Could someone please explain PM micrograms per cubic meter

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Could someone please explain PM micrograms per cubic meter

Postby turning_blue » Tue Oct 14, 2008 3:00 pm

http://apps.leg.wa.gov/documents/billdo ... A%2008.pdf

I would like to understand what this means. Thanks.
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proposed Wash. burn bans

Postby Ernest Grolimund » Tue Oct 14, 2008 4:25 pm

What does this proposed bill mean? I would like to know too. It is poorly written by a lawyer who seems to be having trouble trying to grapple with the wood burning problem. But they recognize there is a problem at least.

My state forecasts pm pollution from monitors and weather and mails warnings to asthmatics that problem days are coming so they can take more drugs and curtail activities outdoors. Washington seems to be trying to ban burning to some degree on days when they think pm pollution will be bad. If they see a prediction for 25 mcg/cubic meter, further banning or a complete ban may be ordered, because even EPA certified stoves cause about 5 mcg/cubic meter and two in series would cause 10 mcg. The total would then be 35 mcg which is illegal. They are trying to provide a safety factor by banning at 25 mcg which is a good idea. Washington gets a lot of rain and fog and the water adheres to pm causing it to sink more and causing more pollution. They are having a lot of problems so they have been a leader in the fight against woodburning pollution. They are studying the numbers like me apparently and DR. Brown and realize that ambient pm from oil burning in calm winds causes pm to go to 30 mcg/ cubic meter and this is very close to the legal limit. They recognize that the glass is full so to speak and the glass or atmosphere cannot handle any more pm from woodburning. They do not recognize that hospitals are saying asthma attacks start at 30 mcg/c.m. for a few hours but they are close to that limit. It is a start in the right direction but wicked complicated. They need to K.I.S.S. but everything is a fight down here on earth. Wish I was in heaven instead of this mild hell.
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pm/cubic meter meaning

Postby Ernest Grolimund » Tue Oct 14, 2008 5:16 pm

I keep forgetting I am an engineer by training at least and numbers and units come easy to me. Pm means particulate matter or soot. Mcg means micrograms and this is a measure of mass or weight. Cubic meter means a volume that is a cube with sides of 1 meter. Mcg/cubic meter is a metric system expression of mass/volume. In english measurements, the units might be lbs/cubic foot or psf. I get tired of writing mcg/cubic meter so I write mcg/c.m. but that isn't exactly standard. I just can't type m to the 3rd power. I can see that I should really keep it simple when writing for the public. You are pretty well informed and smart so if you are having trouble understanding me, then others will too. Non scientists rule, so I have to write to people like you. You are not dumb to ask this question and I have learned something from it.
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Postby turning_blue » Tue Oct 14, 2008 5:51 pm

Thanks Ernest, for trying to explain this. It's too complicated for me. I'll have to reread this. Maybe I need a mental picture. I have major math anxiety, so almost anything with numbers makes me panic. I do want to understand this though. I'll get it.....one day :oops: [/i]
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Postby Wilberforce » Tue Oct 14, 2008 6:33 pm

Ernest: Do you use windows? Look in programs>accessories>system tools>character map.
There you will find the Greek letters and superscripts. (mcg/c.m. becomes µg/m³)
Or you may copy/paste from this post. I use Tahoma font.

Blue: Help is on the way. I am writing an essay for all to understand PM. It might be in a
question-answer format, from which we can construct a FAQ page for the non-scientists.
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Postby turning_blue » Wed Oct 15, 2008 6:41 am

Thank you so much Woodnyet. Could you explain the ambient air part too? Also, could you explain how this air with the PM, gasses, toxins etc. travel from chimney to ground level and hovers around properties and enters homes so easily? Also, the nanoparticulates and "zero-visible smoke" and again what the problem is with the 20% opacity rule.

Important things here I think the public and "nonscientists" need to know. It's crucial for argument too. Pictures are what we need too. I wonder if we could get some good diagrams. I appreciate all your time that you put into this. We need you!

Neighbors/residents have to do more than "close windows." They have to buy expensive air purifiers and some move.
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Pm

Postby Ernest Grolimund » Wed Oct 15, 2008 10:01 am

Woody: I can't use windows. Too much smoke. Only kidding. I'll try to dig out the abbreviations. I'm not that great with computers.

Blue: 80% of the exhaust gases are nitrogen and carbon dioxide. They are equal in weight, or density, to existing air, so when hot they are less dense and rise or disperse. But the other 20% are toxic gases with heavier molecular weights so they sink. The particulate is in both so it drops with the toxic gases into a ground hugging plume that is largely invisible most of the time. When it hits a house, it gets caught in an eddy current or air pocket where wind is low. There is positive pressure which pushes it into houses by infiltration through cracks around windows and sills and doors. The toxic gases sink like a heavy liquid sinks in a lighter one. Think of mixing oil and water for a salad dressing. The lighter oil rises. A heavy rock sinks. It is a density phenomena. A hot air balloon rises because the hotter air is lighter.

I think of ambient pm as the pm in air that is everywhere around a city. When you go out in the country around Pittsburgh say near Murrysville and you look back to Pittsburgh you can see an evenly distributed haze that is brownish. That is the ambient particulate matter. Superimposed on that are the plumes from stoves that 10' - 20' wide and 10" high more or less that hug the ground but are invisible. They cause a streaked air pattern and are not dispersed so they are not part of the ambient air. However, if everyone burned wood, the woodsmoke would become part of the ambient air and in an inversion with no air movement all the smoke goes into a pool and the ambient air goes up. The woodsmoke is everywhere, then. That is how I imagine it anyhow.
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