But my initial thoughts for the mask is in the EDC in the event of a building collapse. If trapped, at least there's something that can reduce the stress or discomfort.
Before you buy too many N95 masks, you may want to try wearing one for a number of hours. If being trapped in a building collapse is the scenario you're mostly thinking about, then you will likely be stuck for hours, if not days. High filtration masks like an N95 take some effort to breathe through and could fatigue you eventually. Just the discomfort/effort could make you take it off in your sleep unintentionally.
The valve helps make things easier on the exhale, but does nothing for the inhale. If the mask doesn't fit that well, then maybe the respiratory effort won't be too bad. Or you might just consider getting more run-of-the-mill dust masks which should work fine, are cheap, and are easy to breathe through. I can't say for certain, but I doubt that rubble and splintered wood involves much sub-micron size particulates in the air anyway. Actually, dust may clog up an N95 mask pretty quickly compared to a dust mask, making it even harder to breathe than it already is. Anyway, just a thought.
Oh, but wildfires do generate extremely tiny soot particles, so you can still go ahead and buy them for that purpose. As RAS posted, it worked great in smoke for him. Any excuse to buy cool stuff to be prepared, right? <img src="/images/graemlins/wink.gif" alt="" />