Deals with all aspects of safety (such as electrical, thermal and mechanical) of: a) Stationary or portable, single-phase or polyphase, air-cooled (natural or forced) isolating and safety isolating transformers; b) Stationary or portable, single-phase or polyphase, air-cooled (natural or forced) separating transformers, auto-transformers, variable transformers and small reactors. Has the status of a group safety publication in accordance with IEC Guide 104. This part 1 replaces Chapter I of IEC 60742 and IEC 60989.