A Burning Question: Wood Pollution

BY ON February 1, 2012

Wood stove with burning fire inside

This is written by Appalachian Mountain Club scientist and mom, Georgia Murray and MCAF’s Yvonne Nanasi:

I grew up in a New Hampshire home with a wood furnace and fireplace. Some of my fondest memories are of gathering in the front room by the open fire, a place to get warm, toast marshmallows, and be a family. Burning wood to stay warm and provide hot water, is still a big way of life in New Hampshire and other Northern states. Wood is a plentiful and renewable resource that can be a safe and efficient fuel when burned properly. But burning wood also emits tiny particles of soot and ash, now known to harm our lungs, especially of those of our children. In fact, particle pollution is linked with increased cardiovascular problems, irritate lungs and eyes, trigger headaches and allergic reactions, and worsen respiratory diseases such as asthma, emphysema, and bronchitis.

In winter-time, this type of air pollution can be significant when wood burning is combined with a cold winter night inversion in valley communities, like Keene, NH, resulting in pollution accumulating to levels that are unhealthy by EPA standards. The NH DES recommends that if you live in a valley area, you should watch weather conditions and pay attention to Air Quality Action Day notifications.

Outdated outdoor wood boilers (OWB) have been identified as a significant source of particle pollution. Older OWB can emit more than 70 grams of particle pollution per hour. That’s nearly 10 times the EPA standard for wood stoves and 100 times what the most efficient wood stoves emit. The problem with OWB is not about the wood, it’s about the stove design. In an effort to tackle this source, New Hampshire and other New England states have embraced standards for OWB design and installation–so newly bought boilers will be cleaner.

Unfortunately, the same problems with older OWB can be true for indoor furnaces; inefficiency and improper maintenance can yield more air pollution. Yet, replacing an older furnace with a high efficiency unit can be a significant financial burden. Whatever steps a homeowner decides they can take should start with understanding some basic facts. Identifying and correcting any inefficient heating systems will help in cost and reduce pollution.

Here are some key efficiency tips:

  • Weatherization of your home is a great place to improve heating efficiency; drafts can waste 5-30% of your home heating energy, learn more about sealing/insulating and other improvement ideas
  • If using wood
    • Use well seasoned dry wood with 20% moisture burns most efficiently and results in less creosote
    • Hardwood burns the best; never burn treated wood
    • Use sustainably harvested wood to reduce your carbon footprint
    • Learn more about safe and efficient wood burning here.
  • For gas and oil furnaces following the recommended maintenance schedules will ensure proper operation, while other improvements could improve efficiency

For those who can consider changing their current home heating system here are some facts:

  • Newer EPA certified wood burning stoves – are 50% more efficient, use 1/3 less wood for the same heat, and reduce particulate pollution by up to 70%.
  • EPA ENERGY STAR qualified oil and gas furnaces are up to 15% more efficient than standard models and have highly efficient blower motors.

Eliminating home inefficient heating sources that cost you extra money and cause unwanted air pollution is one important step to assuring that New Hampshire’s children and adults breathe healthy air.

Georgia Murray is a scientist mom working to connect people and science through Mountain Watch, a citizen-science program that focuses on outdoor activities related to air quality and climate. She oversees the air and water quality science and policy work for the Appalachian Mountain Club (AMC), a non-profit organization that’s mission is to promote the protection, enjoyment, and understanding of the mountains, forests, waters, and trails of the Appalachian region. She has a Masters in Earth Science from UNH and lives with her family in Conway, NH.


Photo: Creative Commons

TOPICS: Asthma, New Hampshire, Pollution, Science

  • steve and maria

    Wa state has standards that have eliminated 99.99% of the wood boilers. Wa state laws regarding polluting from fire places are far too lax. Clean air agencies claim to enforce those lax laws. I’ve spoken with inspectors: THEY ARE WORTHLESS. Claims by wood stove makers that newer stoves pollute less are ridiculous. THEY STILL POLLUTE!! We’ re close enough to a local polluter that we smell the smoke from their wood stove and out door garbage fire. They’ve lied to the clean air agency and the local fire dept. WA state has banned 2nd hand smoke in public buildings. Why not ban 2nd wood smoke in residential neighborhoods with too many people with COPD and asthma? Steve Laiken 425-481-5077

  • CleanAirMeister

    I will agree with steve and maria: you can design the most perfect stove in the world, but it boils down the operator. My neighbor has one of these EPA stoves, and day after day, a thick, opaque cloud of smoke rolls out of his chimney. It’s like a new model car with computer-controlled emissions, if poorly-maintained, it will throw out a cloud of blue smoke!

  • Clean Air Rights for Everyone of NY

    I encourage all to get educated on the issues with wood smoke (fine particulate, VOCs, PAHS, and carcinogens) especially the thick ground level emissions from Outdoor and Indoor Wood Boilers.

    The “invention” of Outdoor and Indoor Wood Boilers (OWBs and IWBs) has been a GIANT step backwards for U.S. Air Quality because they have dampers that squash the oxygen supply to the fire so it smolders. When the damper opens putrid creosote laden smoke can be emitted for hours at a time at ground level (the smoke is so heavy it does not rise) People can be subjected to this pollution within 35 feet of their home and 365 days a year because people use these boilers year round.

    Because EPA has not done updates to New Source Performance Standards (NSPS) in over 20 years a loophole in their regulations has gone on unchecked creating major public health nuisances in the mid-west and northeast from these boilers .

    The NY Attorney General released the report, Smoke Gets in Your Lungs in 2005 and filed a petition w/the EPA. Nothing happened except they got in bed w/the Manufacturers creating a Voluntary Program misleading regulators and the public.

    Wood boilers in AG report Appendix A document emissions of up to 269 g/hr of pollution. New catalytic wood stoves are regulated and can emit no more than 4.1 g/hr. The “voluntary” program can emit up to 95 g/hr per Northeast States Coordinated Air Use Management (NESCAUM). Now the EPA is holding a webinar next week on new NSPS. Guess what. The proposal is to make the Voluntary the standard. REALLY? Nearly 25 times the pollution of wood stoves. Why the double standard. Because the lobbyists for the wood boiler manufacturers is the Heath, Patio, Barbeque Association. Check their website http://www.hpba.org and look for their NSPS initiative. Every part of Washington has been taken over by lobbyists.

    1 in 11 people have asthma in U.S. and the EPA has sold us out. I encourage people to get involved with the comment period on this backward EPA NSPS and stop the bad policy. We need science to protect our air and the EPA needs to use that science not twist testing methods to favor lobbyists.

    The EPAs 20 years of not doing their job has resulted in an estimated 500,000 wood boilers emitting 900,0000 tons of pollution. Join all of us in our fight. see http://www.rawsep.wordpress.com for updates.

  • Wood Smoke violating DHHS safe doses for wild fire smoke

    50% of New Englands pm is from wood burning per apportionment studies and census data. 10 mcg/m3 pm2.5 is from wood smoke in background pm2.5. A daily dose is 240 mcg/m3,hr. The safe dose for wildfire smoke is 180 mcg/m3,hr. This dose is associated with asthma and heart attacks in sensitives.

    EPA science on stoves is bad and unsafe because it does not compare to even ambiant pm stds and definetly not the wildfire smoke health guidelines. States say idiotic things like wood smoke is not wild fire smoke and guidelines do not have to be enforced. But the constitution guarantees rights to life and health. However, you need a lawyer to get the government to stop violating the law. EDF is right therefor to be advocating for decreasing wood burning pollution for health reasons and global warming reasons, like the U.N., But certified stoves violate the ambiant pm stds 50% of the time according to bell curves and they violate the wildfire smoke guidelines and then 180 toxic gases have to considered too like carbon monoxide and heavy metals and all the mixed ambiant pm from oil and gas combustion has to be added in. Wood smoke is abolut 4 times more toxic, so compare by multiplying wood smoke pm by 4. Then too hourly pm is 6 times 24 r pm aves.

    It is hours to heart attacks from even certified stoves, and the smell indicates health problems per EPA website writings. And it all smells too in my experience.

  • Smokeghost

    Political-commercial manipulation using the women’s vote, and it’s prohibition all over again! You guys sift through all the EPA’s epidemiology junk science, find some actual toxicology facts that relate specifically to the typical wood smoke from typical native log varieties burned throughout America and publish it. So far all that has been published is airy-fairy generalised hoo hah that involves what possibly the generalised “woodsmoke” element increasing PM readings in winter may possibly cause to human health next to an increase of wintertime hospital visits which is most likely due to an increase in dampness and mould spores inside the home. The EPA’s clean air people use a scientific method best used in the process of building a theory. Epidemiology does not build a conclusion. The accurate toxicology studies that would make the “alarming” and to some, “convincing” claims doesn’t exist. It’s too broad and too generalised. The collectivist movement with vested interest in air quality lobbying can keep saying it’s all “undeniable”, but sorry – it isn’t a belief system. It would be all a bit more convincing too if many of you weren’t preaching a ban or phase out of an already perfect form of heating and cooking technology that is already energy efficient, self sufficient, carbon neutral and renewable fuel sustainable. Focus on an outright commercial ban on cigarettes or something.

  • Nadine

    A friend of mine has a outdoor wood boiler and very little smoke comes out if it. he says its fantastic! He had something put on it to help it to smoke less. I think he said it was a clearstak device. You guys should look into it!

  • mary power giacoletti

    Wood-burning is not carbon neutral. Burning releases sequestered carbon.
    There is no such thing as a “good way” to burn wood and people who burn
    generally ignore advice anyway. The only sound advice is not to burn a
    substance which is twelve times more carcinogenic than cigarette smoke
    and forty times more biologically active.

  • steve and maria

    To smokeghost- Your reply has shown that you are as selfish and ignorant as the selfish , polluting hypocrital next door. Therefore your words are to be ignored. We can smell it, it is poison.

  • Yvonne Nanasi

    Georgia and I certainly expected to get some lively responses about OWB’s, and we share and appreciate so many of the concerns. While the EPA may not address all the issues of those who unequivocally oppose burning wood, we are gratified that the EPA jumpstarted a move towards cleaner residential stoves in 1988 by setting maximum emission standards that were what the current technology could handle. Later, some states, like New Hampshire and Washington sent a message to the EPA by setting stricter state standards. Other states, such as Montana, have implemented wood stove “changeout” programs.

    Moms Clean Air Force will continue to fight for regulations that improve these standards and advocate for our common goal – cleaner air for the health of our children. Thank you again for your comments.

    For more information, please check out: Alliance for Green Heat website: http://www.forgreenheat.org

    • CaresAboutHealth

      The only way to improve the standards is to tell people that the current ones are totally inadequate and that anyone who cares about their health or the environment should *never* buy a product that causes as much PM2.5 pollution in 10 hours (0.11 kg – tested in-service emissions) as a new car does in a year.

      If people refuse to buy an unacceptable product, manufacturers soon respond by developing acceptable ones – look at the reduction in PM2.5 emissions from diesel cars, 4WD and sports utility vehicles. Thirty years ago they emitted 0.75 grams PM2.5 per km. Now they are required to emit less than 0.005 grams – a 99.3% reduction!

  • Whole World on Your Side against Wood Smoke Pollution

    The U.N calls for the phase out of all cordwood burning in developed countries. In a way, this shows the whole world is on the side of stopping wood burning pollution. Not all wood burning, but just when it is polluting per ambiant pm stds and DHHS safe wood smoke doses and guidelines for toxic gases and toxicology studies on equivalent doses for wood smoke pm and all 180 toxic gases from wood smoke.

    EPA and DHHS studies all show the science behind the health dangers and the global warming dangers. But the politicians are making illegal laws and policies. EPA checked modeling shows the conc of pm. DHHS studies show the safe dose for wood smoke pm2.5 is about 1/4 the safe dose for pm from mixed ambiant pm2.5. Fort Collins polling on wood smoke shows 80% want enforcement of existing health nuisance laws for wood smoke. If modeling shows certified stoves cause illegal pollution, then BACT is illegal and the best designs for stoves are dangerous. Gasifier designs are the best available technology at .2 mcg/m3 not certified stoves at 16 mcg/m3, 24 hour pm which must be added to back ground pm. And if background pm is an ave 45 mcg/m3 without wood smoke, how can we allow stoves at all?

    The U.N. is right. EDF efforts have helped get progress but EDF really needs to back the consensus opinion of the world scientific and legal community.

  • CaresAboutHealth

    There is no safe level of PM2.5 and toxic PAH pollution. Adverse health effects have been detected at all levels above background.

    A review of air pollution and health by the World Health Organisation explains that PAHs “are carcinogenic by a genotoxic mode of action, their levels in air should be kept as low as possible.”

    Perhaps the best way to keep levels as low as possible is a polluter-pays tax, equal to the estimated health costs of the pollution. For cars, it would be a manageable $20 to $50 per year – a sensible policy option that might doubly benefit health by encouraging people to walk or cycle for short trips less than a couple of miles.

    But wood stoves are 100 to 1,000 times as polluting – using a new EPA-certified wood stove for just 10 hours emits as much PM2.5 pollution as the average car does in a year. Older stoves and fireplaces are even worse. Greece has learned the hard way about the massive, health-hazardous pollution caused when more than a few people use heating that is 1,000 as polluting as a car http://www.grreporter.info/en/fireplace_pollutes_air_much_1000_cars/8814

    So even if EPA stoves reduce pollution by 70% that means they are as bad as much as 300 cars, instead of 1,000. This is still not acceptable. Under a fair polluter-pays taxes, the average wood stove user would still be up for a tax of thousands of dollars per year.

    The Citizens for Environmental Health Website asks:. Why is wood smoke, a serious and deadly toxic carcinogenic neighbourhood pollutant, allowed? Because people don’t know! http://www.citizensfeh.com/sustainability_community.html This website points out that the stove manufacturers do their own testing and certification and that independent tests reported dioxin emissions were 400 times higher than claimed.

    The American Lung Association “strongly recommends using cleaner, less toxic sources of heat. Converting a wood-burning fireplace or stove to use either natural gas or propane will eliminate exposure to the dangerous toxins wood burning generates including dioxin, arsenic and formaldehyde” http://www.lungusa.org/press-room/press-releases/cleaner-alternatives-for-winter-heat.html

    The article notes the high cost of installing new heating, and the benefits of weatherising homes. If you care for your health and the environment, when replacing your heating, please follow the advice of the Americal Lung Association and don’t install a so-called EPA certified heater that will emit as much health-hazardous PM2.5 pollution in 10 hours as a car does in a year.

  • Ernest Grolimund

    Wood burning is doubling and tripling pm2.5 going into the air per Canadian census data. It should be doubling pm concentration and is but government has been hiding it till recently. New visibility reports from the weather channel and NOAA and a great new EPA approved chart in Colorado allow victims of wood smoke pollution to get the true pm2.5 background levels. IE, in NH and ME, 10 mile visibility is common on clear days in the day. This corresponds to 42 mcg/m3 pm2.5, instant concentration. It is worse at night as shown by good mobile monitoring by the state of NH. Keene, NH was monitored with peak pm2.5 at 100 mcg/m3 +/- and daily pm can be easily estimated at 50 mcg/m3, 24 hr ave. This is the truth and the official monitoring is false and fraudulent. Yes, fraudulent in the criminal sense, in my opinion. The intent of the Clean Air Act is to keep pollutants below stds “ANYWHERE” per EPA proclamations. A stove or wood furnace that the author loves, creates about 50 mcg/m3 pm2.5. Total pm2.5 is 100 mcg/m3, 24 hr ave. The wood smoke dose is 2,400 mcg/m3,hr (conc x time). The safe dose per DHHS and EPA is 180 mcg/m3,hr. Oops. There is a huge new and emerging public health problem that EDF sought to adress by challenging NSPS stds. That is good. Progress is coming to reduce pm to pellet stove level from new stoves. But choking with the damper can increase pollution commonly up to 4 times more per EPA studies or worse. And no one is comparing modeled pm to the new safe dose nor including the tox equiv of 187 air toxics. More work is needed.By ME DEP and EPA modeling, even pellet stoves pollute with 10 mcg/m3 pm2.5 and daily doses of 240 mcg/m3,hr which is more than the safe dose of 180 mcg/m3,hr. We are talking about instant platelet clumping which is the mechanism behind heart attacks. This why the Surgeon General wrote that there is no safe level of tobacco smoke and the EPA writes that wood smoke is 12 times more carcinogenic. Julie Mellums article on Wood smoke the other cigarette on the EDF website is right on.

  • Ernest Grolimund

    The EPA advises people to check visibility for background pollution. Weather Underground shows visibility commonly at 8.5 miles which converts to about 50 mcg/m3 pm2.5 by EPA approved methods developed in Colorado. The NAAQS pm std for comparison is 35 mcg/m3. This is ave pm not base pm. Base pm is about 25. Ave pm is about 50. Pm at houses near burners can be 75 or more. The intent of the Clean Air Act is to keep pollution below stds “anywhere” like at peoples houses. Clearly, the intent of the CAA is no longer working. The EPA OIG recognizes this but cannot get politicians to revises the CAA yet. 50% of the pollution is from wood burning all of a sudden by EPA and Canadian EC work.
    Pellet stoves create 7 mcg/m3 when clean and operated right. With creosote after 2 months, pm2.5 is 21 mcg/m3. With choking which is common and creosote the pm2.5 is about 63 mcg/m3. This is the good equipment. Politicians have been duped by fraud on the part of the wood burning industry and it’s lawyer lobbyists buying access with large money donations. But the depth of the problem is not known till you estimate doses of wood smoke pm2.5 and compare to the safe doses for wood smoke pm2.5 developed by the EPA and DHHS and academia and held in court. Wood smoke pm2.5 is 5 times more toxic than pm from oil and gas combustion which is historic pm. Then there is the 180 air toxics that comes with wood smoke which is present in much lower amounts in oil and gas combustion. Then the voc’s and air toxics are converted to secondary pm2.5 by sunlight in inversions which multiples pollution 20 times, as described by the Utah Air Pollution experts as happening in Salt Lake City. There a layer of visible smoke is 100 foot thick and EPA and DHHS writings on health nuisances or problems from wood smoke say that “If you see or smell wood smoke there is a health problem that has to be stopped”. But of course it is not.
    Hell and high water is resulting as described by a Clinton aide in a book with that title.
    Holy Smoke !