I completed a duct lining project today on exposed commercial HVAC ductwork. After performing air quality testing to establish baseline conditions, I prepared the interior surfaces through detailed cleaning and degreasing processes. The duct lining application required careful attention to seams and corners to ensure complete coverage. I installed multiple access points to facilitate proper material application and inspection. During the process, I maintained constant negative air pressure to ensure proper curing and prevent any airborne particles from entering the occupied space. After completion, I conducted air velocity measurements to verify the new surface didn't restrict airflow.