you do not listen in dBfs. dBfs is a scale for a numeric signal. for x dBfs you can have several values of dBspl.is this a reply to me?
I was not fully precise.
What I mean is that with reasonable volume you hardly (if even) can hear isolated -60dBfs sounds (let alone masked).
test with your listening volume for example here: https://www.audiocheck.net/audiotests_dynamiccheck.php