Off-topic: Smoggy Days--why stay inside?

[samclem]

I've lived in some towns with poor air quality. Whenever especially bad air quality is forecast, the authorities advise susceptible people to remain indoors. Does anyone know why? Most homes exchange air with the outside in copious quantities (all the air volume in the home exchanged several times per hour). Few homes have filtration systems capable of getting rid of particulates that are really dangerous, and none can filter out noxious gasses. I've got to think composition of the air inside is virtually identical to the air outside. Plus, most homes have internal sources of air pollutants that significantly degrade air quality.

Still, the advice seems to be universal, so I must be missing something. Any ideas or guesses?

 

[AltaRed]

Never understood that either. I am guessing that some pollutants get dissolved out of the air in the evaporator of the A/C system.. and good quality air filters with a MEPA (?) rating of 11 or so can take allergens out of the air too.

 

[sgeeeee]

Indoor air quality can be worse than outdoor air according to the epa:

http://www.epa.gov/iaq/homes/index.html

 

[REWahoo]

Any ideas or guesses?

Less likely to hurt someone else than if you are driving a car when you croak?
More comfortable environment for EMS when they respond?

 

[yakers]

As a resident of southern California with air you can see, I would say the issue is exercise/ exertion which is more likely outside then inside. There is some mitigation through filters and the like but mostly its how active you are and how deep you breathe.
The point about indoor pollution is well taken. A lot of offices & bigger businesses have filters & monitoring but most homes don't. Another reason to keep working?

 

[TromboneAl]

I've wondered about this also. My uneducated guess is that indoors, the particulate pollution is going to settle out onto your floor and furniture instead of being breathed into your lungs. Outdoors the stuff is just blown around and new particles are produced.