DO WE MEASURE DAMAGING NOISE CORRECTLY?

Measurement and analysis of several industrial noises, for determining the risk of hearing loss due to noise, revealed significant peaks of short duration especially in the environment of the iron and steel industry. Since these peaks contain significant amounts of energy in the frequency region 4 - 6 kHz and also because these frequencies are amplified in the outer and middle ear it explains why hearing loss always starts around 4 - 6 kHz and also why the risk of hearing loss is considerably higher in this case than that given by the total noise dose criterion. Finally, a rather simple method has been proposed for setting the limits for risk criteria taking into consideration the total noise dose as well as the impulsive content of the noise.