.Take this test to see how well you can hear high frequencies. Your ability to hear these tones may be somewhat dependent on your computer speakers, so turn it up fairly loud.
I can hear the 17kHz tone, barely. The 16kHz tone is loud and obnoxious to me. Since I am in my 50's, I figure that this is pretty good hearing for my age.
I have been very careful with my hearing. I only recall a few times in my life when I was exposed to very loud sounds. Once was at a concert that was so painfully loud that I was gritting my teeth. Several times, I have gone shooting without ear protection, but only with small .22 caliber. Once I shot a 9mm without plugs just to see what it sounded like. My ears rang for an hour. Finally, my oldest kid, when he was a baby, would cry so loud that it made a tearing noise in my ears. Ear plugs can definitely prevent shaken baby syndrome...
Interestingly, after I took this test, my ears felt stuffy for a while.
Hearos NRR 33dB -- The best ear plug in the world
If you use soft foam earplugs, be sure to roll them into a tiny cylinder with your fingers, then put them into your ear canal as far as you can. It is easier if the plugs are cold. Most people require some practice to do this properly.