Andrew Resnick, Au.D.
Exposure to loud noise is one of the leading causes of hearing loss, and in today’s noise-filled world it is important to understand the potential consequences of noise exposure and how to best protect yourself from damage. Loud sounds can permanently damage the delicate structures of the ear, particularly the sensory cells, known as “hair cells,” found in the cochlea or hearing organ of the inner ear. Hearing loss from loud sounds can occur in one of two ways: acoustic trauma, in which a single exposure to an intense sound damages the ear, and noise-induced hearing loss, in which hearing loss results from repeated exposure to loud sounds over time. Acoustic trauma is typically associated with noise events such as explosions or gunfire; however, sounds we don’t typically think of as “loud” can cause hearing loss if generated very close to the ear – there are even reported cases of a kiss given right at the opening of the ear causing permanent hearing loss.
Noise-induced hearing loss can occur from repeated exposure to sounds that may occur in our everyday lives, depending on our lifestyle: music, firearms, machinery, and power tools are some common examples. The risk of hearing damage from exposure to these sounds depends on both the intensity of the sound and the duration of exposure. For occupational noise, OSHA (the Occupational Safety and Health Administration) allows for workers to be exposed to sound levels of 90 decibels (dB) for an eight-hour day; NIOSH (National Institute of Occupational Safety and Health) recommends no more than 85 dB for eight hours, although their recommendations do not have regulatory force. As the average noise level increases, the allowable exposure time shortens: OSHA regulations state that for every 5 dB increase in the noise level, the allowable exposure time is cut in half, although NIOSH recommendations cut the exposure time in half for each 3 dB increase in intensity.
Music is one of the most common recreational sounds (although occupational for some) that can potentially damage one’s hearing, particularly in today’s plugged-in society. While many recent news stories have focused on the effects of MP3 players on teenagers’ hearing, there has been some debate in the audiological community as to whether these risks may have been somewhat overstated in the popular media.1 Nonetheless, there is little doubt that listening to music through headphones for several hours per day has at least the potential to affect one’s hearing, and the ability of modern technology to allow for more portability, data storage and battery life means that it is easier than ever to spend more and more time with loud music in our ears. Musicians are also at higher risk for hearing loss, and not just those playing amplified music – orchestral musicians are routinely exposed to potentially damaging sound levels.
While exposure to loud sounds may initially result in transient hearing loss, tinnitus and aural fullness, with sufficient exposure the effects on the ear can be permanent. Noise-induced hearing loss typically affects the ability to hear high frequency sounds, particularly those in the 3 – 6 kHz range. This frequently results in communication difficulties in environments with background noise, as well as difficulties hearing soft speech, particularly that of women and children. Excessive noise exposure can also lead to tinnitus, or noise in the ears. While commonly described as ringing, tinnitus can also take the form of hissing, chirping or a number of other sounds. For some, tinnitus is a constant annoyance (or worse), and can interfere with the ability to concentrate and to sleep.
The best ways to protect yourself from the damaging effects of loud noise are to avoid situations with high noise levels, reduce the amount of time you’re exposed, move away from loud noise sources, or turn the volume down on music players. When loud environments are unavoidable, the use of earplugs can be extremely effective in protecting one’s ears. Simple foam earplugs obtained at the local drugstore are an inexpensive way to reduce the sound levels reaching the middle and inner ear. For hunters, electronic earplugs or earmuffs can protect the ears while allowing soft conversation and other environmental sounds to be heard. And for musicians, custom-fit earplugs with special filters allow music to be reduced to safe listening levels while maintaining an even frequency response, thereby preserving the fidelity of the music beyond that afforded by a typical solid earplug.
While it may be difficult in today’s society to avoid loud noise entirely, arm yourself with some knowledge and a good pair of earplugs – your ears will thank you for it.
1 Nemes, Judith. Teen hearing loss study goes viral, experts uncover the facts. Hearing Journal 2011;64(2):19-20, 22-24.