Originally Posted by
J. Barron DeJong
I puzzled out the pattern on this chart, and it looks like if two people wearing well fitted N95’s are good for 2500 hours, then a person wearing a well fitted N95 should be safe from an unmasked person for 25 hours.
So, if you’re shopping, at an airport, etc. you can be quite safe by wearing a good fitting N95, regardless of what others around you are doing.
If spending a significant amount of time with someone who is high risk, in a close space, then it may be a good idea for both to mask up.
IANAD