i did some research, not much, before buying a noise generator for my kid. Basically long term exposure to any level of "noise" may be "harmful". I don't recall the mechanics of how, though. I think something like <4 hours per day was considered "acceptable". So if you're already near a laptop fan all day and then you run noise machine at night to sleep...
Believe me, sometimes tinnitus means i don't care if i damage it more, i just need outside to be slightly louder than inside my head.
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.
Believe me, sometimes tinnitus means i don't care if i damage it more, i just need outside to be slightly louder than inside my head.