A field study on indoor environment quality of Chinese inpatient buildings in a hot and humid region.

ABSTRACT

In this research, objective physical measurements and subjective questionnaire surveys are used to investigate the indoor environment quality of Chinese inpatient buildings. The relative humidity in the inpatient buildings reaches 65%-75% during summer, resulting in the regular appearance of microbial growth on indoor surfaces. The average outdoor air change rate measured through the CO2 concentration decay method in the sampled inpatient rooms is 1.1 h-1, which is 45% below the standard threshold. The CO2 concentration in over 99% of the functional spaces is below the threshold of 1000 ppm. However, the dissatisfaction rate of the air freshness is higher than 25%, owing to the characteristics of healthcare activities. Insufficient fresh air volume and high supply air humidity ratio of the outdoor air system result in the inadequate dehumidification capacity and the over-humid environment in the inpatient buildings. From the perspective of indoor TVOC and PM2.5 concentration, a hospitable IAQ is achieved in the inpatient buildings. In the nurse unit, the illumination levels in public areas, such as patient corridors and nurse stations, are inadequate. The average noise levels (A) in the inpatient rooms and nurse stations are 50.7 and 61.6 dB, respectively, which exceeds the Chinese standard. According to the subjective survey, the dissatisfaction rates of overall IEQ in the summer for patients and visitors are 7.9% and 10.4%, respectively, while for staff it is 34.8%. Statistical analysis reveals that the satisfaction levels of the patient with the IEQ are higher than that of the visitor and staff.