Funny, I was just using a N95 mask, cleaning out some rodent infestation. They are much better than a bandanna, even a red one, and they are cheap and easy to use. When necessary, I would pair a mask with safety goggles - not as good as SCBA breathing apparatus, but a lot more available.

You can purchase a n95 mask packaged with goggles and ear protection. I have some of these stashed around the premises so that I can get my hands on them when the old castle becomes dust and splinters in the next big earthquake.