The effect of noise exposure on sleep quality of urban residents: A comparative study in Shanghai, China

Noise exposure is becoming extremely common in urban area, but its specific impact on sleep remains controversial. Considering the limitations of previous researches, a field study which can conduct both horizontal and longitudinal analysis was designed. Urban participants were tested during two weeks in their homes, and the noise level of bedroom was artificially regulated by changing the status of window and door. During the 1050 test nights in 75 households, noise exposure was reflected from both instrument monitoring at night and perception questionnaire in the morning, and sleep quality was accessed from actigraphy and questionnaire. The analysis results showed that, 92.3% of the bedroom acoustic environment did not meet the minimum requirements of Chinese standards, and 87.9% of subjects had ever experienced harmful noise during the test period. Furthermore, sleep quality was affected by noise exposure from the perspective of both physiological and psychological; the duration of rapid eye movement (REM) sleep was significantly (p < 0.05) shortened with the increase of sound intensity, the duration of deep sleep shortened and subjective sleep quality worsened significantly (p < 0.05) with the increase of acoustic sensation vote. In addition, females were more sensitive to noise exposure and their subjective sleep quality was more likely to be influenced by emotions. This study has important implications for acoustic environment design of bedrooms in cities, and suggested more attention should be paid to the anxiety caused by noise exposure.