The majority of a car’s pollution comes at cold start when the cats and everything else on the car is cold and inefficient.
This 2011 study is still being used to justify the eradication of small engine equipment today, when there have been big improvements made to emissions.
@JETZcorp on YouTube said 11 years ago when the video was posted:
Two-strokes are superior to everything. They make massive power out of a tiny package and with relatively very few moving parts. Their emissions problem has been fixed with direct-injection, which makes them comparable to four-strokes in that category.
To which @adamnagy1439 replied in 2022:
And also the newer 2 strokes have a “3rd stroke” in which they push out the exhaust gases with normal air, not an air-fuel mixture. I would love to compare that in this test. It needs 15-20% less fuel as well.
And @JETZcorp followed up with:
It’s not a 3rd stroke. Air moves exactly the same way as before, but fuel is introduced after all the ports are closed, rather than during intake into the crankcase. That makes all the difference. A carbureted 2-stroke hedge trimmer can have worse emissions than a Lamborghini, whereas a direct-injected 2-stroke outboard often has better emissions than any of it’s 4-stroke competitors.
The point of all that is to say that small engines have improved a lot in the 12 – 13 years since this study. Chainsaws like the Stihl 500i, for example, are a completely different type of system.
There really needs to be a new study done where emissions are tested on modern cars and 2-stroke yard equipment. Rather than simply repeating the sensational claim that, in 2011, using a blower for an hour is like traveling for two days, it would be best to rely on current measurements, statistics, and studies.
One final thought from me…
What motivation did the car marketplace Edmunds have in running this study? They essentially concluded that small 2-stroke engines are exceedingly worse than large pickup trucks.
Leave your thoughts in the comments below.
