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Recent Study Finds HEPA Filters Reduce Particle Pollution by 60%

2011 June 29

A recent study conducted by Dr. Ryan Allen of Simon Fraser University and colleagues demonstrated that using portable high-efficiency particle air (HEPA) filters can reduce the presence of air particles by about 60%. This in turn resulted in decreased presence of some cardiovascular risk factors leading the researchers to conclude that filters would help reduce cardiovascular morbidity due to wood smoke. [Allen RW, et al. An air filter intervention study of endothelial function among healthy adults in a woodsmoke-impacted community. Am J Respir Crit Care Med. doi:10.1164/rccm.201010-1572OC]

This may help communities mitigate immediate indoor air health concerns. We hope to have two focused webinars on health effects related to wood smoke within the next few months. Please let us know if you have suggestions or requests for the webinars. Also, if you know of other recent health studies, please include the link as a comment. Thanks!


Dr. Allen’s Presentation to the BC American Lung Association-

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2 Responses leave one →
  1. Alan Smith permalink
    July 9, 2011

    I can understand why HEPA filers would reduce particulates in a static situation but I found that with smoke infiltrating the house, even with the windows closed, from a chimney five yards away, three home HEPA units and a huge industrial unit achieved very little. There must be several million North Americans in the same situation where smoke enters the home faster than fliters can remove it.
    Alan Smith Albera Chapter Canadian Clean Air Alliance


  2. July 22, 2011

    Accepting comments is good ! It looks like the openness of the Obama administration is bearing fruit in the environmental area. I love the EPA finally moving to enforce the intent of the clean air act to make large sources keep pm2.5 below 35 mcg/m3, 24 hr ave instead of the pm10 std of 150 mcg/m3 which was allowing 130+/- mcg/m3 pm2.5 in many cases and causing threats to ife, health, safety, welfare.

    RE: Hepa filters. My experience with hepa filters with wood smoke from whole house heating is like Alan’s above. I tried 2 hepa filters that did not touch the pollution at all. Then one advanced filter that did a little and only on my third attempt with a hyper hepa filter from IQ Air with a gas filter did I get some cleaning and that was with a reduced smoke load, not whole house heating.

    I had to tape some windows, not all, 3 out of 11 in rooms and 1 out of 5 in the basement along with caulking sills to get some control and I am an engineer by education. Few will be able to control wood smoke infiltrating houses with a hepa filter and it is a burden people should not have to take on.

    The EPA has written that wood smoke smells indicate a problem. I assume a health problem, but you are not clear. Please include the word health as health nuisances must be enforced but common nuisances do not have to be enforced. This will help millions of wood smoke victims.

    I love the EPA’s statements that wood smoke is 12 times more carcinogenic than tobacco smoke. Tobacco smoke has no safe level according to the Surgeon General. By logic, is it true that there is no safe level of wood smoke? Or is the safe level: 180 mcg/m3,hrs per the Wildfire Smoke website with the CDC? Or is 35 mcg/m3 for 24 hours the safe dose per ambiant pm2.5 stds?

    Wood smoke smells and some visible smoke engulfing cities have been photographed and reported commonly. The CDC says if you see or smell wood smoke there is a health problem and the governments all have to protect life and health. So why is the USA allowing this negligance to go on and not ammending law per the constitution to enforce the intent of the clean air act to prevent air pollution problems any where, not just at regional monitors?


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