Grunt by Mary Roach Read Free Book Online

steering wheel appears to have been salvaged from a 1990s budget rental car. (And possibly was: General Dynamics, manufacturer of the Stryker, owns Chevrolet.)
    Mark ousts me from the driver’s seat so he can repark the vehicle. Brockhoff, pacing at the edge of the parking lot, has found some sort of plastic packing material. She darts over to the Stryker and stuffs it in behind the backmost tire. What follows is a noise you will find nowhere in the publications of military hearing professionals: a 40,000-pound Stryker backing up over an armload of wadded-up bubble wrap.
    ___________
    * I emailed Vandue Corp, one of the companies that sell full-body Lycra suits, to see if they were aware of having tapped the cadaver apparel market. The customer care person replied that they were not. Though word had reached them that their product had caught on with bank robbers, as the face is covered but allows the wearer (if living) to see out. Presumably the felon, unlike the Halloween revelers and sports fans who more routinely don Lycra suits, wore some clothing over his. Though I hope not. And I further hope he selected the Sock Monkey pattern.
    † Sleeping subway riders, conversely, look exactly like dead men—a fact born out by the regular appearance of news items about commuters who quietly die and then sit, slumped and unnoticed, through several round-trip circuits of the route. As a passenger quoted in “Corpse Rode the No. 1 Train for Hours” attests, “He just looked like he was asleep.”

Fighting by Ear
    The conundrum of military noise

     
    T HE 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). 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.”
    Fallon is lecturing in a classroom at the moment, but after lunch the audiologists in attendance will experience some live-fire simulated combat. Working with the Department of Defense Hearing Center of Excellence, Fallon contracted a company, ArmorCorps, who in turn brought in a team of Marine Corps Special Operations forces, and together they’ve set up a