Roger on that - the PAPR hoods are pretty spendy, outside my reach. I've spent some drill time during S&R, moving heavy stuff to simulate digging in rubble, the N95 mask with an exhalation valve helps alot over an N95 without one, but it really does wear you down to breath exclusively through them. And I found that eventually the N95 tends to collapse on the sides, allowing air to infiltrate (this was when I tested masks while chainsawing, after 2 hours the N95 was pretty collapsed, and so was I). I also have a half-face mask and combine that with closed goggles when I paint or sand, my glasses steam so bad though its not very conducive to working very much, only the cheaper type of goggles that look like glasses themselves and fit over the top of my glasses really work. I'll take my chances with the full face mask, and try to keep my exertions down, and stay within my limitations.