During construction and start-up, which actions help maintain IAQ?

• A. Use filters, protect materials from moisture, and test controls.
• B. Seal all ductwork and ignore moisture risk.
• C. Increase outdoor air to 100% during construction.
• D. Delay all testing until occupancy.

Answer: (A)

During construction and start-up, controlling contaminants and ensuring the ventilation system operates as designed is essential for maintaining IAQ. Using filters during this phase helps capture dust and particles generated by construction activities, reducing what finishes and occupied spaces are exposed to. Protecting materials from moisture prevents mold growth and moisture-related off-gassing that can degrade air quality and lead to costly remediation later. Testing controls—verifying that fans, dampers, sensors, and interlocks work as intended—ensures the ventilation rates, filtration performance, and system sequencing are correct, so the building will meet IAQ goals once occupied.

Why the other approaches aren’t as effective: sealing ductwork and ignoring moisture risk can trap contaminants and create mold problems, worsening IAQ. Increasing outdoor air to 100% during construction isn’t practical or necessary and can introduce outdoor pollutants and humidity, plus it wastes energy. Delaying all testing until occupancy means problems may go undetected during construction, allowing IAQ issues to persist once people are using the space.