The best way to prevent a building’s indoor pollutant(s) is to eliminate or control pollutants at the source. Indoor pollutants are substances or particles that can adversely affect the indoor air quality (IAQ) of a building and the health, comfort, and productivity of the occupants. Indoor pollutants can originate from various sources, such as building materials, furnishings, cleaning products, combustion appliances, outdoor air, or occupant activities. Eliminating or controlling pollutants at the source can prevent them from entering or spreading in the indoor environment, which can reduce the exposure and risk for the occupants. Some examples of source control strategies are: using low-emitting materials, installing local exhaust ventilation, sealingcombustion appliances, implementing green cleaning practices, and prohibiting smoking13. References: LEED v4 Green Associate Candidate Handbook1, EPA’s Indoor Air Quality3