Determination of Locations of High Concentration of Indoor Air Pollutants Using Air Flow Measurements and Modelling

Abstract

Sick Building Syndrome (SBS) is a malady experienced by occupants after prolonged exposure to various indoor air pollutants that are resident in enclosed spaces. Often, these indoor air pollutants are hardly detectable by normal human senses, and occupants are unaware of their exposure. In places of work, people suffering from SBS tend to become less productive. There is an economic impact brought about by this malady. One form of intervention is to install indoor air pollution monitors in enclosed areas with a significant number of occupants who spend considerable time in these facilities. These monitors are usually installed in locations that are suspected to have high concentrations of indoor air pollutants, and the number of units installed may vary according to considerations such as room size, the number of suspected areas of high pollutant concentrations, and layouts of room fixtures and furnishings. Since sophisticated monitoring systems may be expensive, there are limitations in the number of units that can be deployed. Identification of areas with high pollutant concentration in an enclosed facility allows for an optimal number of monitors to be deployed. Airflow and CO₂ measurements were taken in two different indoor sites. The results of the measurement will be used as input in future simulations that will be employed to optimize the distribution of sensors. The center of a room is determined to be a zero-velocity region which poses a challenge in future simulations, while additional measurement runs with greater than 3 occupants are recommended since the resulting CO₂ concentration of 478 ppm is more similar to the ambient concentration, which indicates the negligible contribution of the CO₂ sources, and a challenge in simulation.