Regulation 12

Subject to paragraph (2), every motor vehicle shall be equipped —

Paragraph (1) shall not apply to a motor vehicle, if the vehicle is equipped with one efficient braking system with one mean of operation and that system is a split braking system.

Except as provided in paragraph (2), the braking system or braking systems of every motor vehicle shall be so designed and constructed that, notwithstanding the failure of any part (other than a fixed member or a brake shoe anchor pin) through or by means of which the force necessary to apply the brakes is transmitted, there shall still be available for application by the driver to not less than half the number of the wheels of the vehicle brakes sufficient under the most adverse conditions to bring the vehicle to rest within a reasonable distance.

In the event of such failure as referred to in paragraph (3), it shall not be necessary for brakes to be available for application by the driver to more than one wheel if the vehicle has less than 4 wheels and its unladen weight does not exceed one metric ton.

Nothing in paragraph (1) shall apply to a road roller, land implement, land tractor, light locomotive or heavy locomotive if the vehicle is equipped with one braking system with one means of operation.

Where a motor vehicle has, including every steering wheel, more than 3 wheels, at least one means of operation of its brakes shall be capable of causing brakes to be applied to all the wheels of the vehicle.

Where a vehicle has more than 2 steering wheels, only half the number of steering wheels shall be deemed to be the wheels of the vehicle for the purpose of paragraph (6).

Nothing in paragraph (6) shall apply to a light locomotive or heavy locomotive or to a motor tractor not forming part of an articulated vehicle.

The application of one means of operation of the brakes of a motor vehicle shall not affect or operate the pedal or hand lever of the other means of operation.

No braking system of a motor vehicle shall be rendered ineffective by the non-rotation of the engine.

All the brakes of a motor vehicle which are operated by one of the means of operation required by this rule shall be capable of being applied by direct mechanical action without the intervention of any hydraulic, electric or pneumatic device.

One at least of the means of operation required by this rule shall be capable of causing brakes to be applied directly and not through the transmission gear to not less than half the number of wheels of the vehicle.

Where a motor vehicle has more than 4 wheels and the drive is transmitted to all wheels other than the steering wheels without the interposition of a differential driving gear or similar mechanism between the axles carrying the driving wheels, it shall be deemed to be a sufficient compliance with paragraph (12) if —

For the purposes of this rule, every moving shaft to which any part of a braking system or any means of operation thereof is connected or by which it is supported shall be deemed to be part of that system.

No account shall be taken in the case of a vehicle registered after 1st June 1975 of any braking system whose means of operation is such that it applies the brakes progressively as a result of successive application of that device by the driver unless that means, at the first application, operates any hydraulic, electric or pneumatic device which causes brakes sufficient to bring the vehicle to rest within a reasonable distance.

Every motor vehicle which is equipped with a braking system which embodies a vacuum or pressure reservoir or reservoirs shall be provided with a warning device so placed as to be readily visible to the driver of the vehicle when in the driving seat in order to indicate any impending failure or deficiency in the vacuum or pressure system.

In the case of a vehicle the unladen weight of which does not exceed 3 metric tons and which is propelled by an internal combustion engine and equipped with a braking system embodying a vacuum reservoir or reservoirs, the vacuum therein being derived directly from the induction system of the engine, it shall not be necessary to provide a warning device referred to in paragraph (16) if, in the event of a failure or deficiency in the vacuum system, the brakes of that braking system are sufficient under any condition to bring the vehicle to rest within a reasonable distance.

Every goods vehicle registered on or after 1st July 1980 shall be equipped with a split braking system.