Association of work-related accidents with noise exposure in the workplace and noise-induced hearing loss based on the experience of some 240,000 person-years of observation

This retrospective study explores the association between occupational noise exposure at the time of hearing tests, permanent noise-induced hearing loss and work-related accident risk. Log-binomial analysis was used to first ascertain the association between study variables according to activity sector (North American Industry Classification System, NAICS) and accident context while controlling for age. Second part of the paper estimates the overall number of accidents attributable to occupational noise or the associated hearing loss (excess fraction). Study was carried on a sample of 52,982 male workers exposed to a minimum of 80dBA on a daily basis and whose hearing was examined at least once between 1983 and 1996 by public health authorities of Quebec. These participants evidenced bilateral average hearing threshold levels at 3, 4 and 6kHz ranging from normal (/=90dBA) and noise-induced hearing loss.