Deals with safety of electroheat installations with electron guns and applies to all electroheat applications with electron guns. May also be used for non-thermal applications with electron guns and equipment employing glow discharge systems. Applies also to high-voltage sources feeding electron guns. The main changes with respect to the previous edition cover:- new editions of IEC publications taken into account;- addition of new clauses;- requirements for the earthing system updated;- arrangement of return conductor changed.