This SAE Recommended Practice sets forth the instrumentation and procedure to be used in measuring exterior sound levels for powered mobile construction equipment of 20 rated bhp and over. It is not intended to cover operation of safety devices (such as backup alarms) and equipment designed primarily for operation on highways or within factories and building areas, aircraft, or recreational vehicles, such as snowmobiles and boats. The sound levels obtained by using the test procedures set forth in this SAE Recommended Practice are repeatable and representative of the sound levels generated by the equipment during normal operating conditions.