Military hearing tests are not much different than civilian ones… except…
Time moves slower when you’re locked inside a dark metal box. In my estimation I was in that hearing booth for at least 30 minutes before ripping off my headphones and busting out. It actually wasn’t completely dark, but I take hearing tests with my eyes closed and try not to move. I’ve had mild hearing loss since experiencing a rash of ear infections as a kid. They culminated in three surgeries and, as one of my doctors put it, scar tissue that “looks like Freddy Kruger’s face.” The test is always stressful for me. This one would not end.
I looked around the room as my eyes adjusted and spotted the technician running my test. She looked startled, but appeared to know why I was out. During the test I kept hearing a strange, staticy “click click” sound followed by tones I had already heard and mashed my little red button to acknowledge.
“What are you doing?” I asked.
“You’re failing sir,” She replied.
“Ok, and?” I waited for a moment but she stayed silent. “Why isn’t it ending then?” She looked at me and blushed a little then cleared her throat.
“I’ve been restarting it. I need you to pass or you’ll have to see the doctor.”
“So, write that down that I failed and let me go see the doctor.” I said. Terror entered her eyes. She was about to object when I stopped her. “I’ll tell him I i insisted.”
She reluctantly complied, printed out my failed test, and told me to wait in the corner for the doctor.
Turns out my brain looks like everyone else’s… mostly
The “doctor” met me in a small, windowless room full of filing cabinets. He was a US Air Force officer, but he was clearly from somewhere else. I didn’t notice as he looked over my paperwork but then he spoke to me in a thick accent. I couldn’t place it, mainly because I was distracted by the fact that he only had three front teeth.
“Basically I do not want to do the paper works. They are a pain in my ass.” No exaggeration, that’s what he told me. “You come back tomorrow. You’ll pass.”
I most certainly did not pass. In fact, I rode my motorcycle to work just to make sure nothing was too quiet before the redo. My second test was identical, though: a 30 dB shift in my left ear only. That was alarming to every other doctor except Major Care-Less. I didn’t know it at the time but unilateral shifts that severe are really uncommon unless you have some known trauma… or a brain tumor. Hence the brain scan.
That showed nothing except a mild Chiari Malformation (my brain tissue extends into my spinal canal) . It doesn’t actually affect me any way, but I choose to believe it’s there because my brain was just too big to fit into a normal skull. In any case, no one could figure out what had caused my sudden hearing loss.
Then the light-bulb moment struck
Shortly after all of the tests and evaluations came up empty, I was reassigned from missile maintenance to the munitions safety and training office. As I was finishing packing up one day, I heard an all-too-familiar pop from behind the shop. Someone had just released the pressure on the storage tank of our mobile high-pressure compressor. It was something I’d done hundreds of times myself. The closest thing I can compare it to is a shotgun blast, followed by the high pitched hiss of compressed air.
The sound echoed through my skull and made my left ear throb despite the fact that I was inside. Then it hit me. I knew exactly what had caused my hearing loss. The compressor.
I replayed all of the times I had gone out to release the pressure on that unit in slow-motion. When all the tool kits were open and people were working in the shop it was easy to grab some ear plugs and a pair of ear muffs (both were required for that operation) and run to the back pad to release the air. But that’s not what typically happened.
Typically we would only run it for half a day and then turn off the engine. Inevitably we would forget the tank was still pressurized until all of the tools and supplies were inventoried and locked up for the day. No one wanted to sign anything back out at that point, so we (or at least I) had a habit of running to the pad and plugging our ears with our fingers. That meant one hand had to dislodge to pull the pin. I always used my left.
Protect yo selfs
I don’t usually get too technical in these posts, but you can’t grow your hearing back. Here are a few things to consider about hearing protection:
- The goal for using hearing protection is to attenuate noise levels to a safe level. For example, if a worker is exposed to 95 dB, their hearing protector needs to provide either 5 dB (to meet the OSHA PEL) or 10 dB (to meet the NIOSH PEL) of protection.
- The “best” hearing protection is the model you wear correctly and consistently.
- Individual fit testing can aid in determining this for users.
- An easy test for ear canal inserts is to cup your hand over your ear. If there is no change in sound when doing so, the protector is most likely inserted properly.
- Noise Reduction Ratings (NRR) found on hearing protectors are determined in a laboratory setting. Actual noise reduction depends on how it is used (see first bullet).
- “Double” hearing protection through the use of ear canal inserts and the addition of ear muffs does not provide “double” the attenuation.
- When both types are worn properly, the addition of muffs only adds about 5 dB of protection (for more information see http://www.caohc.org/)
Here’s the other thing
I have no excuse for plugging my ears with my fingers. I knew it was wrong. Procedures aren’t exactly negotiable in the military (as long as you didn’t get caught). I even knew that it hurt. But understanding risk isn’t always intuitive. I had no idea that a few seconds every day could cause permanent damage. Now that I know, it’s easy to say my actions were dumb. That goes for any stupid action by anyone, really.
But next time you start down that path just take a moment and consider how many times you’ve knowingly taken a risk, lost on that bet, and then thought “well that was dumb.” Sometimes we don’t know what we don’t know.