Chainsaw vs. Auto Emissions

[jteneyck]

Chainsaws and other unregulated two-stroke engines put out a tremendous amount of pollution for their size.  In one day's use a mid-sized saw puts out about as much pollution as a mid-sized car does driven across the country.  I had heard this statement many years ago, but to see if it was true I checked EPA’s website where I found the emission data in blue in the tables attached below.  The new, Phase 2 regulations for chainsaws require cutting the HC (hydrocarbon) emissions to less than half the Phase 1 regs.  However, the mandated overall reduction is only 12% due to the unchanged requirement of the dominate CO emissions.  Keep in mind that these are maximum permissible values, and saws in either category would likely be lower leaving the factory.  Next I used the power (KW) of a Stihl MS 361 for the Phase 1 regulations and a Stihl MS 362 for the Phase 2 regulations to calculate how many total grams of pollution could be emitted over a good working day of 6 hours.  Because the 362 has slightly higher power the reduction in total emissions might only be 10% over the MS 361.  Anyway, I compared this with a car driven 3000 miles, as shown in the second table, both the Federal regulations and the more advanced ULEV regulations which many cars now meet.  As you can see, a saw having the power of a MS-361 and meeting the Phase 1 regulations puts out just about the same total emissions in 6 hours as a car meeting the Fed. Regs. driven 3000 miles.  And both saws could put out about twice as much as an ULEV car.  There aren't nearly as many saws as cars, but you get the idea.  More importantly to me personally is that you are standing right there breathing in some of that pollution, some components of which, like benzene, are carcinogenic
 
I first thought there would be a larger reduction for the Phase 2 regulations, but then I realized that the CO emissions aren’t likely to go down unless you use a catalytic converter.  The HC reduction of over 50% is good since we’ll be breathing fewer nasties, but the overall reduction of 10% hardly seems worth the effort required by the saw makers and resultant cost.  And if you change the factory settings and richen the mixture any improvement is probably minimal, maybe even lost completely. 

Stihl claims a 70% reduction in emissions for the MS 362 “compared to previous models”, but don’t specify which models.  Probably true compared to “Phase 0” regulations, and could be true compared to the MS 361 but I’d like to see the data.  Stihl also claims a 20% reduction in fuel consumption, which would help as you can see in the last line of the top table.   

Overall, I’m not impressed by the regulations and suspect the EPA isn’t either and that further reductions will be implemented in the next few years.  Those regulations could lead to the development of electronic control of carburetion, which would be a real benefit, and may also require the addition of a catalytic converter to the 2-cycle motor and/or development of a 4-cycle motor.  Catalytic converters have been evaluated in development saws in Europe, and 4-cycle motors already are available in weed whackers and similar implements although they don’t yet have the price/performance required to be effective in a chainsaw. One thing for sure is that change is constant.  There always will be problems when new technology is introduced but, over the long haul, safety, performance, and now emissions, will improve. 


                        

[Rocky_J]

It's comparable to reducing the water level in the ocean using an eye dropper. How much comparable 'pollution' is generated by firing up my bbq grill for a couple hours?   

[Warbird]

Not as much as the gas I expel after a few beers.

[Al_Smith]

If you mixed a few pickled eggs with that beer it's likely you could  generate enough gas to fuel that grill . Not to mention raising the level of the Atlantic with well placed beer residue faster than it could be lowered with an eye dropper .

Oh I'm bad I really have to take this pollution stuff more seriously .

[Stutz]

If you want to talk about logging by helicopter, I would not worry about the few pollutants that a chainsaw puts into the atmosphere when the helicopter is putting out 10,000x more per log.
I wonder how cost effectively saw makers can introduce direct injection.
I bet used and abused 361’s will develop a cult following where they get rebuilt over and over.

[RSteiner]

What happens when you factor in the loss of the forest canopy with it's ability to filter out the nasties from emissions??    The chainsaw becomes a monster to the environment.

In the grand scheme of things I would think that more emissions are generated by lawn mowers used to keep golf courses looking good than chainsaws.  And, what about the emissions and other nasties created by the power companies for the electricity generated to recharge golf cart batteries?   

I would dare to say there are more golf carts in use for more hours per year than chainsaws.

The bottom line is it is going to cost the consumer more.

Randy

[567paloggger]

what about the big rig trucks and tri axles with all the smoke and why are they worrying about use so much what about the other countrys they dont care at all i guess its time to buy as many chainsaws new to keep them on the side

[bandmiller2]

Pretty much a phart in a hurricane,gov just wants their grubby hands on and more control.Frank C.

[windthrown]

OK, for the OP, get an electric chainsaw. That's the one for you. No nasty pollution generated by the saw anywhere near you, its all pushed environmentally friendly downwind to the coal fired electric factory. If you are cutting in the woods, get an electric generator and move it safely away from where you are falling those 4 inch DBH 'monsters'. Make sure you buy the most fuel efficient and enviromentally safe generator. And be sure to leave as many trees as you can to suck up all the Co2 that you are generating. Carbon sequestering is important to save us from overheating this planet (until Himalayan Mountain errosion puts us into another ice age, that is).

Or better yet, get a hand saw.

[jteneyck]

All diesel trucks, including heavy duty ones - i.e. 18 wheelers, are now regulated as well.  As the old ones are replaced you will see, and smell, less soot and pollution from those once belching behemoths.  Lawnmowers are or soon will be on the list as well.  Big powerplants are going to be on the hit list too.  A whole bunch of new coal plants recently were put on hold because of pending legislation.  Those are truly where much of the problem comes from along with cars/trucks so, personally, I hope regulations are implemented.  Just like cars, power plant emissions will implement controls once it's required, the technology exists, and the cost to do so will be small for the consumer.  Regulations in other countries are hit or miss; however, many EU coutries have regulations about equal to ours.  So far, things that use jet fuel seem to be unregulated, so helicopters can continue to belch a while longer. 

The point for me really isn't about the global environment as far as chainsaws are concerned.  It's about the environment right around me when I'm using the thing.  A lot of people died of asbestosis until it was regulated and finally abolished, a couple of my friends included.  Sometimes regulations are good, and they always create opportunities for inventive people which we Americans used to be.   

[Al_Smith]

Everybody has a right to an opinion and I honor that . However were I so inclined to be averse to the possibilities of pollution  from an  automobile or chainsaw I would ride a bike or horse and use a handsaw .Simple as that .

Well maybe not a horse if you subscribe to Al Gores ideas of grazing animals . Something I doubt seriously he thought up all on his own even  after he invented the internet .

Now does common sense prevail here ?An automible will use at least  two gallons of fuel per hour providing it's about the size of a pregnant rollerskate .A 70 cc chainsaw will just barely use that much in a day and a long one at that .How in the world then could a saws use per day equal driving coast to coast in even a puddle jumper 

[jteneyck]

Now does common sense prevail here ?An automible will use at least  two gallons of fuel per hour providing it's about the size of a pregnant rollerskate .A 70 cc chainsaw will just barely use that much in a day and a long one at that .How in the world then could a saws use per day equal driving coast to coast in even a puddle jumper 

Cars are four stroke machines, have electronic fuel injection, oxygen sensors to control air/fuel mixture, and the all important catalytic converter to control emissions.  A chainsaw has none of those.  The data is correct.  Despite it's small size and low fuel consumption compared to a car, chainsaws put out as much or more emissions.  As a point of reference, cars today put out 99+% less pollution than those prior to the advent of catalytic converters.  That's why cars have less pollution than a chainsaw.   

[DouginUtah]

I guess we have a problem in that pollution and emissions have not been defined.

A car driving across America will put out about 2000 lbs. of CO₂. A chainsaw will put out about 40 lbs. of CO₂ per day. So, if we are talking just about CO₂ there is no question that the car is a much greater polluter. Granted, there are many other emissions and pollutants--I am only addressing the CO₂ emissions.

Catalytic converters do not reduce CO₂ emissions. 

[TimRB]

"The point for me really isn't about the global environment as far as chainsaws are concerned.  It's about the environment right around me when I'm using the thing."

In that case, then, it would be more to the point to see if loggers and other chainsaw users show increased rates of respiratory or other ailments because of their proximity to the saws.  Since 2-cycle chainsaws as we know them today have been around for what, 70-80 years (I'm guessing) and users don't seem to be dropping like flies, maybe the pollution numbers are a red herring. 

Tim

[Al_Smith]

 
"The point for me really isn't about the global environment as far as chainsaws are concerned.  It's about the environment right around me when I'm using the thing."
  I ask is this an argument simply for the sake of argument or is there a point to this . Again I would point out were I so anal about a 2 cycle saw engine I would avoid them like the plague .

It's not like everyone in the world runs them every day you know so what exactly is the point in question ? What next ,outlaw bar-b-que grills ?

[jteneyck]

I guess we have a problem in that pollution and emissions have not been defined.

A car driving across America will put out about 2000 lbs. of CO2. A chainsaw will put out about 40 lbs. of CO2 per day. So, if we are talking just about CO2 there is no question that the car is a much greater polluter. Granted, there are many other emissions and pollutants--I am only addressing the CO2 emissions.

Catalytic converters do not reduce CO2 emissions.

Regulated emissions for cars are broadly defined by EPA, and other world regulatory agencies, as hydrocarbons (HC), carbon monoxide (CO), and nitrous oxides (NOx).  The regulated amounts are shown in the table I attached to my first post.  Note it is CO, carbon monoxide, not CO2, carbon dioxide.  Modern catalytic converters oxidize CO to CO2 through a complex reaction that simultaneously reduces NOx to N (nitrogen).  So of course a car outputs CO2, that's what the converter is designed to do.  This isn't a good thing, but it's far better than emitting CO.  The only way to reduce CO2 emissions is to reduce fuel consumption.  

In that case, then, it would be more to the point to see if loggers and other chainsaw users show increased rates of respiratory or other ailments because of their proximity to the saws.  Since 2-cycle chainsaws as we know them today have been around for what, 70-80 years (I'm guessing) and users don't seem to be dropping like flies, maybe the pollution numbers are a red herring.

 

Good point.  I'll look into it and see if I can find any data.  

[jteneyck]

I ask is this an argument simply for the sake of argument or is there a point to this . Again I would point out were I so anal about a 2 cycle saw engine I would avoid them like the plague .

It's not like everyone in the world runs them every day you know so what exactly is the point in question ? What next ,outlaw bar-b-que grills ?

From an EPA document, open to the public to read:

Health and Environmental Benefits
The Phase 2 handheld engine standards will result in a 70 percent reduction in HC+NOx emissions from these engines beyond the 32 percent reduction expected from the Phase 1 standards. This is equivalent to an annual reduction of 500,000 tons of exhaust HC+NOx emissions by the year 2027. This reduction in HC+NOx emissions will be accompanied by an overall reduction in fuel consumption.

Small SI engines currently produce approximately one tenth of U.S. mobile source HC emissions and are the largest single contributor to nonroad HC inventories. Thus, the Phase 2 standards will help the States in their progress towards compliance with the NAAQS for ozone.

Both HC and NOx contribute to the formation of tropospheric ozone through a complex series of reactions. In a recent report, researchers emphasize that both HC and NOx controls are needed in most areas of the United States. EPA's primary reason for controlling emissions from small SI handheld engines is the role of their HC emissions in forming ozone. Of the major air pollutants for which National Ambient Air Quality Standards have been designated under the Clean Air Act, the most widespread problem continues to be ozone, which is the most important component of smog.

Like it or not, chainsaws are major polluters.  We all use them because of their benefit.  I'm not going to start cutting my wood by hand, but I am interested in seeing improvements made to reduce emissions from them. 

[Warbird]

Sometimes regulations are good, and they always create opportunities for inventive people which we Americans used to be.  

Hi jteneyck.  Depends on who is doing the regulating, don't you think?  I do not trust our government to leave well enough alone.  Next thing you know, they will be wanting to regulate the gas *I* expel after drinking a couple of beers and eating some of those pickled eggs Al mentioned.  And they will want to charge me a lot of $$$ for the courtesy!  No thanks.

I am well aware of the dangers from using my chainsaw and I don't need it regulated any further.  If someone wants to invent a 'safer' or 'greener' chainsaw, go for it.  But don't do it with my money or get the government involved because of some folk's personal prejudices about workplace safety.

I can also make a good argument on how effective "regulations" actually end up being but will leave that for a future post.  Oh, and "we Americans" would be a whole lot more inventive, prosperous, and productive if it weren't for the out of control regulations we already have from the fine folks at agencies like the EPA. 

[RSteiner]

The point for me really isn't about the global environment as far as chainsaws are concerned.  It's about the environment right around me when I'm using the thing.  A lot of people died of asbestosis until it was regulated and finally abolished, a couple of my friends included.  Sometimes regulations are good, and they always create opportunities for inventive people which we Americans used to be.   

A solution for personal protection might be a self contained breathing system similar to what is used by fire fighters.  Something like that would protect the user from harmful emissions.   However, this should in no way be a mandatory piece of equipment only an option for those who desire added protection.

Randy

[Al_Smith]

Forgetting about those nasty chainsaws for just a moment and taking into the politics of polution might be interesting . Did you know that industries are taxed on the amount of polution they emit ? I have no doubt this tarrif is used to fund tthe EPA and like organizations .It would therefore in my pea sized mind seem to me the EPA is kind of funding it's on coffers and feathering their own nests .

Not mind you I am in favor of out and out  polution of our air and streams it's just that I for one take most data these wizards evangelise about with a grain of salt. In other words I trust them about as far as I could throw them .

Now take for example freon 12 which is the best refridgerant ever known .Fact is it was so good they outlawed it .All that did was sell new refrigeration units because the old ones lasted way too long .Lawnmowers --the old ones could be tuned ,the new ones can be recycled into a bumper for a Toyota .And on and on and on .