Instruments for measuring noise are described, including sound level meters, calibrators, impulse meters, frequency analyzers, accessory equipment, and sound monitors. Sound exposure monitors can be worn by roving workmen to record individual patterns of exposure. Criteria for the acceptability of noise are dictated by the effects which are to be avoided. The most important of these is hearing damage resulting from prolonged exposure to excessive noise. Other undesirable effects are speech interference, annoyance, and non- auditory effects of noise. Survey techniques are described.
The Industrial Environment - Its Evaluation and Control, NIOSH, Cincinnati, Ohio, Chapter 25