Science: What is Wrong With Opacity Reading for Wood Smoke Regulation

The question of OPACITY comes up very often in the discussion of wood smoke regulation. A reporter asked our mid-west director, Julie Mellum, what she thought about it. 12/5/2007

Denis Cuff
Contra Costa Times
from the SF Bay Area:
Hi Julie,
A few people have suggested banning wood burning altogether. This doesn't appear to be getting much traction with the air board members. They say their proposal for the year round 20 percent opacity limit on chimney smoke is adequate. What do you and your group think?

From: Julie Mellum

Subject: wood burning bans
Great article on the proposed wood burning bans in your area! Here’s what’s wrong with that picture, though: The only protection people get from wood smoke will be on the highest pollution days, and only then will burning be stopped. Everyone deserves to breathe clean air as often as possible—not just when the smog is so bad that there is no alternative but to ban the huge source of fine particulate pollution that caused elevated smog levels in the first place.
Thank you for giving me giving me a chance to say what Take Back the Air thinks about addressing wood smoke pollution.. The whole focus of my organization is to stress that the seriousness of wood smoke pollution can not be overstated!

With regard to the “opacity standard”, we don’t like it for the following reasons:

*First of all, most people seem to burn at night. Who can calculate the opacity standard when it’s dark out? Using this outmoded standard is an excuse to not address the issue.

*The “opacity” standard doesn’t address what people are ingesting into their lungs and what it’s doing to the environment when wood is burned. It’s like saying that 20% opacity from cigarettes is acceptable, so that Camel Lights are okay, but regular Camels aren’t. How can you tell if someone is smoking Camels or Camel Lights if you’re breathing their smoke?

*Officials supporting this inadequate means of evaluating the harms of wood smoke may figure that 20% opacity pollutes, but it could be worse.. According to a doctor at the Harvard School of Medicine (exact citations are readily available), there is no safe level of wood smoke. I can provide you a lot of good science if you would like it. Anyone with asthma can tell you that smoke of all kinds is a rigger for asthma attacks, and there is no safe level. Wood smoke stresses the immune systems of everyone—even healthy people..

*Regulating or even addressing opacity is extremely difficult and very subjective.

*Who determines if the opacity rate exceeds 20 per cent? And does that standard relate to one fire at a time? Or collective opacity when smoke fans out and infiltrates the area for miles around? When several fires are burning at once, to say nothing of many, the pollution goes up exponentially.

*Who goes out to check the standard if there is a complaint call. Does anyone check the standard unless someone complains? How can they determine which house the problem is coming from. It is coming from many, most of the time. And maybe it’s dark out, and you can’t see the smoke.

*Wood smoke mixes with other air pollutants and the combination can result in even more devastating and unpredictable health effects: such as the
London Smog Incident of 1956” or 1957, when coal and wood smoke combined with other particulates in the air that resulted in the death of over 4000 people! Since that time, wood and coal burning have been banned in London, and other larger cities in England.

*It is misguided to allow burning to the super high point where a burning ban has to be mandated to get dangerous particulates to go down. Why not ban burning so that the particle pollution doesn’t go so high in the first place?

In summary, the opacity standard just doesn’t cut it, because a visual inspection is a small part of the problem. Just as cigarettes have now been banned in bars and restaurants in many states, so wood smoke needs to be banned. We haven’t accomplished anything with indoor bans if you leave the bar and enter a different world of smoke—outdoor smoke that filters into the homes and lungs of others.

People may have a “right” to burn wood, but do they have a right to invade the airspace of others who have a right and a need to breathe clean air?

It is barbaric to burn wood in urban areas. Especially with asthma skyrocketing in children and in people of all ages, and other lung-related cancers and other serious environmentally-related diseases. The Air Board people find it easier to hang onto their ways, without opening up to a world that is now besieged with global warming and major illnesses like never before. We need new solutions—and new ways to address the problem. Ban wood smoke!

Julie Mellum
President, Take Back the Air
4316 Upton Ave S, Suite 204, Minneapolis, MN 55410
612-926-1093 Website:
*Fighting neighborhood air pollution from wood smoke, scented laundry products, and other cancer-causing pollutants*

Julie is serving as the Mid-West Director for CAR, Inc.

ED: The BAAQMD has used 'smoke signals' since the founding of Burning Issues/Clean Air Revival. It has not worked. See Dr. Wayne Ott's Christmas Comparison.

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