Save Your Ears!
In 2010, I entered a film festival with 3 categories: diversity, character, and healthy choices. My co-producer and I chose the healthy choices category because I placed first in that category the year before. Out of all the 3 categories, this one was by far the easiest to brainstorm for because there are so many obvious ways to stay healthy. To remain competitive, we knew that we couldn't make an entry that said "eat healthy" or "go exercise," we needed something equally as relevant without being mainstream.
We eventually settled on the topic of "hearing health" and a statistic we used was "Excessive noise exposure is the most common cause of hearing loss." This lead me to a question though. How much noise is too much? And, can your ears repair themselves? Eventually, I did further research!
As it turns out, there's temporary and permanent hearing loss. When you go to a rock show and sit right in front of the speakers, you're hearing will be worse after the show but will, eventually, return to normal. The real problem occurs when you do this repeatedly. Every time you experience temporary hearing impairment, your hearing slowly and permanently degrades. So, the answer to my second question is yes and no. The ear can repair itself to an extent but can't hold up to extended abuse.
If you stand in front of the speakers at a show, you could experience 120 db of sound. After only 7 1/2 minutes, your hearing will start to degrade. I guess it's a common sense thing; don't stand by a jet taking off or in front of a back to the future-esque speaker, and you can keep your hearing forever!