I was actually wondering about this recently and I started thinking about how loud of sounds people working on the deck of an aircraft carrier would be exposed to. I found this interesting article about improving the hearing protection for them, because it turns out even for people who actually use both forms like they are supposed to (most of the people in the jobs exposed to the loudest sounds do, it would likely still be at the pain level for them if they only wore one so they have good motivation) it still isn’t enough for a full workday of exposure.

Here’s the link: apps.dtic.mil/sti/pdfs/ADA455113.pdf. The exposure is something like 145-155 dB. They say a final checker will get to the safe limit in only a few takeoffs, and that assumes that they can recover in a below 84 dB environment when they aren’t working, which apparently also doesn’t happen. It seems like it isn’t really a solved problem of how to protect people being exposed to this kind of sound level.