This International Standard is applicable to industrial radio- or high frequency induction heating installations used for the purpose of thermal applications (e.g. for surface hardening, welding, soldering, melting, forging, zone refining of semiconductors, ect.). This standard relates to high frequency induction heating installations in the frequency range up to 300 MHz for power levels of 500 W and above, comprising high-frequency generators and inductors together with necessary mechanical devices for charge handling (e.g. hardening machines). The main purpose of this standard is to provide the test methods for the determination of output power of industrial high-frequency induction heating power sources.