ISO 20361:2015 specifies all the information necessary to carry out efficiently and under standardized conditions the determination, declaration, and verification of the airborne noise emission of liquid pumps or pump units. It specifies the noise measurement methods and the operating and mounting conditions that shall be used for the test.Noise emission characteristics include emission sound pressure levels at specified positions and the sound power level. The determination of these quantities is necessary fordeclaring the noise emission values, and purpose of noise control at source at the design stage. The determination of these quantities is also necessary for comparing the noise emitted by liquid pumps on the market.The use of ISO 20361:2015 ensures the reproducibility of the determination of the airborne noise-emission characteristics within specified limits determined by the grade of accuracy of the basic airborne noise measurement method used. Noise measurement methods according to ISO 20361:2015 are engineering methods (grade 2) and survey methods (grade 3).ISO 20361:2015 does not deal with the characterization of the structure-borne sound and liquid-borne noise generated by liquid pumps.