Good points regarding filters and such. Probably good to break it down into three catagories, in increasing benefit:

1) filter only (hanky, dust mask).
2) something that handles carbon monoxide (EVACU8, EVAC+)
3) SCBA.

A SCBA would obviously be best, but AFAIK, these are all expensive and rather bulky. Certainly I'd be interested in knowing more about the SCBA options.

-john