This Part of IEC 60076 defines sound pressure and sound intensity measurement methods from which sound power levels of transformers, reactors and their associated cooling devices are determined. NOTE For the purposes of this standard, the term "transformer" frequently means "transformer or reactor". The methods are applicable to transformers, reactors and their cooling devices either fitted to or separate from the transformer as covered by the IEC 60076 and IEC 61378 series. This standard is primarily intended to apply to measurements made at the factory. Conditions on-site can be very different because of the proximity of objects, including other transformers. Nevertheless, this standard is applied to the extent possible for on-site measurements.