Page "IEC 60446" Paragraph 11

British Standard BS 7671: 2001 Amendment No 2: 2004 adopted the IEC 60446 colours for fixed wiring in the United Kingdom, with the extension that < font color ="# 808080 "> grey </ font > can also be used for line conductors, such that three colours are available for three-phase installations.

This extension is expected to be adopted across Europe and may even find its way into in a future revision of IEC 60446.