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Risk Management Issues

Hearing is a powerful asset in situations in which an officer might need to communicate or localize sounds. However, officers are exposed to hazardous noise that an compromise their hearing every day. The primary source for this is noise and concussive force from firearm discharges, which damage hearing both in the short term and the long term. In the short term, firearm discharges cause flinch response and momentary disorientation, which can create vulnerabilities in the field. In the long term, firearm discharges will eventually cause tinnitus and hearing loss, even with standard double protection for the ears. In a 10-year study of 20 officers, more than 75 percent reported significant hearing loss as well as tinnitus even while using double protection.

Further, according to a 2003 National Institute for Occupational Safety and Health report, noise levels and concussive force produced by firearms leads to a serious health risk for occupational hearing loss among officers.

WHAT IS BLAST OVERPRESSURE?
The concussive force from an explosion travels on a wave called a shock wave. A shock wave is a front where the leading side is highly positive pressure, or blast overpressure (BOP), and the trailing side is the underpressure. The real danger lies in the instantaneous change of overpressure to underpressure, which doesn’t give the human body time to equalize pressure.

To further clarify, blast overpressure and a shock wave are not the same as sound pressure.

The damaging effects of a sound pressure wave are easily mitigated through commonly used ear protection devices. BOP and shock waves cannot be mitigated through ear protection as both travel right through the body, devastating any cavity organs filled with gas, such as the sinuses, ear canal, lungs and heart. Continued exposure to BOP events will cause a cumulative effect that, over time, will cause damage such as ruptured eardrums, tinnitus, hearing loss, pain, vertigo, stress and heart conditions. Chul-Hee Choi, author of “Mechanisms and Treatment of Blast Induced Hearing Loss,” states in the Korean Journal of Audiology, “The effects of blast on the human body are determined by a variety of factors: distance

“Beyond the human cost of tinnitus and hearing loss, there is a massive financial burden that goes along with hearing disorders. A recent audit of the VA’s treatment facilities found as many as 1.6 million returning veterans are being treated for hearing disorders, more than all other complaints combined.”

from the blast, orientation towards the blast, environmental features resulting in reflection and resonance of the blast wave, power of the blast itself, and patient’s previous trauma history.”

In a comparison study conducted on a 10.5-inch barrel M4 rifle, blast overpressure using an A2 muzzle brake measured at 4 inches from the blast source reached a staggering 12.9 psi.3 The threshold level for rupture of the eardrum is about 5 psi. That could also put the brain at risk; according to
Air Force Lt. Col. Dr. Michael Xydakis, an ear, nose and throat specialist, “The eardrum is only half an inch from the brain, so whatever hits the eardrum is going to hit the brain such as pressurized shock wave.”

awarded officers the equivalent of $212 million to retroactively cover treatments of hearing-related disorders. There is no reason to believe that the U.S. is immune to this kind of litigation.

In 2011, The New York Times published an article on two veteran New York City police officers forced out by a ban on hearing aids. Former officers Daniel Carione and Jim Phillips were forced to retire while using department-issued hearing aids that went against strict NYPD hearing test policy. After a five-year legal battle, Carione was conditionally reinstated to active duty if he could pass a hearing test using the aid. Phillips remained retired from NYPD. Both men were awarded back pay, benefits and seniority for the time they were involuntarily retired. In addition, the city also agreed to make additional payments of $200,000 and pay all legal fees in the case.

COST OF LONG-TERM HEALTH RISKS
Beyond the human cost of tinnitus and hearing loss, there is a massive financial burden that goes along with hearing disorders. A recent audit of the VA’s treatment facilities found as many as 1.6 million returning veterans are being treated for hearing disorders, more than all other complaints combined. The cost of giving basic care for these hearing disabilities, according to a 2010 report, is a staggering $1.4 billion. A recent report also relates a three-fold spike in compensation cases for ex-Royal Canadian Mounted Police to a rise in hearing-related complaints. Unsurprisingly, the VAs in both the U.S. and Canada ranked tinnitus, hearing loss and PTSD as the top conditions they treat.

In addition, a recent settlement in the U.K.

WHY THE SEVERE RISE IN HEARING LOSS?

Why, when gun ranges are increasingly requiring double protection and using advanced acoustical dampening techniques, are instances of tinnitus and hearing loss at an all-time high?4 The reason most likely lies in the department-issued firearm and implementation of that firearm. While the previously common pistol and shotgun fire subsonic rounds with relatively low BOP and no shock wave, officers today are required to implement high-powered rifles firing supersonic rounds, inducing shockwaves and a much greater BOP. Increasingly, the M4 rifle with a standard A2 muzzle brake (MB) is the rifle of choice for the majority of law enforcement departments and officers in the United States — a firearm with a supersonic round that induces a shock wave and has a massive amount of BOP.

In addition, because officers are frequently training and operating in close quarters, the M4 rifle with an A2 MB is one with a shortened barrel length. Shortening the barrel further increases the BOP in addition to having the explosion and shock wave closer to the officer’s head and body, significantly increasing damaging effects. As an officer or user of the M4 rifle with an A2 MB, think about the last time you were out on the range practicing your shooting skills. You most likely used eye protection and at least one set of ear protection, likely ear muffs or ear plugs. After only a couple hours of training with your personal protective equipment (PPE) on, why think about the last time you were out on the range practicing your shooting skills. You most likely used eye protection and at least one set of ear protection, likely ear muffs or ear plugs. After only a couple hours of training with your personal protective equipment (PPE) on, why is it that you walk away from training with a headache, migraine or shooter’s fatigue? Even worse, what if you still had to go on duty after training with those same symptoms? Would you be 100 percent effective while on duty? Department leaders implementing rifle suppressors to reduce the effects of blast overpressure and noise on their officers. While suppressors, when combined with PPE, are the best solution to this inherent problem plaguing our law enforcement communities, they have some drawbacks. First, rifle suppressors are classified and regulated by the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF), in accordance with the National Firearms Act, as a Class 3 product requiring an occupational tax stamp of $200 per unit. While the tax is waived for law enforcement purchase, Class 3 product purchases are still subject to a processing lead time for purchase approval from the ATF that can average four to six months, or longer. Second, rifle suppressors have a stigma among many U.S. communities as a tool specifically geared for the military, invoking images of spies and assassins who use them for killing. While suppressors are ideal for the hearing health of our officers, many departments forbid their use due to the image they want to portray to their communities. As crazy as this sounds, this is really affecting the livelihood of our police officers.

Third, rifle suppressors come with a high cost. Suppressor prices range from $800 to $1,600 and the majority of departments simply do not have the budget for them unless they are only outfitting their SWAT/ERT team, which may leave other officers unprotected. While some departments can find deals on lower cost suppressors, lower cost usually comes with lower quality, lower durability and fewer added features. Like anything in retail, you get what you pay for. This eventually leads to dissatisfaction with the product, which then leads to tactical teams reverting back to conventional A2 MBs. Lastly, from the tactical perspective, rifle suppressors make the rifle longer and heavier with an off-set center of gravity, such as forward

Stigma Surrounding Suppressors

  • Suppressors are classified and regulated by the Bureau of Alcohol, Tabaco, and Firearms (ATF) by National Firearms Act (NFA) as Class 3 product. ‘
  • Class 3 product purchases can be subject to a processing lead time for purchase approval from the ATF which can average 4 to 6 months, or longer.
  • Suppressors have a stigma among many US communities as a tool specifically geared for the military, invoking images of spies and assassins who use them for killing.
  • Suppressors are expensive. Suppressor prices range from $800 to $1,600 and the majority of departments do not have the budget for them.
  • Suppressors add additional length which offsets the rifle’s center of gravity making rifles long and forward heavy.
  • Suppressors can compromise firearm reliability due to the increased back pressure and by causing more carbon to blow back into the rifle’s receiver. •
  • Suppressors compromise point-of-aim and point-of-impact requiring additional hours of training, depending on the manufacturer and assembly.

“When is the best solution not really the best solution? When it is too highly regulated, holds a negative stigma, and is too expensive and unwieldy to really solve the problem. The suppressor is all of these things, so another solution is clearly needed.”

heavy. In addition, reliability is compromised due to the increased back pressure suppressors have on rifles. Furthermore, point-of-aim and point-of-impact are also altered because suppressors change the harmonic design of the M4 rifle barrel, causing shot groupings to be larger in diameter.

When is the best solution not really the best solution? When it is too highly regulated, holds a negative stigma, and is too expensive and unwieldy to really solve the problem. The suppressor is all of these things, so another solution is clearly needed.

to manage blast overpressure with a less expensive, easy-to-use device that marries the effectiveness of a suppressor without the stigma attached to using one. Implementing this kind of device means that officers will be able to function better in training and in combat by reducing the flinch response and disorientation that blast overpressure causes, leading to better accuracy, time on target and tighter grouping as well as seeing a pronounced reduction in shooter’s fatigue.

ABOUT THE AUTHOR

Keith Mercer is a freelance writer and editor who resides in Winter Park, Florida. He has written a number of technical documents and articles covering firearms and health-related subjects.
The author acknowledges Sergie A. Albino of IROC Tactical for his assistance in preparing this article.

ENDNOTES

  1. Dept. of Otolaryngology, National Taiwan University Hospital, Taipei, Taiwan.
  2. RCMP Disability Claim Forecast
  3. U.S. Dept. of Veterans’ Affairs, Veterans’ Compensation, Most Prevalent Disabilities of all Compensation Recipients, 2013, p. 30.
  4. IROC Tactical, Blast Overpressure Study, Feb. 22, 2016.