Hearing loss is one of the most common military service-related injuries.
Consider what a Soldier in the line of duty can be exposed to from a noise and hearing loss perspective.
An AT4 anti-tank weapon may only last a second but the 187 decibel (dB) boom on noise is enough to cause immediate and irreparable damage. At 140 dB or higher immediate nerve damage can occur. A Bradley fighting Vehicle driving over asphalt can produce 130 decibels (dB) (damage within a few seconds) or a Black Hawk helicopter pulsating thrum at 106 dB damage within 15 – 30 minutes.
Will a piece of foam earplug protect an ear from this damaging noise? What compromises will occur when a soldier is in active combat with hearing loss? Will they hear critical information? Is combat duty induced hearing loss undermining the Soldiers ability to do their job?
Hearing Loss is a Soldier’s Dire Enemy
Mary Roach hits the firing range to discover what nearly every soldier knows: even mild hearing loss is devastating in battlefield situations, and earplugs, the common solution, may make things worse.
The United States Marine Corps buys a lot of earplugs.
You find them all around Camp Pendleton: under the bleachers at the firing range, in the bottoms of washing machines. They are effective, and cheap as bullets,which also turn up in the washing machines. (And, though you didn’t ask for it, here’s one more similarity between bullets and earplugs: Both have been used by physicians to protect their ears from screams. The Army Medical Department Journal states that the real reason soldiers in the pre-anesthesia era were given a bullet to bite was not to help them endure the pain but to quiet their screams.
For decades, earplugs and other passive hearing protection have been the main ammunition of military hearing conservation programs. There are those who would like this to change, who believe that the cost can be a great deal higher. That an earplug can be as lethal as a bullet.
Most earplugs reduce noise by 30-some decibels. This is helpful with a steady, grinding background din—a Bradley Fighting Vehicle clattering over asphalt (130 decibels), or the thrum of a Black Hawk helicopter (106 decibels). Thirty decibels is more significant than it sounds. Every 3-decibel increase in a loud noise cuts in half the amount of time one can be exposed without risking hearing damage. An unprotected human ear can spend eight hours a day exposed to 85 decibels (freeway noise, crowded restaurant) without incurring a hearing loss. At 115 decibels (chainsaw, mosh pit), safe exposure time falls to half a minute. The 187-decibel boom of an AT4 anti-tank weapon lasts a second, but even that ultrabrief exposure would, to an unprotected ear, mean a permanent downtick in hearing.
Earplugs are less helpful when the sounds they’re dampening include a human voice yelling to get down, say, or the charging handle of an opponent’s rifle. A soldier with an average hearing loss of 30 decibels may need a waiver to go back out and do his job; depending on what that job is, he may be a danger to himself and his unit. “What are we doing when we give them a pair of foam earplugs?” says Eric Fallon, who runs a training simulation for military audiologists a few times a year at Camp Pendleton. “We’re degrading their hearing to the point where, if this were a natural hearing loss, we’d be questioning whether they’re still deployable. If that’s not insanity, I don’t know what is.”
Excerpt from Article Hearing Loss Is a Soldier’s Dire Enemy