ASA 125th Meeting Ottawa 1993 May

5aNS4. The importance of memory when predicting annoyance on the basis of equal energy.

George A. Luz

US Army Environmental Hygiene Agency, Aberdeen Proving Ground, MD 21010-5422

In 1981, CHABA published a report showing the annoyance for a 24-h day--night average sound level from sonic booms/blasts (measured with C) to increase at a faster rate than that from transportation noise (measured with A). In 1979, Luz and Lewis presented a theoretical argument that this difference was due to a difference in the loudness functions for the different noise sources. In 1992, Schomer et al. provided experimental proof for these differing loudness functions. A radical implication of Schomer et al.'s demonstration is that the equal energy rule is inappropriate for the assessment of heavy weapons noise and other types of explosions. A more conservative approach is that the equal energy rule is a description of human memory for the annoyance of noise. Using examples from past studies, an attempt is made to define the limits over which memory can be expected to conform to the equal energy rule.