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Q. How do I measure wood smoke from firewood? We want to do a comparison of different firewoods and find the one that has the least smoke emissions, provides the most heat, and burns the longest. We would like to really measure the smoke. Any ideas?
Scotts Valley, Calif.
A. Dearest Patricia,
If you listen carefully this time of year, you can almost hear it: the crackling of thousands of wood stoves firing up for a season of home heating. Unfortunately, the cozy glowing of all those stoves has a serious downside: a smoky, sooty smudge on local air quality.
Wood smoke emits all kinds of nasties [PDF], including benzene and formaldehyde, but the primary culprit is particulate matter (PM2.5), a mix of tiny particles that can penetrate deep into the lungs when inhaled and wreak all kinds of havoc. The stuff is linked to respiratory illness, chronic lung problems, cancer, and premature death -- so your desire to find the cleanest-burning logs possible is a vote for both air quality and personal health for you and your neighbors.
I admire the citizen-scientist pluck behind your wish to analyze and compare different types of wood smoke yourself, Patricia. Unfortunately, this is currently pretty tough to do unless you A) are an atmospheric scientist with access to sophisticated sampling tools, or B) have an extra $10,000 to $50,000 lying around to spend on said tools. I checked with Matthew Harper, air monitoring lead for the Puget Sound Clean Air Agency. He said you could use a handheld particle counter, the cheapest of which will run you a mere $300 to $500, but these devices probably aren’t accurate enough to distinguish the nuances between, say, hickory versus oak smoke.
But don’t hang up your lab coat just yet: There are still a few worthwhile experiments to be done.