Indoor Aerosols – Calculation of Zonal Particle Concentration and Particle Deposition in the Human Respiratory Tract

Abstract

This study presents a modeling approach to calculate the particle concentration in mechanically conditioned indoor environments and predict particle deposition in the Human Respiratory Tract (HRT) by combining two aerosol models. The developed Indoor Aerosol Model (IAM) combines the semi-empirical Respiratory Deposition Model (RDM) presented by the International Commission on Radiological Protection (ICRP) in its publication 66/130 with a Material Balance Model (MBM). This enables the determination of total regional deposition fractions in the HRT for different particle diameters, subjects, levels of exertion or respiration types. These total regional deposition fractions are then incorporated into the MBM, which can be used to determine the number and mass of particles deposited in the HRT over a maximum period of 24 hours. Furthermore, the time history of the airborne particle concentration, as well as the surface loading and, in addition, the particle fate can be determined for well-mixed single zones.