> One study found that nurses averaged 25 touches per shift to their face, eyes, or N95 respirator during extended use.
How problematic that touching is probably scales with how problematic your environment is. They're pretty sponge-like. Wearing a surgical mask over an N95 would help a lot.
In a controlled biosafety level 3 lab, "single use" things are definitely the most common, where everything exposed to the outside world is destroyed after you're done. What's worn underneath is washed and you're forced to take a shower. So that's what you do if you know you're in a contaminated environment – not sure what I'd do in a public place.
How effective is the virus after the mask has been unused for a while (so "cold", like a doorknob or a desk)? If it is not, the mask should be good to go then, doesn't it?
I use a reusable mask, and honestly, I don't wash it very often. It's there mostly so if I absentmindedly touch my nose I don't actually touch my nose, and so I never remove it until I've thoroughly washed my hands.
Source: https://www.journalofhospitalinfection.com/article/S0195-670...