About lifejacket lights

Lifejacket lights may show a steady light or a flashing light.
It must be white, as far as is practicable be visible all round and have a duration of at least eight hours.

A water activated light which uses a silver chloride battery. It is an intrinsically safe unit. The light operates when the sealing plugs are removed and the unit is immersed in fresh or salt water.

The battery may be water activated—where the water either forms the electrolyte or

completes an electrical circuit, or it may be a lithium battery or normal dry cell. Activation of the light may be by manual operation or automatically on immersion. Flashing lights must be provided with a manual switch.