Cloth Masks Do Not Protect Against Forest Fire Smoke
If you live in a literal hellish landscape (like much of the western United States at the moment), you know you can wear masks to protect yourself from the coronavirus, and masks to protect yourself from particulate matter in the smoke of wildfires. However: these are not necessarily the same masks.
Cloth masks block the entry of droplets, but not small smoke particles. This is because the holes in the braid are relatively large. (The virus is small, but the microscopic droplets of saliva and snot are large enough to be caught.) You can breathe in smoke just like you can smell fart through a mask . The sheet mask can block large chunks of ash floating in the air, so it’s better than nothing, but it’s not ideal. If you can find a better mask, you should.
In case of forest fires, you need something that covers your face tightly and has a filter with tiny holes. N95, P95 and R95 masks are recommended , as well as any masks with numbers greater than 95 (eg N99). They can be hard to find – especially the N95 – but they are really better if you can get them.
If your bushfire mask has a valve, you can use it against smoke – in fact, that’s what these masks are made for. They will filter particles as you breathe in, but then allow you to breathe out without filtering anything. This is bad for protection against coronavirus , but ok 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 cover the valve with a wildfire mask or wear a cloth mask over the valve mask. You can also wear an N95 mask or similar mask without a valve. Or, if circumstances permit, you can switch between a wildfire mask (such as an N95 with valve) and a COVID mask (cloth or surgical).