Photo credit: Rodolfo Quirós
by Daniel Fink, MD, Chair, The Quiet Coalition
A press release from the University of Colorado’s Anschutz Medical Campus reports on assistant professor Nathaniel Greene’s research on noise-induced hearing loss. As the article points out, hearing loss is very common in older people. Almost all over the age of 80 have hearing loss. Hearing loss contributes to social isolation and is also the single largest modifiable risk factor for dementia.
Greene’s work focuses on impulsive noise — sudden, short and high-intensity bursts of sound. Impulsive noise is difficult to study even in the occupational setting, and almost impossible to study in the general public where exposure to impulsive noise is random and often unexpected. The National Institute for Occupational Safety and Health’s recommended exposure limits for occupational noise include impulse noise under average noise exposure limits but impulsive noise may have a disproportionate impact on hearing.
Greene’s work showed that earplug noise reduction ratings underestimate the degree of damage protection against higher-frequency impulsive noise. High frequency hearing is important because consonant sounds that allow us to differentiate words with similar vowel sounds (such as Beer, CHeer, Dear, Fear, Gear and Hear) are in the higher frequency range. This is illustrated by the Speech Banana Audiogram, a tool that can be used to understand sounds we can or can’t hear based on hearing thresholds. I hope Greene’s work leads to better hearing protection devices for impulsive noise.
In the meantime, people should try to avoid impulsive noise exposure. This can be accomplished by crossing to the other side of the street when someone is using a jackhammer or inserting earplugs in anticipation of impulsive noise, like when attending an airshow that might feature a low-level jet flyover.
If something sounds loud, it’s too loud and one’s auditory health is at risk.