Surely there is some level of noise for children (and adults) that is both safe and helpful. You're never going to have complete silence in the real world.
I use the Snooz white noise machine and their companion bluetooth app actually comes with a sound level display in dB that helps you make sure you're not setting it too loud in settings like a baby's nursery.
my master bathroom is somewhere ~7dB according to my cellphones, one of which i think i calibrated correctly. The second hand of the clock sounds like a movie revolver hammer cock.
There is a difference between like HVAC and the "noise floor" of a house, and pumping additional noise in. I'm just saying that a "noise machine" may not be a silver bullet. And i even said that me and the wife use it because tinnitus already sucks.
I use the Snooz white noise machine and their companion bluetooth app actually comes with a sound level display in dB that helps you make sure you're not setting it too loud in settings like a baby's nursery.