Progress on Exposure Assessment of Indoor PM_2.5

This paper described the main sources and distribution properties of indoor PM_2.5, and reviewed the progress on the research of indoor PM_2.5 from four aspects, including the detection of concentration, time-behavioral activity patterns, estimation of exposure and potential dosage. Based on comparing the development of situation domestic and abroad, research issues for future studies on indoor PM_2.5 exposure in China were recommended.