Masking effect of water sound on road and rail traffic noises in office soundscape

This study represents a laboratory experiment focusing on the effect of water sound on masking traffic noises in an office soundscape. Subjective evaluations and physiological responses of thirty-two participants exposed to the combination of water sound and traffic noises were measured. Silence and pure traffic noises were used as the reference conditions. Significant masking effects of water sound were observed on both the subjective evaluation of the sound environment and the physiological responses to traffic noises. To improve the subjective evaluation of the sound environment, the water sound was found to have stronger masking effect on rail traffic noises than the road traffic noise. To reduce the noise annoyance, SNRs at -3dB and 3dB was found to be the most effective for the conventional train noise and the high-speed train noise, respectively. Water sound at low sound level (SNR=-3dB) was also found to be effective in improving the acoustic comfort for the conventional train noise. Effect of water sound in masking the physiological impact of traffic sounds was found to be limited which depended on the traffic noise type and participants characteristics. Comparing to EDA, HR were found to be more easily affected by the water sound.