The Non-Return Damper (NRD) is an essential HVAC component designed to prevent reverse airflow in ventilation systems. By allowing air to pass freely in one direction and automatically blocking reverse flow, NRDs protect ductwork, filters, and critical equipment from contamination, pressure imbalances, and backflow damage.

Constructed from galvanized or stainless steel (SS 304/316), these dampers feature spring-loaded or gravity-operated blades that close tightly when airflow reverses. Their low-pressure drop design ensures minimal impact on system efficiency, while the powder-coated finish provides corrosion resistance for long-term use.

Non-Return Dampers are widely installed in cleanrooms, pharmaceutical plants, hospitals, laboratories, and industrial facilities where controlled ventilation and contamination prevention are critical. Available in circular, rectangular, and square duct configurations, NRDs offer easy installation and reliable performance for diverse HVAC applications.