gogi and christian:

Thank you both for sharing your technical expertise on the subject.

Personally, from everything that I've experienced and learned along the way, wearing the N95 face mask in adverse and/or threatening environments pays dividends. As mentioned before, I plan to continue wearing this mask well after this pandemic is over when I feel it's necessary.

If you guys don't agree with the test results regarding the N95's ability to lower CO levels, than that's your prerogative. Maybe you guys are right and the test results are wrong...what the hell do I know.

Seeing as you both appear to be in question about what "Expired CO" is, I have to assume that the experts who use this term frequently in their technical journals and published test results are using this term incorrectly.

In any event, none of this matters to me either. The only thing that concerns me is the masks ability to block at least some of the contaminants in the air to help protect my lungs and prevent the spread of this virus.

In your expert opinions: Does the N95 mask help, or not?