Hearing is critical to the performance of NATO forces and is integral to situational awareness and verbal communications. Noise Induced Hearing Loss (NIHL) is commonly caused by exposure to excessive noise levels in the military environment, and can cause irreversible damage. Regular exposure to over 85 decibels (db) can cause hearing damage such as tinnitus, and exposure to extremely loud noise that exceeds 120 db can increase the risk of sudden or immediate hearing loss. Harmful noise levels do not always cause pain, so more often than not there is no immediate reaction, yet when an individual does realize their hearing is impaired (e.g. sounds become muffled or distorted) it can be too late to intervene. On a personal level, auditory dysfunction impacts on safety, career progression and quality of life. Such an impairment will reduce military effectiveness and increase costs for rehabilitation and compensation.
A European Directive has set limits to protect personnel from the risks caused by noise. The level at which employers must provide hearing protection and hearing protection zones is now 85 dbs (daily or weekly average exposure) and the level at which employers must assess the risk to worker’s health and provide them with information and training is now 80 dbs. There is also an exposure limit value of 87 dbs, taking account of any reduction in exposure provided by hearing protection, above which workers must not be exposed. The Ministry of Defence, as an employer, has a legal obligation to adhere to this directive (outside the level of front line combat) and must take reasonable steps to provide suitable hearing protection.
Members of the Armed Forces within NATO, are at particular risk of NIHL; peak exposure levels from jet engines can reach over 140 db, and that from a gunshot (“impulsive” noise) can reach 200 db. The auditory system is particularly susceptible to damage from noise and blast exposure, and indeed the incidence of combat-related hearing loss and tinnitus is high. As at November 1, 2103 there were 156,220 UK Armed Forces personnel that had impaired or poor hearing recorded on their medical record. Also it has been reported that Veterans under the age of 75 are 3.5 times more likely than the general population to report problems with their hearing. There is therefore a need to review the recent NIHL research and identify the challenges and future research needed to address this problem
a) prevalence of NIHL – nature and evolution of Service-related NIHL.
b) Assessments used to assess hearing function/early detection of NIHL/use of online hearing checks (current national practices and identifying best practice).
c) individual susceptibility to NIHL, risk-taking behavior/peer pressure.
d) assessment of noise exposure and identification of those most at risk.
e) review of the current thresholds and hearing protection measures in place to identify any capability gaps.
f) Identification of effective hearing loss prevention strategies (e.g. use of sophisticated, customisable hearing protection, training and education on NIHL).
g) Sharing and technology watch for novel means of monitoring, preventing and treating NIHL.