Quantitative model of combined annoyance caused by simultaneous exposure to outdoor traffic sounds

Laboratory experiments which include the simulation of simultaneous exposure to the multiple traffic sounds and the assessment of subjective annoyance have been used to study the interaction between the noise sources, it’s influence on overall annoyance, and the modeling of exposure-response relationships. The aircraft (or railway) noise annoyance is masked by road-traffic noise and the higher levels the road-traffic noise has, the lower aircraft (or railway) annoyance the subject rates. For combined noise which two sources have similar sound levels or equally annoying levels, the overall annoyance is higher than the maximum source-specific annoyance, while, for combined noise in which the level of one source was 10 dB or higher than that of the other, the overall annoyance was equal to the maximum source-specific annoyance. An annoyance model for a combined noise exposure was developed using a weighted summation method, and the integration of noise perception resembles the summation of the acoustic pressure of each source.