Characteristics of Indoor Inhalable Particle Size Distribution in Under-floor Air Distribution System without Filters / 环境与健康杂志

ABSTRACT

Objective To know the characteristics of size distribution of the inhalable particles in the indoor air in the condition the under-floor air distribution systems were used and to study the effect of human activities and smoking. Methods The frequency of inhalable particulate matter was determined in Jun.-Jul.,2007. The surface area and mass concentration were calculated based on the assumption that the particulate was sphere and its density was 1g/cm3. The relationship between frequency, surface area, mass concentration and particle size were shown in logarithmic plot. Results It was found that the logarithm of cumulative frequency and the logarithm of diameter was a linear relation, the logarithm of cumulative total surface area and diameter was a linear relation and the logarithm of cumulative total mass and diameter was a linear relation. Particle of no less than 1 micron increased due to human activities, total mass concentration were two times the concentration of no human activities. The particle of no larger than 1 micron may increase due to smoking. Conclusion The diameter of the particle matter has relationship with the cumulative frequency, the cumulative total surface and the cumulative total mass.