I have moderate hearing loss and I used to shoot a lot. It was really scary to hang out at the shooting range and talk to the old timer highpower shooters. The most frequent thing they say is, What's that again?
I went to an audiogist and discussed my hearing loss w/ him. He told me that the plugs do great *if worn properly* to about 30dB reduction. He prefers them to muffs b/c you can insure a better seal. Adding muffs to plugs in theory will give you up to 55dB+ protection. However, according to my doc, once you get to about 35-40dB protection you have reached the limit. At that point, the sound waves are traveling through your boney head vs. the ear canal so you don't get any further attenuation. That said, I always wear plugs and muffs when shooting. Can't hurt, might help.
For REALLY LOUD situations, you can buy a helmet that encases your whole head and protects your hearing.
Finally, my doc sez if you have to talk loud to be heard, you should be wearing hearing protection. Problem is, you won't know it for 20 to 30 yrs.
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