Factors influencing indoor PM2.5 concentration in rural houses of northern China

In traditional houses in rural areas of Northern China, most traditional heating systems, heated by mini-stove in the kitchen, usually take agricultural residues as fuels resources. Besides, burning cave under the ground-floor of a rural house is also widely used. The higher PM2.5 concentration is crisis for human health. In this study, PM2.5 concentration, temperature, relative humidity inside and outside the houses have been measured, moreover the factors impact on I/O rate coefficient has been discussed. The results show that the I/O rate coefficient in the evening is 2.5 times greater than the I/O rate coefficient in the daytime. I/O rate coefficient of PM2.5 concentration is positive related to air temperature difference between indoor and outdoor. In addition, the impact of outdoor wind speed and predominant wind direction on the PM2.5 emission has been studied.