AFAIK wrote:The N95 masks restrict oxygen flows so can not be worn for prolonged periods.
Partially true. Oxygen molecules pass easily thru the mask, but you shouldn't wear them for more than a few hours at a time without a break.
I wore them(N95 masks) for years at a plastic manufacturing plant, where we used them exclusively. 6 hours a day for years. Naturally, on breaks we removed them.
Fit is important, but where I worked, we weren't concerned with a virus, and so didn't worry too much about that. Of course, not having facial hair is key to a tight seal.
Here is some information on that(a study) if you care to look.
Effects of long-duration wearing of N95 respirator
and surgical facemask: a pilot studyhttp://medcraveonline.com/JLPRR/JLPRR-01-00021.pdf
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