What must be done to verify proper air distribution in ventilation systems under 62.1-2022?

• A. No verification is required.
• B. Balancing must be performed and documented testing conducted.
• C. Verification is optional and depends on the designer.
• D. Only visual inspection is required.

Answer: (B)

Verifying proper air distribution means proving that the system actually delivers the outdoor air and distributes it to spaces as designed. In 62.1-2022, field verification requires both balancing and documented testing. Balancing adjusts dampers, terminals, and reset devices so the measured airflow in each zone matches the design values. After balancing, testing provides recorded measurements of airflow at supplies, returns, and outdoor air additions, showing that the delivered rates meet the design intent. A visual inspection alone cannot confirm airflow quantities or distribution patterns, and making verification optional would leave IAQ unproven. So the required approach is balancing with documented testing.