Cloth Masks Don’t Protect Against Wildfire Smoke

Photo: Joachim Zens, Shutterstock
Photo: Joachim Zens, Shutterstock

If you are living in a literal hellscape (as much of the western United States is at this point), you know that you can wear masks to protect yourself from coronavirus, and masks to protect yourself from the particulates in wildfire smoke. However: these are not necessarily the same masks.

Cloth masks block droplets, but not the fine particles in smoke. That’s because the holes in the weave are relatively large. (The virus is small, but microscopic droplets of spit and snot are big enough to be caught.) Just as you can smell a fart through a mask, you can also breathe in smoke. A cloth mask may block large pieces of ash floating through the air, so it’s better than nothing, but it’s not ideal. If you can possibly snag a better mask, you should.

For wildfires, you want something that seals tightly around your face and has a filter with teeny tiny holes. N95, P95 and R95 masks are recommended, as well as anything with numbers over 95 (like N99). These may be hard to find — N95s especially — but they really are better if you can get one.

If your wildfire mask has a valve, it’s ok to use it against smoke — in fact, that’s exactly the purpose these masks are made for. They will filter particles as you’re breathing in, but then allow you to breathe out without filtering anything. This is bad for coronavirus protection, but fine in situations where you are not around other people.

What if you live in a smoky area and need to be around other people? You can tape over the valve in your wildfire mask, or you can wear a cloth mask over your valved mask. You can also wear an N95 or similar mask that does not have a valve. Or, if circumstances allow, you can switch back and forth between a wildfire mask (like a valved N95) and a COVID mask (cloth or surgical style).

Log in to comment on this story!