: Hi Bob,
: Check out Lab Safety, http://www.labsafety.com They have a very large
: selection of respirators and filters. Don't bother with the paper dust
: mask Ian suggested. They don't seal around your face and They DON"T
: WORK. Almost all filters used for fumes will filter out dust just as well.
: Dust particles are a larger particulate then that of fumes from chemicals.
: The only thing is they will clog sooner from dust. Lab Safety specializes
: in protective equipment and they should be able to point you in the right
: direction for the proper filter.

Kent is right,

My brother, an indoor air quality scientist, once told me that paper dust masks are just "feel good" tools. They only stop the microscopic "boulders" and "limbs" that would have been trapped by the body's own filter mechanisms (snot and hair) while the smaller, more dangerous particulates would easily migrate to the vulnerable areas of our bodies. Definately use a respirator, the replacement cartridges are cheap and most have a snap apart lid with a pre-filter that can be washed(looks like a piece of scotch-brite pad). Cedar can be an especially nasty irritant. Good luck, work safe.