This International Standard is applicable to industrial microwave heating equipment and installations used for the purpose of thermal application to loads containing water or moisture.These applications comprise heating and drying of partially conductive or non-conductive materials@ such as wood@ textiles@ paper@ foodstuffs@ etc.@ in both normal and protective atmospheres@ using for example@ inert gas@ vacuum or heating materials@ which respond to microwaves showing heating effects. For other loads (for example@ plastics)@ the test methods are under consideration.This standard relates to microwave heating installations in the frequency range from 300 MHz to 300 GHz.This standard relates to microwave heating equipment normally operating under continuous rated conditions.Equipment operating at the lower range of the microwave frequency spectrum@ i.e. between 300 MHz and 600 MHz@ may use vacuum tubes or alternative microwave emitters. If the power output measurement systems specified in this standard cannot be applied for particular applications within this frequency range@ then the applicable systems would be those of IEC 61308.The main purpose of this standard is to specify test methods for industrial microwave heating installations. Due to the large variety of microwave heating applications@ any output power obtained as a result of these tests should not be taken as representing the amount of power dissipated in a particular product in a load microwave heating installation@ but@ in certain instances@ the output power can be used as an indication of performance.