On the Fact that Even the CDC as Recently as June of 2020 Has Concluded that Wearing an n95 Mask for More than an Hour Straight Can Induce Significant Health Problems - https://blogs.cdc.gov/niosh-science-blog/2020/06/10/ppe-burden/

And the manufacturers apparently know this as I recently saw a used one in a Dunkin Donuts bathroom with the words, "Misuse May Result In Sickness or Death", printed right on it. So, yeah, if you're forced to wear one of these suckers, take it off for a few minutes every hour and, you know, BREATHE!!