In IAQP, what is meant by source control?

• A. Measures to reduce or eliminate contaminant generation at the source before it enters the indoor air.
• B. Increasing outdoor air regardless of contaminants.
• C. Filtering all incoming outdoor air only.
• D. Using only gas-phase filtration.

Answer: (A)

Source control means preventing contaminants from entering indoor air by eliminating or reducing emissions at their source. In IAQP, the idea is to design and operate spaces and processes so that pollutants are minimized before they ever become airborne, rather than relying solely on diluting or filtering them once they’re in the indoor environment. Examples include selecting low-emitting materials and products, enclosing or local-exhausting processes that generate dust, fumes, or vapors, substituting safer chemicals, proper storage, and ongoing maintenance to prevent leaks or spills. Because the generation of pollutants is reduced at the source, the overall air quality improves and less ventilation or filtration may be needed to achieve acceptable IAQ. This approach is favored in IAQP because it directly lowers occupant exposure by stopping contaminants at the origin, rather than addressing them after they’ve entered the building.