This part of EN 1151 specifies a test code for the vibro-acoustic characterisation of circulation pumps as defined in EN 1151-1, and is limited to circulation pumps with threaded connections of 1½ inch. The test code comprises the test rig, the measurement method and the test conditions. The characterisation principle is based on measuring the structure-borne and the fluid-borne power transmitted respectively by vibration and pressure fluctuations in the pipe connected to a circulation pump.