The ITU Radiocommunication Assembly considering a)that the current set of definitions of the spectral properties of transmitter emissions (necessary bandwidth, occupied bandwidth, out-of-band emission, spurious emission, etc.) contained in Article 1, Section VI, of the Radio Regulations (RR) essentially came into being through the work of the World Administrative Radio Conference (Geneva, 1979);b)that the successful determination of limits in respect of those properties and the ability to perform the corresponding monitoring by means of measurements depend to a large extent on the correctness and clarity of all those definitions, both individually and collectively.