I have been looking at getting some face masks for both my EDC and home kits mainly as a protection against smoke and dust, and was going to get some N95 face masks. Having just got back from seeing the movie Contagion (it was excellent!) I am now thinking I might want to upgrade the masks.

For those that don't know this movie, there is a rather nasty virus being spread around the world that has flu like symptoms but kills. The virus is spread by directly touching a carrier, and also touching a surface a carrier has previously touched (a mobile phone, an ATM, a pole on a bus etc). The virus was also airborne.

It made me wonder what sort of masks would provide protection from such a virus (obviously gloves would also be needed) but be suitable for EDC, and suitable for a home kit? If you are getting a mask with separate filters, how many filters would you need? Without getting a full on biological safe suit, what could you get to help in this kind of situation?