Tag Archive: Journal of the Acoustical Society of America

Hearing loss from recreational sound exposure

Photo credit: Brett Sayles from Pexels

by Daniel Fink, MD, Chair, The Quiet Coalition

RECOMMENDATIONS TO REDUCE HEARING LOSS FROM RECREATIONAL SOUND EXPOSURE

This detailed review article by Richard Neitzel, PhD, and Brian Fligor, PhD, in the Journal of the Acoustical Society of America discusses the risk of noise-induced hearing loss from recreational sound exposure.

The abstract contains the important conclusions, which are amply supported by the article itself. They are:

  1. The recommended occupational exposure limit is 85 A-weighted decibels (dBA)*. Some exposed workers will develop hearing loss from this noise exposure. To eliminate the risk of hearing loss, a 24 hour average of 70 dB is recommended.
  2. It is possible that occupational noise exposure may have worse impacts on hearing than equal exposures to recreational noise. But the application of statistical hearing loss models developed from occupational noise data to estimate the impacts of recreational noise exposure is nevertheless warranted.
  3. A recreational noise exposure limit of 80 dBA for 8 hours, equivalent to 75 dBA for 24 hours, should prevent hearing loss for adults. For children and other vulnerable individuals, e.g., those who already have hearing loss, the lower exposure level of 75 dBA for 8 hours, or 70 dBA for 24 hours, is appropriate.

Common non-occupational noise exposure sources include public transit, appliances, power tools, personal music players and other personal listening devices, musical instrument practice and performance, concerts, sports events, and parties.

Protecting hearing is simple. Eliminate high noise exposures where possible, increase the distance between you and noise sources around you, and use hearing protection (earplugs or ear muffs).

Because if something sounds too loud, it is too loud, and your hearing is at risk.

*A-weighting adjusts noise measurements for the frequencies heard in human speech.
Dr. Daniel Fink is a leading noise activist based in the Los Angeles area. He is the founding chair of The Quiet Coalition, an organization of science, health, and legal professionals concerned about the impacts of noise on health, environment, learning, productivity, and quality of life in America. Dr Fink also is the interim chair of Quiet Communities’ Health Advisory Council, and he served on the board of the American Tinnitus Association from 2015-2018.

A fascinating study about restaurant noise

Photo credit: rawpixel.com from Pexels

by Daniel Fink, MD, Chair, The Quiet Coalition

Restaurant noise is a problem for patrons trying to converse with their dining companions, and a common complaint in the Zagat survey.

When ambient noise is loud, people raise their voices to increase the speech to noise or signal to noise ratio to help others hear what they are saying. This creates a positive feedback loop, where everyone increases how loud they are speaking, until it’s so loud that no one can understand anything being said. The phenomenon, called the Lombard effect or cocktail party effect, has been known for a long time.

This study in the world’s most prestigious acoustical journal, the Journal of the Acoustical Society of America, adds to our knowledge of how restaurant noise affects understanding of speech. The researchers studied speech in a sound booth at different ambient noise levels. The sound level of speech increased as ambient noise increased. Subjects reported disturbance of speech beginning at 52.2 A-weighted decibels (dBA), with vocal effort beginning to increase at 57.3 dBA. The researchers noted that as background noise increased, it triggered a decrease in the willingness to spend time and money in a restaurant. The researchers concluded that restaurants should have ambient noise levels of 50-55 dBA. That’s a much lower sound level than that in most restaurants.

The study is quite technical, and I have two quibbles with it.

First, it was done in a sound booth. That is ideal for research, but I would be interested to see the study replicated in a real or simulated restaurant environment.

Second, the average age of the subjects was 21, with a range from 18-28. I would like to see the study repeated, even with the same methods, in a population age 58-68, with an average age of 61, or even 68-78, with an average age of 71.

I suspect the findings would be similar, but the decibel numbers would be significantly lower.

Dr. Daniel Fink is a leading noise activist based in the Los Angeles area. He is the founding chair of The Quiet Coalition, an organization of science, health, and legal professionals concerned about the impacts of noise on health, environment, learning, productivity, and quality of life in America. Dr Fink also is the interim chair of Quiet Communities’ Health Advisory Council, and he served on the board of the American Tinnitus Association from 2015-2018.