[Stoves] measuring soot particle load in kitchen

[Tami Bond]

Hi Andrew,
I think we should know more about the goal of the study.

Do they want to know amount emitted, or room concentration? Those are 
different. The sticky paper will get you only room concentration (if that).

Black particles will indeed change the reflectance of a light-colored 
collection film.

I haven't heard of this collection method before, but here are some 
concerns:

- Deposition will be by particle diffusion to the surface, OR 
gravitational deposition if the surface is horizontal. Particles of this 
size (~80-200 nm) don't diffuse very efficiently-- SMALL particles (<20 
nm) do. Nor are the particles very much subject to gravitational 
deposition-- LARGE particles (>2000 nm) deposit better. At very least 
there would have to be some calibration experiments. The users do not 
have to do them, but some literature should be found.

- Reflectance will change not just because of black particles, but 
because of dust. Since deposition is more efficient for large particles 
(like dust), these papers could get a lot of dust on them, and such 
measurements would not be good proxies for stove emissions.

- Reflectance will NOT change because of the white/yellowish particles 
that form a lot of stove emissions. So again, it's not a good proxy for 
stove emissions.

The likelihood of such a paper obtaining enough deposit to measure after 
one operation of the stove is extremely low. Even if it did work, you 
would want at least a week or a month collection.

The first question to ask is, What do they want to know? Second, why? 
Third, how well do they need to know it? Are they looking at 
interventions-- in which case you want to distinguish the *difference* 
between two stoves? Or are they just trying to determine whether the 
kitchens are polluted-- for which eyes and nose could do just as well? 
Certainly there are many other outcomes, but we need to start by knowing 
what they are.

Best,
Tami

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
Assistant Professor
Arthur & Virginia Naumann Endowed Faculty Scholar
Dept. of Civil & Environmental Engineering
University of Illinois, Urbana-Champaign
Newmark Civil Engineering Laboratory, MC-250   (01)217-244-5277
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