How can personal occupancy levels affect indoor air quality (IAQ)?

Personal occupancy levels have a significant impact on indoor air quality (IAQ) primarily because the number of people present in a space can directly influence the accumulation of pollutants and the consumption of available resources such as oxygen.

When occupancy levels are higher, the concentrations of indoor pollutants tend to increase. This is due to various human activities that generate pollutants, such as breathing, skin shedding, and use of electronic devices, as well as the emissions from furnishings and other indoor materials that can be exacerbated by the presence of more occupants. For example, carbon dioxide levels can rise significantly in crowded settings, as more people exhale CO2. This can also come from activities like cooking, smoking, or using cleaning products, which can lead to an increase in volatile organic compounds (VOCs) and particulate matter.

In contrast, lower occupancy levels may allow for better pollutant dispersal and provide more opportunity for ventilation systems to effectively reduce pollutant concentrations. However, this does not impact the fundamental idea that increased occupancy typically leads to higher concentrations of pollutants. Therefore, understanding the correlation between occupancy levels and pollutant concentration is critical for managing and improving indoor air quality.