Tinnitus and hearing loss are the two most common disabling factors for US veterans – most likely due to our soldiers’ excess exposure to loud noise during training and combat. Whether on the battlefield or at a rock concert, noise induced hearing loss (NIHL) is 100% preventable. Because of this, the Department of Defense is working diligently to collect data in order to better protect the hearing of military personnel.
Current NIOSH Occupational Noise Exposure Limits
The National Institute for Occupational Safety and Health (NIOSH) has set forth guidelines that determine the amount of noise exposure that is safe for an employee to endure during their workday (including Department of Defense employees). These guidelines do not monitor noise exposure outside of work and “assume” the employee participates in quiet activities both when off-duty and on the weekends.
For a member of staff working an eight-hour workday, five days a week, NIOSH recommends noise levels at no higher than 85 decibels (dBA). 85 dBA is about as loud as a garbage disposal (http://www.industrialnoisecontrol.com/comparative-noise-examples.htm). For workplaces with sound levels that are higher than this, there are stricter regulations. For every increase of only three decibels, the exposure time limit is slashed in half. This means that for workplaces that ring in at 88 dBA (about the sound of a food blender) employees may only be exposed for four hours per day, 91 dBA just two hours, 94 dBA one hour, and so on and so forth.
Noise Exposure in the Military: An Around the Clock Concern
It is not difficult to see how an average military training facility or basecamp will ring in at noise levels much higher than this. Military personnel are typically exposed at all hours of the day – not just the typical 8-hour workday of a civilian.
According to health.mil (https://www.health.mil/News/Articles/2018/09/20/Noise-impact-on-hearing-loss), the official website of the Military Health System, noise exposure can be a 24/7 issue in all branches of the armed forces. For example, off-duty members of the Air Force are often exposed to noise measurements in the berthing areas of aircraft carriers that exceed hearing protection standards. This exposure is in addition to occupational noise when on-duty. More research is needed to determine the level at which members of the military experience dangerous noise levels when off-duty. On top of research, it is imperative that the Department of Defense work to alleviate this noise exposure and provide better protections to personnel.
Department of Defense Research on Noise
The Navy In-House Laboratory Independent Research Program has been studying the effects of noise exposure during the recovery time of Navy sailors. This research simulated the elevated steady noise levels that would be present on an off-duty shipboard. These are very similar to the sounds an average sailor would hear during personal time aboard a Navy ship. These noises were in addition to the an 8-hour workday at the 85 dBA exposure limit set forth by NIOSH. Although the off-duty noise exposures would not be dangerous on their own, when combined with on-duty noise exposures there was risk for permanent hearing loss after just four weeks (https://www.health.mil/News/Articles/2018/09/20/Noise-impact-on-hearing-loss).
Noise Exposure Combined with Inhaled Chemicals
To complicate matters of noise exposure for the military, the inhalation of chemicals may worsen noise induced hearing loss. Members of the Air Force are consistently exposed to a certain chemical found in jet fuel called volatile organic compounds (VOCs). VOCs are known to impact hearing health, although the exact connection between these are currently unknown.
It is important that the Department of Defense continue to study the effects of noise exposure for both on and off-duty military personnel. The Naval Medical Research Unit out of Dayton Ohio (NAMRU-Dayton) is currently developing a system that can study steady and impulse noises for 24 hours a day. This system will also be able to simulate and study chemical exposure during some of all of that time as well. Hopefully this research will lead the military to implement more protective measures to protect the hearing health of our valued soldiers.
Visit Us at Hearing Wellness Solutions
Whether you are a veteran or a civilian, exposure to loud noises has a detrimental effect on your hearing. Are you concerned about your hearing abilities? Contact us at Hearing Wellness Solutions for a comprehensive hearing exam and to learn more about healthy hearing practices.