# The Road Vehicles Lighting Regulations 1989, Schedule 8: requirements relating to obligatory and optional hazard warning signal devices

Extent: E+W+S

Every hazard warning signal device shall–
(a) be operated by one switch;
(b) cause all the direction indicators with which a vehicle or a combination of vehicles is equipped to flash in phase;
(c) be provided with a circuit-closed tell-tale in the form of a flashing light which may operate in conjunction with any direction indicator tell-tale; and
(d) be able to function even if the device which controls the starting and stopping of the engine is in a position which makes it impossible to start the engine.

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Source: https://www.legislation.gov.uk/uksi/1989/1796/schedule/8 (the official version)
Page: https://openlegislation.uk/road-vehicles-lighting-regulations-1989/schedule-8
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.