Abstract:

A standard on Occupational Hearing Loss, ANSI S3.44 (1996), has been recently published. One of its features, unlike ISO R-1999 upon which it is based, allows a trading rule other than one based solely on equal energy. To account for the fact that intermittent noise, as compared to steady noise of the same energy, may not be as harmful to hearing, equal energy with a correction factor is being investigated. ANSI Working Group S3-58 is evaluating at least seven different approaches. In order to evaluate the best approach for correcting for intermittency, W. Dixon Ward's temporary threshold shift (TTS) data, from a variety of intermittent noise exposures [W. D. Ward, Effects of Noise on Hearing (Raven, New York, 1976), pp. 407--420], will serve as one evaluation criterion. Actual hearing loss data from exposures to various intermittent noises will serve as the other evaluation criterion.