As an audio engineer for 17 years and having traveled the world doing sound, I finally have a moment to address this matter of concern. Hearing damage is permanent; until someone invents nanobots to restore cilia function.

According to NIOSH standards, here are the decibel level exposure recommendations to avoid damage:

A-weighted, slow response
85 dB 8 hours
88 dB 4 hours
91 dB 2 hours
94 dB 1 hour
97 dB 30 minutes
100 dB 15 minutes
103 dB 7.5 minutes
etc

Over the years, I have consistently measured sound (live or DJ) at dance events between 95-100 dB. This means that permanent damage begins between 2-6 songs into a set. And that's if you start at a zero baseline for the day. What people don't realize is that damage doesn't just occur at loud levels, but is also due to time of exposure.

If you're in a loud bar (91 dB) for two hours straight, then you are beginning to permanently damage your hearing. Generally, it starts in the high frequencies so you don't really notice. If you walk away from a concert or live performance and you hear ringing or everything feels muffled, you have done some amount of damage. Very likely much of your hearing will come back, but you may be missing pockets of different frequency ranges and honestly, some of it just won't come back.

The upshot of this is that you will have trouble hearing your grandkids. Thinking about this now will prevent lots of frustration later in life, as being disconnected from one of our major senses greatly impacts quality of life as we age.

Prevention

The easiest symptom to address is fatigued hearing: use hearing protection. There are all sorts of ways to do this - and no - paper towels or cotton in the ears don't help at all.

From $2 foam ear plugs to $150 custom molded plugs, each serves a purpose. The cheaper earplugs offer the most protection, but come at the cost of sound quality. Foam plugs block high frequencies which makes it tough to hear articulation. There are musician ear plugs called etymotic ear plugs that offer a balance of protection while maintaining quality. These run from $15-$75 and are of varying quality. I believe this is the minimum investment necessary for enjoyment and protection, especially for dancers.

Beyond that, you can go to an audiologist and have a mold of your ear canals made. This costs about $50-60 and then you send that mold to a company that specializes in custom earplugs. These usually cost $100-150 and offer the best protection along with the most retention of the sound. They are called frequency flat because they suppress sound waves over all audible frequencies equally.

These also allow for different levels of decibel attenuation, which means making sound quieter. Remember, sound is simply air pressure that moves at a certain rate. The pair I use professionally have 9, 15, and 25 dB attenuators. If you reference the table above with time vs. damage, you can select which level of attenuation you want and still keep your hearing safe while the concert still feels 'loud'.

Remember, those exposure levels come from the idea of just waking up and having fresh ears. If you've been at work in a loud environment or in a loud restaurant, then your time of exposure before damage is decreased.

The first line of defense is hearing protection.

Causes

Speaking with the organizer to ask the sound engineers or DJs to bring the volume down to appropriate levels is the next line of defense. This can sometimes be tough due to political reasons, ego, or ignorance on the subject. It's not easy to tell anyone to "turn down" and have it not land harshly. DJs tend to want to "feel" the music and that's totally fair. What's not fair is that when you can feel it in the back of the room where the DJ or sound board is, it means that the sound pressure level on the dance floor is at unacceptable levels.

Sometimes, bands have their amplifiers far too loud and there is nothing that the sound engineer can do. In this case, many times, the band's instruments aren't even being sent through the PA. The issue is this: for vocals to be heard, they have to be LOUDER than the instruments on stage. When the issue lies with the band, egos can make negotiation difficult. There is definitely sound logic to things being loud.

We hear more evenly at higher levels and tube electronics sound best when they are being driven hard. What's difficult is if a band is unaware that they are permanently harming dancers and concert attendees in the name of 'tone'.

When I was an organizer for the Fusion Exchange, we built in safe decibel policies into our contracts. If any of our bands went above a specified stage volume, they would be asked to turn down. If they refused, they were in breach of contract, fired on the spot, and we were no longer legally obligated to pay them. That's how serious the FX crew and leadership were about preserving our attendees' hearing. We never had to act on that clause.

A simple chat with bands who respected their audience and considered their impact, went a long way to preventing putting anyone in that predicament.

I'm personally sick of bands hurting my friends and dance family and awareness is the best thing we can do to ensure everyone's sanity and safety.

It all starts with the stage and hiring conscientious bands who understand dynamic range and their audience's needs. We are not there to scream and yell. We are not there to have our hearing mutilated. We are not there to have our future enjoyment stripped from us. We are there to dance and feel the pulse and listen to words of many sinner sages. And that can be done at safe and enjoyable levels for everyone.

If you're an organizer, I'm more than happy to help you write contracts that protect you and your attendees and keep bands aware of what we're hiring them to do for us. And seriously, if a band doesn't respect your attendees, fire them. They are physically harming your scene. You wouldn't let someone slowly scar your eyeball over years and years until you couldn't see. Why do you let bands do that to your ears?

If you're a dancer and simply want more information about hearing and hearing protection, feel free to pm me and I will gladly point you in the direction of knowledge.

Most importantly, educate yourselves, your friends, your scene organizers, and the bands you hire that you want to be able to hear your grandkids or friends when you get old, whatever your preference may be.

Hearing loss has been linked to Alzheimer's and other degenerative diseases as the perception of language stimulates the brain in specific ways our whole lives. Losing that, we literally lose a part of our brain and a part of ourselves.

I plan on writing more on this subject and if there are any topics you'd like me to address or are scene specific, please let me know via the comments.