Advanced airflow distribution methods for reducing exposure of indoor pollution

The adverse effect of various indoor pollutants on occupants’ health have been recognized. In public spaces flu viruses may spread from person to person by airflow generated by various traditional ventilation methods, like natural ventilation and mixing ventilation (MV Personalized ventilation (PV) supplies clean air close to the occupant and directly into the breathing zone. Studies show that it improves the inhaled air quality and reduces the risk of airborne cross-infection in comparison with total volume (TV) ventilation. However, it is still challenging for PV and other advanced air distribution methods to reduce the exposure to gaseous and particulate pollutants under disturbed conditions and to ensure thermal comfort at the same time. The objective of this study is to analyse the performance of different advanced airflow distribution methods for protection of occupants from exposure to indoor pollutants.
The study shows that due to complex boundary conditions of the indoor environment, the conventional ventilation methods, like mixing ventilation, may not be able to protect occupants from exposure to various indoor airborne pollutants. The latest developed advanced airflow distribution methods, like protected zone ventilation, downward ventilation, bed and chair incorporated personalized ventilation and localized chilled beam may be used to reduce the personal exposure to various indoor airborne pollutants and ensure thermal comfort. Regarding the exposure to exhaled airflow, the exposure risk can be as high as 20 times by using MV than PV method.