Applies to wires used for the internal wiring of transmission equipment, telephone and telegraph equipment, equipment for data processing, and electronic equipment. Covers wire construction and dimensions. Specifies mechanical, climatic and electrical requirements including requirements for thermal stability. Dimensions and electrical properties of solid conductors are indicated in two tables. Five appendices cover testing of the coating for pinholes, cut-through test, melting point test, preferred colours, and calculation of the maximum diameter of insulated conductors. Shall be used in conjunction with IEC 189-1 Part 1.