Sound levels recorded within the symphony orchestra and risk criteria for hearing loss

Investigations into noise-induced hearing loss should consist of two parts: a mapping of the sound environment and a charting of hearing loss. This paper is the first part of such an investigation: a mapping of sound levels and sound spectra within the symphony orchestra. It was found that 'heavy' symphonic music exceeds the permitted dose for industrial noise equivalent to 85 dB(A) for a full working week. The permitted noise dose is reached for 'heavy' music after a working time of 10 hours per week in 'exposed' positions, such as in front of trumpets, and after 25 hours in 'normal' positions. A simple method to estimate the 'noise' exposure in equivalent sound level for combination of different sorts of music has been developed.