Any of you guys read this study on the N95s?
These were just the ordinary ones from the National Strategic Stockpile.
Wow!...breathing 3% or 30,000 ppm CO2 does not sound like a recipe for health to me. Let alone restricting oxygen well below the below OSHA safety limits on O2, at under 17%
Certainly wouldn't want to wear one for any extended length of time...and imagine the extra stress on folks who are already not healthy if they wear these for hours on end.
We assessed the physiological impact upon healthcare workers of an N95 FFR with and without an exhalation valve, and measured the oxygen and carbon dioxide levels in the FFR’s dead space (FFR VD)
The timed mean mixed inhalation/exhalation FFR (mask) VD CO2 and O2 values, respectively, over 1 hour, for the FFR (2.9%, 16.6%) and the FFR-with-valve (2.9%, 16.7%) did not differ significantly by work rate or FFR model, and are comparable to other studies.
Although the FFR VD O2 level was lower than the Occupational Safety and Health Administration’s workplace standard (<19.5% O2 is considered deficient) and the FFR VD CO2 level was higher (0.5% CO2 as an 8-h time-weighted average, is normal), these standards apply to the ambient workplace atmosphere, not to the FFR VD.
Nonetheless, breathing-environment CO2 >3% has been associated with detrimental physiological effects, and prolonged breathing of CO2 at greater than the atmospheric level can cause symptoms (eg, headache, anxiety, and confusion) and the additional physiological stress of compensatory mechanisms.