The noisiest restaurants are so loud they may be damaging the hearing of waiters and other workers who put in full shifts during the dinnertime rush, according to a study from researchers at the University of California, San Francisco. Although diners are not at risk for hearing loss, the researchers said restaurant reviewers should advise the public about noise levels in restaurants.
Many factors can make a restaurant noisier. Hard surfaces, high ceilings, open kitchens, and large crowds all can contribute to a cacophony that makes simple conversation a struggle. According to Robert Sweetow, PhD, director of the audiology clinic at UCSF, noise in restaurants is one of the most common complaints among diners, particularly those with sensitive ears and hearing problems.
For the report published in the May issue of Audiology Today, Sweetow and Lisa Tate, MS, a UCSF staff audiologist, measured sound levels in five restaurants, ranging from a quiet bistro to a very noisy restaurant/bar. Visiting on Thursday, Friday, or Saturday evenings between 6 pm and 10 pm, the researchers took sound readings for several one-hour blocks of time over the three-day period. They recorded weighted maximum noise levels, and also calculated the average noise exposure a waiter or other worker might get over an 8-hour period.
The maximum noise levels ranged from 85.5 decibels (dBA) - about as noisy as heavy city traffic - to 109 dBA equivalent to a loud dance club. When averaged over eight hours, the exposures ranged from 50.5 dBA to 90 dBA. Continued exposure to noise at 85 dBA or higher eventually can cause hearing loss, according to standards set by the National Institute for Occupational Safety and Health. The institute has also advised that, if a workplace exceeds that noise level, the employer should take steps to reduce noise or protect the workers' hearing. Two restaurants in Sweetow's survey exceeded this limit. The solution, Sweetow said, is to educate the public through noise ratings for restaurants, such as the system that the San Francisco Chronicle has incorporated into its restaurant reviews. The system rates a restaurant with one bell through four bells, or uses a bomb symbol if the noise exceeds 80 decibels. Sweetow urged other newspapers to institute similar ratings to allow patrons to select a quiet restaurant if they wish, and allow waiters and other workers to know whether their workplace might be damaging their hearing. "A diner in a restaurant is not at risk for permanent hearing loss, but people have a right to know what kind of environment they're walking into," he emphasized.