Operating behavior and corresponding performance of portable air cleaners in residential buildings, China

Abstract

Portable air cleaner is more and more widely used in residential buildings in China due to the serious ambient air pollution in recent years. However, its performance on improving the general indoor air quality is not only dependent on the efficiency of the device, but also influenced by how occupants use it. The objective of this study was to investigate occupants' behavior and its corresponding performance of portable air cleaner in improving indoor air quality in residential buildings in China, using methodology of questionnaire survey and field measurement. A sample of 43 residential buildings equipped with portable air cleaners were selected from eight cities over China for the investigation during June 2017 to December 2017. The usage time, running airflow, and indoor PM2.5 concentrations were monitored continuously. The continuous monitor of power usage showed about 81.4% of the investigated occupants did not use their air cleaners at all. Among the occupants who intermittently operated portable air cleaners (18.6%), the average operating time was only about 1–4 h on the days they used the device, and usually ran at low and medium airflow mode. With such operation behaviors, the air cleaner could not significantly improve the indoor air quality indicating by the PM2.5 concentration level, although the efficiency of the air cleaner is high enough to reduce the pollutant level if it is turned on.