CONTRIBUTION OF DIFFERENT VENTILATION STRATEGY TO NON-UNIFORM EXPOSURE OF COUGH DROPLETS

Abstract

The purpose of this study is to evaluate the contribution of the each ventilation strategy to the exposure of cough droplets and other factors that may contribute in getting the occupant exposed to cough droplets within the space of an office. The method of study adopted was to conduct a risk assessment of various location of the room and identify the factors which may contribute to the spread of cough droplets through the study of exposure level. Artificial coughs were used to simulate respiratory fluid containing glycerin and distilled water and they simulated a cough puffs released by an infected person. An aerosol counter was used to collect the data from the inhalation zone of a manikin and analyzed. Using the numerical data, a prediction or assumption was given with the consideration of the position, airflow rate and the nature of each ventilation system. From the results, the ventilation flow and coughing orientation were found to play significant roles in aerosol transport, leading to different exposure levels at different positions. Others such as size of the particles, distances and position of the diffuser also play a part in distributing the cough droplets to the inhalation zone.