This SAE Recommended Practice sets forth the instrumentation and procedures to be used in measuring sound levels at the operator station for powered mobile construction machinery of 15 kW (20 bhp) rated and over. This Recommended Practice is to cover machinery that has operator stations where the operator can either stand or sit and will be transported by the machine during its operation. The sound levels obtained by using the test procedures set forth in this SAE Recommended Practice are in general repeatable and are representative of the higher range of the sound levels generated by the machinery under field operating conditions, but do not necessarily represent the equivalent sound level over a field use cycle.