[jyl]

So, I've been reading argument that the so-called N95 mask is not effective at stopping the flu because viruses are smaller than the mask's filter size. But perhaps the things that viruses travel on - dust particles, etc - are large enough to be blocked, thus making the masks at least helpful?

Dunno, but if there is a swine flu pandemic I wouldn't rule out wearing a mask.

Edit: ok, did some reading. Hospital masks are those cloth masks with tie straps that are worn in, well, hospitals. NIOSH certified N95 respirators are those molded masks, usually with elastic straps and metal tabs to fit the nose. The N95 respirators are supposed to filter 95 pct of particles. Airborne flu viruses are transmitted on droplets that are large enough for the N95 mask to be effective. Two clinical studies have suggested these masks do reduce the chance of contracting flu, though they don't eliminate it. I havent found any study on how effective they are when worn by someone who has the flu. N95 masks are sold at Home Depot in contractor packs of 20 for $20, usually in painting section. But check the label, there are non N95 masks too. Some N95 masks have an exhalation valve which would obviously make them less useful if the wearer already has flu.


Well, I have two packs of them in the garage, just in case.