Combined effects of noise and temperature on human comfort and performance

This paper summarizes results from an experiment designed to investigate the combined effects of noise and temperature on human thermal comfort and task performance. Thirty subjects (16 females, 14 males) were exposed to all combinations of five thermal conditions (PMV +1 [79.6°F:26.4°C], PMV +0.5 [75.8°F:24.3°C], PMV 0 [72.1°F:22.3°C], PMV -0.5 [68.3°F:20.2°C], and PMV -1 [64.6°F:18.1°C]), three RC noise levels (RC-30, RC-40, and RC-50), and two sound qualities (neutral and rumbly): all sounds mimickednoisefrombuildingventilationsystems. After a one-hour adaptation period at each condition, subjects rated their thermal comfort using the ASHRAE Thermal Comfort Scale and the Tenant Survey Questionnaire, and then completed typing and number-checking tasks. There were no statistically significant effects of thermal condition, RC level, or sound quality on performance of the typing or number-checking tasks. Statistical analyses showed that thermal comfort was affected by RC noise level, while ratings of building or office noise were not affected by the ambient temperature. There were also differences in the way males and females experienced the thermal and acoustical environments. Females rated lower temperatures colder than males, and higher temperatures more pleasant than males: thermal comfort composite ratings from males and females converged at about 72°F (22°C).