Noisy workplaces can make workers deaf

March 10, 2009

The majority of the 650,000 employees from Quebec's manufacturing sector - specifically those working in metallurgy and sawmilling - are exposed to noise levels that exceed governmental norms.

According to a new study from the Université de Montréal, the Université Laval and the Institut national de santé publique du Québec, extra workplace decibels increase the risks of both work-related accidents and road collisions. The findings will be reported in three journals: Occupation Environmental Medicine, Accident Analysis and Prevention and Traffic Injury Prevention.

The researchers studied a sample of 53,000 workers. "More than 60 percent were exposed to noises exceeding the norm of 90 decibels (dB) per day, which is equivalent to the sounds that emanate when a subway enters a station," says Michel Picard, a professor at the Université de Montréal's School of Speech Therapy and Audiology, who conducted the study along with his colleague Tony Leroux.

Quebec has not revised its workplace noise norms in close to 40 years. Throughout North America, including other Canadian provinces, the norm is set at 85 dB. This is a clear indication that Quebec is lax when it comes to noise in the work environment.

When a worker is exposed to noise exceeding 90 dB during a day's work, that worker is 6.2 percent more likely to have a work accident than colleagues working in the same environment with less noise. If the worker suffers hearing loss, his risk of injury is 7 percent greater.

Out of 43,250 reported work accidents, 5,287 were associated to noise. "What is particularly worrying is the young age of the workers," says Picard. The average individual was a 36-year-old male exposed to the noise for 13 years. And these hearing losses are permanent.

The researchers also focused on the driving records of workers exposed to noise in the workplace. By cross-referencing with data from the Société de l'assurance automobile du Québec they analyzed 46,000 men who were exposed to more than 100dB in their workplace.

The risk of an accident increases by 6 percent for those who still have good hearing. However, the risk increases to 31 percent for workers who suffered important hearing losses. These are not minor car accidents, but serious collisions.

According to Picard, this new study clearly indicates that workplace noise levels are a problem neglected by authorities. "Technology exists to reduce noise in the workplace," stressesPicard. "All that's missing is the political will."

Source: University of Montreal