# Who is up for some math? (pollution question) **URL:** \ **Category:** Factual Questions\ **Created:** [August 18, 2000, 11:15pm UTC](https://boards.straightdope.com/t/who-is-up-for-some-math-pollution-question/29919 "2000-08-18T23:15:08Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![Zebra](https://avatars.discourse-cdn.com/v4/letter/z/c0e974/32.png) [@Zebra](https://boards.straightdope.com/u/Zebra)\ **Post date:** [August 18, 2000, 11:15pm UTC](https://boards.straightdope.com/t/who-is-up-for-some-math-pollution-question/29919/1 "2000-08-18T23:15:08Z")
This is my first post so please be gentle… I was reading the other day about some sort of air pollution and the fact that it was growing. I think it was monopolyfred-n-etheldiclortrimine or something like that. But then they go and say that it is up to ten parts per million in the atmosphere whereas only a few years ago it was only 1 part per million. Then I thought ‘Hey! This means absoultly nothing to me because I have no idea how big a “part” of atmosphere would be.’ So… How many parts are there in the atmosphere? How many parts of atmosphere are there in a ten by ten by ten foot room. If I was standing in that room and took a deep breath (avarage adult male non-smoker) and the pollution was 10 parts per million how much pollution did I suck down. Thanks ---
**Author:** ![The\_Ryan](https://avatars.discourse-cdn.com/v4/letter/t/7feea3/32.png) [@The\_Ryan](https://boards.straightdope.com/u/The_Ryan)\ **Post date:** [August 18, 2000, 11:27pm UTC](https://boards.straightdope.com/t/who-is-up-for-some-math-pollution-question/29919/2 "2000-08-18T23:27:10Z")
> [@](#): > > \*Originally posted by Zebra \* > So… > How many parts are there in the atmosphere? I don’t think you understand. “part” is a unitless measure. If some food is 10 per cent fat, how much is a cent? It’s one hundred times whatever the original amount is. How many parts of atmosphere are there in a ten by ten by ten foot room. [/quote] Ummmm… 1,000 cubic feet? > [@](#): > > If I was standing in that room and took a deep breath (avarage adult male non-smoker) and the pollution was 10 parts per million how much pollution did I suck down. > \*\* Somewhere around ten cubic millimeters. ---
**Author:** ![Smeghead](https://avatars.discourse-cdn.com/v4/letter/s/f1d935/32.png) [@Smeghead](https://boards.straightdope.com/u/Smeghead)\ **Post date:** [August 18, 2000, 11:38pm UTC](https://boards.straightdope.com/t/who-is-up-for-some-math-pollution-question/29919/3 "2000-08-18T23:38:10Z")
> [@](#): > > \*Originally posted by Zebra \* > \*\*If I was standing in that room and took a deep breath (avarage adult male non-smoker) and the pollution was 10 parts per million how much pollution did I suck down. > > Thanks \*\* Take all the air in your lungs. Divide it into one million equal parts (by volume, presumably, though this will no doubt spark off yet another lively debate). 10 of those one million parts are pure pollution. The rest are pure air. “Part” can refer to anything or nothing. If you have a million gallons, one part per million is one gallon. That’s where that handy “per” comes in. ---
**Author:** ![JonF](https://avatars.discourse-cdn.com/v4/letter/j/cab0a1/32.png) [@JonF](https://boards.straightdope.com/u/JonF)\ **Post date:** [August 18, 2000, 11:46pm UTC](https://boards.straightdope.com/t/who-is-up-for-some-math-pollution-question/29919/4 "2000-08-18T23:46:38Z")
> [@](#): > > f I was standing in that room and took a deep breath (avarage adult male non-smoker) and the pollution was 10 parts per million how much pollution did I suck down. The average adult breath is around 0.5 liters (it varies a lot around that). 10 parts per million (parts) is 10/1,000,000 or 0.00001. 0.00001_0.5 liters = 0.000005 liters or 5 milliliters or 0.3 cubic inches. Or 4_10[sup]-9[/sup] acre-feet (courtesy of [Unit Conversions](http://webphysics.ph.msstate.edu/units/)). ---
**Author:** ![Steve-o](https://avatars.discourse-cdn.com/v4/letter/s/ecc23a/32.png) [@Steve-o](https://boards.straightdope.com/u/Steve-o)\ **Post date:** [August 19, 2000, 3:19am UTC](https://boards.straightdope.com/t/who-is-up-for-some-math-pollution-question/29919/5 "2000-08-19T03:19:28Z")
0.000005 liters = 5 microliters ---
**Author:** ![Zebra](https://avatars.discourse-cdn.com/v4/letter/z/c0e974/32.png) [@Zebra](https://boards.straightdope.com/u/Zebra)\ **Post date:** [August 19, 2000, 5:05am UTC](https://boards.straightdope.com/t/who-is-up-for-some-math-pollution-question/29919/6 "2000-08-19T05:05:08Z")
How very silly of me. I don’t know why I didn’t realize it right off but sometimes… Anyway thanks for the answeres. ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [August 19, 2000, 5:15am UTC](https://boards.straightdope.com/t/who-is-up-for-some-math-pollution-question/29919/7 "2000-08-19T05:15:06Z")
Or put it another way, “ppm” (“parts per million”) is analogous to “percent” (“parts per hundred”). One ppm is equal to 0.0001%.