Has the status of a basic safety publication in accordance with the principles given in IEC Guide 104 and ISO/ IEC Guide 51. Provides general rules for the use of certain colours or numerals to identify conductors with the aim of avoiding ambiguity and ensuring safe operation. These conductors ma be applied in cables or cores, busbars, electrical equipment and installations. This edition has significant technical changes with respect to the previous edition. This includes addition of subclauses 5.3.4 to 5.3.6 - Use of bi-colour combinations, addition of subclause 6.2 - Identification of certain designated conductors, and addition of a new Annex A (informative) ' Identification of certain designated conductors by means of colour code and alphanumeric' .