This SAE Standard is applicable to machinery of 15 kw (20 bhp) rated and over, that have operator stations where the operator can either stand or sit and will be transported by the machine during its operation. It is not intended for use with agricultural equipment. The sound levels obtained by using the test procedures set forth in this SAE Standard 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. For measurement and calculation of the operator's sound exposure, use SAE Recommended Practice J1166a.