Naked Science Forum

General Science => General Science => Topic started by: chris on 09/09/2018 11:33:11

Title: How small is a smoke particle?
Post by: chris on 09/09/2018 11:33:11
I'm putting together a piece to make viruses and the spread of infection more comprehensible for non-specialists. In explaining why the particles spread through the air and remain airborne for so long I would like to use an analogy like "these viruses are smaller than some of the particles of smoke that come off the end of a cigarette / exhaust pipe".

I thought I'd better fact check this first!

A flu virus is about 100nm (1/10,000th mm); but how big is an average smoke particle?
Title: Re: How small is a smoke particle?
Post by: chris on 23/11/2018 16:42:53
No one helped me with this :(
Title: Re: How small is a smoke particle?
Post by: chiralSPO on 23/11/2018 19:35:27
Smoke particles range from molecule size (polycyclic aromatic hydrocarbons, which can be as small as about 1 nm across; https://en.wikipedia.org/wiki/Pyrene) up to very large particles. Often people care about how much particulate mater below 2.5 Ám across (PM2.5) is in the air: https://airnow.gov/index.cfm?action=aqibasics.particle

This 2.5 Ám limit puts them much larger than viruses (more like bacteria), but I don't know what the distribution of smoke particle sizes is.
Title: Re: How small is a smoke particle?
Post by: Colin2B on 25/11/2018 07:29:30
Wood smoke 0.4 - 0.7 mm
Cigarette smoke, varies quite a bit but generally 0.2 - 0.8 m

Must have missed this one when it came up
Title: Re: How small is a smoke particle?
Post by: chiralSPO on 25/11/2018 22:02:11
Wood smoke 0.4 - 0.7 mm
Cigarette smoke, varies quite a bit but generally 0.2 - 0.8 m
Those both sound big...   I've never heard of 0.2 m smoke particles before! Perhaps some typos involved?? ;)
Title: Re: How small is a smoke particle?
Post by: Colin2B on 25/11/2018 22:21:05
Wood smoke 0.4 - 0.7 mm
Cigarette smoke, varies quite a bit but generally 0.2 - 0.8 m
Those both sound big...   I've never heard of 0.2 m smoke particles before! Perhaps some typos involved?? ;)
Whoops, forgot to edit in the μ when posting :-[