FDA guidelines dictate that a single use mask should, as the name suggests, be tossed after “single use.” However, the FDA doesn't completely define just what “single use” means.
A better way of approaching the question is “How long should I use my single use mask for?” The answer is about 24 hours, though, personally, I wouldn’t use one for more than eight hours straight.
Because masks are so widely available, we should err on the side of caution instead of conservation. “It’s your health, why risk it.”
