The Minister of State, Dr Stephen Ladyman, this week signed the 'LEDs are legal on bikes' order; and provided there are no parliamentary objections, it should become law in October.
The details were decided in close consultation with Chris Juden, technical officer of the CTC.
“This is a welcome liberalisation of cycle lighting law because provided they are bright enough, flashers front and rear will not only be legal, but will be all the lights you need," said Juden.
To be legally approved a light may flash at least once and not more than four times per second with a brilliance of at least four candle-power. Most of the better quality flashing lights on sale today, meet that simple requirement.
"Unfortunately [the Department for Transport] felt unable to make any changes beyond the matter of flashing lights," aid Juden.
"This will have some strange and unintended consequences. Since lamps emitting a steady light must still conform with BS6102/3 and all that entails, it now becomes much simpler to be legal by flashing than not! DfT are aware of this paradox and intend to add a recommendation to the Highway Code (currently also under review) to use a steady headlamp on unlit roads."
CTC continues to campaign for a similar, simple legal approval of lamps emitting steady light, and for a permitted alternative to pedal reflectors in cases where these cannot be used or seen.
"Until then, cyclists who light their way with one of those brilliant rechargeable headlamps, that emit thousands of candle-power but are non-the-less, non-British Standard, can most easily make themselves legal by also fitting a little 4-candela flasher," said Juden.