I found most people dont know about this or think about this until there is a home purchase and home inspection -- that is when it is revealed, and typically when it is remediated as part of the purchase contingencies. If youre living in the same home for a while, you wouldnt typically know. Also, if you are a renter, you probably wont know and the landlord will probably purposefully not want to test.

In my state, the state forces some of these tests (e.g., smoke detector) as part of the sales process so at least there is some hook for testing.