Although scientists and doctors believed, for many years, that noise was only a problem if it was loud enough to damage hearing, there is now increasing evidence that exposure to relatively low noise for long periods can affect people's health in various ways. For example, it can disrupt cognitive development in children, disturb sleep, help to cause psychiatric disorders, and raise blood pressure. Although governments still fail to recognise such noise as a health hazard, the World Health Organisation (WHO) has revised its guidelines on safe noise levels in the light of new research; the new guidelines are due to be published in 1997. They reduce the recommended average noise level, suitable for undisturbed sleep, from 35dB(A) to 30dB(A), and also include a peak night-time maximum of to 45dB(A). The WHO report's editor urges governments to adopt its recommendations, using the precautionary principle; they should give special consideration to children and to those who are most sensitive to noise. The article outlines several specific studies, providing evidence of stress among children living near international airports, and linking long-term exposure to traffic noise with blood pressure rise. While tougher controls should make noisy areas quieter, the number of really quiet places continues to decrease.
Samenvatting