A Review of Gunshot Noise as Factor in Hearing Disorders

Abstract

The impulse noise produced by personal weapons (guns, rifles, shotguns) during military activity, and while people engage in sport, training and hunting, is a threat to the auditory systems of soldiers, civilians, policemen, hunters, forest officers, sportspeople and bystanders not actively engaged in professional or recreational firing. An overview of noise levels generated by different types of weapon is provided, and potential short-term and long-term consequences for the human auditory system are described. The mean values of LC, peak sound pressure level during the shot, at the shooter's ears, for various types of weapons are approximately 160 dB SPL. These are levels that can cause permanent, irreversible negative effects on hearing (hearing loss, tinnitus, etc.) even as a result of a single shot being fired. One of the largest groups of weapon users in Poland (about 120 thousand) are hunters and field masters. They are not obligated by any regulations to protect their auditory systems from impulse noise. This means that this group of firearm users is at particularly high risk of hearing damage. On the basis of the literature review, it is shown that hearing exposure to high-level impulse noise such as a gunshot can result in such consequences as damage to the middle ear and destruction of the outer/inner hair cells in the cochlea. Especially difficult to diagnose is 'hidden hearing loss', i.e. damage to the synaptic connections between the hair cells of the inner ear and the auditory nerve fibres, which is not reflected in the results of basic audiometric testing and can cause hearing problems many years after impulse noise exposure. The wide range of negative consequences of gunfire noise clearly indicates the need for the hearing of the shooters to be protected.