Asbestos Exposure, need help!
TL;DR Don't worry, be happy.
In my non-professional, non-government opinion, you are overreacting. The risk with asbestos (as with smoking, radon and many similar things) is repeated exposure. That doesn't mean a single exposure has no effect, but the big problem is with repeated exposure. Something like, tearing up a floor each day, 200 x a year for 20 years. Not &quot;once&quot;. Plus, even though a KN95 mask may not be certified for asbestos, it will certainly help block the fibers. Certification is a tricky, and expensive, business. Especially in the past year, there are a lot of masks out there, of varying quality, that are not being certified for medical use or for asbestos or other specific things simply because any manufacturer right now, worldwide, can sell all the masks they can make as long as they meet some extremely basic design standards.
In general with asbestos, if you can cover it up, there is no danger. If there are other areas of the house (e.g., flooring in other rooms) that may have asbestos, you should probably get it tested first before working on it, or just cover it all up instead of rip &amp; replace.