scope:

This Standard establishes requirements for determining, in accordance with a standardized procedure, the noise, (parameter: sound power level) emitted into the surrounding air by heat pump units with electrically-driven compressors used for heating, heating and cooling and for heating sanitary water. Two methods for determining the sound power levels are specified in order to avoid unduly restricting existing facilities and experience. The first method is based on reverberant room measurement (see ISO 3741 and ISO 3742); the second is based on measurements in an essentially free field over a reflecting plane (see ISO 3744 and ISO 3745). Either method may be used in compliance with this European Standard.