Maximum noise levels as indicators of biological effects

The equal energy concept does not meet the requirement for a biologically relevant model for noise exposure and the extent of annoyance due to noise dose is determined independently by the level from the noisiest events and the number of events up to a certain saturation point.

Abstract

The biological response to noise is reviewed with reference to average stimulus levels integrated over time, maximum stimulus levels and the number of stimuli. It is concluded that the equal energy concept does not meet the requirement for a biologically relevant model for noise exposure. Annoyance data from noise from aircraft, road traffic, trains and laboratory experiments is used to examine this hypothesis. It is concluded that the extent of annoyance due to noise dose is determined independently by the level from the noisiest events and the number of events up to a certain saturation point, above which a further increase in number does not influence the annoyance. Further research work should be undertaken to identify this number of events for different environmental noises and to clarify how the maximum noise level should be defined, particularly for road traffic noise.