Noise at the workplace and upcoming demands to the acoustic environment
Søren Peter Lund, Nat. Inst. Occup. Health, Denmark

The regulation of noise exposure in the working environment has previously been centred on preventing noise induced hearing loss, but more recently other effects of noise exposure have come into focus. Concern that noise may lead to stress, effects of the cardiovascular system and increase the risk of ischemic heart disease has not been sufficiently substantiated. Noise may indeed cause annoyance and distraction, and may lead to reductions in health and loss of quality of life. The measurement of noise as the average sound pressure level over time (LAeq) seems inadequate to estimate the noise induced annoyance and distraction, and several other factors has to be considered. The non-auditive effects of noise arises through interaction between the physical parameters of the noise (sound level, frequency, fluctuations, meaning, room acoustics, etc), psycho-social context at work (lack of control, lack of predictability, lack of meaning, cognitive demands, etc.), and individual factors (hearing ability, personal resources, etc.). The complexity of the interaction makes it difficult to generalise from one area to another, but certain areas can be identified from the complaints of noise several. Among the groups with complaining of high levels of noise are schoolteachers and employees in children’s day care institutions and open offices. The levels of noise in these areas are different, but seems to be characterised by low acoustical quality, high psychosocial stress levels, and employees towards the end of their carrier. The change of the work towards more cognitive tasks, the ability to communicate together with an expected increase of the number of years as active before retirement seems to emphasize on the demands of improvement of the acoustical environment at the workplace. The demands will further increase if the notion that the young at the start of their carrier have worse hearing than previously.