It has been announced today that in a joint venture between the IET, BASEC and CENELEC that harmonised coloured cable cores are to be discontinued.
Prior to 2004 the standard colours for low voltage electricity fixed wiring in the UK were red, yellow and blue for phases, and black for neutral. This was replaced with brown, black and grey respectively for phases, and blue for neutral to harmonise the UK with the rest of the EU.
However, investigations by the BSI/BEC national safety committee have prompted a return to the previous industry standard colours of pre 2004 installations.
It has been found that the harmonised colours which are far less easily distinguishable in low light, have been responsible for upto a 34% year on year increase of indemnity insurance claims from professionals working within the electrical industries.
An independent study funded by the BSI found evidence of several incidents directly associated with wrongly connected harmonised wiring, ranging from small cases of damage to electronic equipment, to very serious incidents including overcurrent protective devices being rendered inoperable.
RoSPA have reported that the number of DIY related accidents relating to electrical work has also risen dramatically since 2004.
Non-harmonised cable is expected to be back on sale in early June and it is hoped that 85% of the cable on sale will be pre-harmonisation colours by the end of the year.
It is acceptable to continue using harmonised cable until stocks are exhausted.
References to harmonised wiring colours in BS7671 will be changed in amendment 1 of BS7671:2008
