This standard is a basis for the establishment of performance@ limited electrical and mechanical interchangeability@ and safety requirements of equipment described. It is also a basis for assistance in the proper selection of such equipment. This standard describes electrical@ mechanical@ and safety requirements of liquid-immersed distribution and power transformers@ and autotransformers and regulating transformers@ single-phase and polyphase@ with voltages of 601 V or higher in the highest voltage winding. This standard applies to all liquid-immersed distribution@ power@ and regulating transformers that do not belong to the following types of apparatus: a) Instrument transformers b) Step voltage and induction voltage regulators c) Arc furnace transformers d) Rectifier transformers e) Specialty transformers f) Grounding transformers g) Mobile transformers h) Mine transformers