Q & A of the Day – What hand-held lights in car workshops?

Question: Mechanics in car repair workshops need light to work on vehicles. Sometimes they have to work in awkward places within or under the car itself. Where fixed lighting cannot provide necessary lighting levels in these areas, portable hand held light fittings are probably the only option.

Is there a regulation which states the maximum voltage of this type of hand-held luminaire (and lead with plug & socket outlet arrangement) used under these conditions?

It appears that the HSE suggests that 110V is used - though the Third edition of Electrical installation design by Bill Lovegrove (Blackwell ISBN 1-4051-0634-4- page 95) suggests that, though these leads should be discouraged, the voltage should be no greater than 50V (but does not reference this to any other document).

I cannot seem to find anything in BS 7671. Can you help?

Answer: The protective measure of automatic disconnection of supply in a Reduced Low Voltage (RLV) system may be used where, for functional reasons, the use of extra-low voltage is impracticable and there is no requirement for the use of SELV or PELV. The general requirements for RLV systems are given in Regulation Group 411.8 of BS 7671.

Although no special location of car repair workshops exist within BS 7671, RLV is the preferred option for portable hand lamps and hand tools up to 2kW, when used in a construction or demolition site. If you wish to use this method, it is allowable under BS 7671.

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