IEC 60519-6:2011 is applicable to equipment using microwave energy alone or in combination with other kinds of energy for industrial heating of materials. This part is applicable to industrial microwave heating equipment operating in the frequency range 300 MHz to 300 GHz. This third edition cancels and replaces the second edition published in 2002 and constitutes a technical revision. The significant changes with respect to the previous edition are as follows: - the third edition of IEC 60519-1:2003 has been taken into account (the structure of clauses was adapted to it as far as practicable); - some definitions are modified or brought into line with IEC 60050-841:2004; - clauses on abnormal operation, access openings, microwave enclosure and barriers are added; - the microwave leakage measurements are in a normative Annex A; - an informative Annex B on the rationales for microwave exposure and leakage limits is added; - Bibliography is added.