抄録
The application of Leq as a measure of loudness of various noises is investigated. Nine kinds of noise sources, -aircraft noise, super express train noise, train noise, road traffic noise, speech, music, impulsive noise, artificial level-fluctuating noise and steady state noise-are used as stimuli. The duration is about10sec except for impulsive noise. Four kind levels are used in each noise source, therefore36stimuli are contained in a stimulus series. They are presented in random order and their loudness are judged by magnitude estimation. As a result of experiment, it is found that Leq can be used as a good measure of the loudness of various noises as a first approximation. Strictly speaking, however, there is a slight, but systematical deviation from Leq in PSE's of some noise sources. This fact suggests that it is necessary to add some factors to Leq in order to decide the permissible levels of these noise sources.