certain guns if fired right next to the ear can cause sudden loss in that frequency range. Unless of course it blows your drum from over pressure.
Here i found this helpful http://www.gcaudio.com/resources/howtos/loudness.html
125db is where the pain begins definitely want to get away fast as possible at this level.
180db is the instant threshold where the tissue dies…
194db is loudest sound possible. I am not sure if this is accurate the military may have access to something louder.
I believe the IPOD is 105 db. max for severe hard of hearing that might be fine, definitely not for those with normal hearing.
Now I think I have to go look and see if someone answered my question about whether 90db would have the same damaging effect on someone with moderate to severe loss as it would have on someone with normal hearing.
I have not meet an audiologist or doctor that has actually told me the answer to that question.