Regulation 14 Warning lamp
A warning lamp shall consist of a device which—
(a)
shows an intermittent amber light having a flashing rate of not less than 55 nor more than 150 flashes per minute; and
(b)
is illuminated by either—
(i)
a single source of light; or
(ii)
two or more sources of light mounted adjacent to each other and flashing in such a manner that all the sources of light are illuminated and extinguished simultaneously.