scope:

NEN-EN 1751 specifies methods for the testing and rating of dampers and valves used in air distribution systems with pressure differences up to 2000 Pa. The tests incorporated in this European Standard are: a) leakage past a closed damper or valve (for classification see annex C); b) casing leakage (for classification see annex C); c) flow rate/pressure requirement characteristics; d) torque: (see annex A); e) thermal transmittance: (see annex B). The acoustic testing of dampers and valves is not included in this standard. The tests specified above apply to the following: a) measurement of leakage past a closed damper or valve; b) measurement of casing leakage; c) determination of flow rate and pressure requirements; d) measurement of torque characteristics (see annex A); e) measurement of thermal transfer characteristics to determine insulation properties (see annex B).