Developing parameters for multi-mode ambient air models including the nanometer mode

[摘要] The particle count, surface and mass in an occupied space can be modeled when the HVAC system airflows are known, along with the particle-size distribution for outdoor air, internal generation rates as a function of particle size, and the efficiency as a function of particle size for filters present. Outdoor air particle-size distribution is rarely available, but measures of particle mass concentration, PM2.5and PM10, are often available for building locations. Outdoor air aerosol size distributions are well modeled by sums of two or three log-normal distributions, with essentially all mass in two larger modes. Studies have also shown that some mode parameters are, in general, related by simple functions. This paper shows how these relationships can be combined with known characteristics of PM2.5and PM10samplers to create reasonable inclusive models of outdoor air aerosol-size distributions. This information plus knowledge of indoor particle generation allows calculation of aerosol mass in occupied spaces. Estimation of parameters of aerosol modes with sizes below100 nm and measurement of filter efficiencies in that range are described.

[发布机构] Department of Energy, Politecnico di Torino, Turin; 10129, Italy^1;Environmental Quality Sciences, Louisville; KY; 40204-2106, United States^2

[效力级别] 医药卫生

[关键词] Aerosol size distributions;Estimation of parameters;Filter efficiency;Indoor particles;Internal generation;Log-normal distribution;Particle counts;Particle mass