Research progress on the acoustic environments of healthy buildings

Building and urban acoustic environments greatly contribute to the quality of healthy buildings. This paper first discusses the developmental transitions from noise control to soundscape construction, and the changing focus from negative effects on public health to the promotion of health benefits. During this transition, the impacts of acoustic environments on human health have been investigated from various research perspectives, from concept to theory to methods. In current soundscape research, sound environment designs are based on health concepts. Innovative results have been introduced from this focus. First, the impacts of soundscape perception on human health and the psychophysiological effects of soundscape have been extensively reviewed. Reduced negative soundscapes are significantly positively correlated with the self-reported health conditions of subjects. Especially, soundscapes reported as positive (e.g., pleasant and calm) are significantly positively correlated with environmental stress restoration. The physiology and neurophysiology of soundscapes are emerging subjects that require extensive further research. Research on the restorative effects of urban public open spaces has included the development of relevant theories and practice, experimental studies of restorative performance and its influencing factors, and sensitivity studies, which measure the response magnitude of physiological indicators to typical soundscapes. The restorative quality of public open spaces in the urban context is of particular interests. Soundscapes in public open spaces are known to directly affect the psychology, physiology, and attention span of individuals. They also exert an indirect recovery effect through audio-visual interactions. A study on the sensitivity study of physiological indicators analyzed the change of the physiological signals over time, the type of scenery, and the restoration effect was quantified from the relationships among different subjective scales. Stressed children exposed to different potentially restorative soundscapes perceive the restorative sound scenery differently from adults. The effect of noise on the cognitive performance of children is primarily reflected in the degree of subjective annoyance, and children’s test performances do not significantly depend on the varying noise conditions. In specific spaces such as hospitals, the acoustic environment is known to affect inpatient health and the efficiency of hospital staff. Studies have confirmed that improving the acoustic environment benefits the resting ability, sleep, and mood of inpatients, and this can also improve the efficiency of hospital staff. With the broadening and deepening of acoustic environment research and the effective development of research tools, indicator systems and research paradigms will become more standardized. Such standardization will further deepen the research and lead to evaluative standards. Much scope remains for investigating the impact mechanism and efficiency of various soundscape restorative treatments in urban public open spaces. Furthermore, the health effects of soundscape treatments for other specific groups of people and other specific spaces should be elucidated. Finally, research should move from revealing the influence patterns and tendencies of soundscapes toward the active design of healthy acoustic environments.