National Air Duct Cleaners Association – Cleanliness Verification Testing
Whether installing new duct work or verifying your original HVAC duct system has been cleaned properly, CDA offers two options for Duct Cleanliness Verification.
Surface Comparison Test (Non-analytical method):
This method is used to determine the cleanliness of both the non-porous and porous HVAC system component surfaces. The surface conditions are evaluated by comparing the visible characteristics of the tested surface before and after cleaning procedures have been implemented. CDA provides photographic documentation and a cleanliness verification letter indicating either a pass or fail.
NADCA Vacuum Test (Analytical Method):
This method is used for scientifically evaluating particulate levels on non-porous HVAC system component surfaces. Using this procedure, a NADCA Vacuum Test Template is applied to the interior portion of the HVAC system duct work while a vacuum cassette with filter media is attached to a pre-calibrated air sampling pump. The open face of the filter cassette is passed over the two 2 cm x 25 openings within the template twice for a total tested surface area of 100 square cm. The cassettes are then re-sealed and sent to a third-party laboratory for analysis. CDA provides photographic documentation and cleanliness verification letter indicating either a pass or fail.