Paragraph 17 Beacons displayed with upright signs relating to the operation of light signalsI1
England, Wales and Scotland
For conveying the additional warning that drivers should take special care, a beacon which shows an intermittent amber light placed may be placed in combination with an upright sign provided for at item 61, 62 or 63 of the Part 2 sign table (upright signs giving information about the operation of traffic light signals).
The operating requirements for a beacon mentioned in sub-paragraph (1) are—
the peak intensity of light emitted by the lens or lenses of each such beacon must be—
if the period between individual flashes does not exceed ¼ of a second, not less than 100 candela on the principal axis of the relevant lens;
if the period between individual flashes exceeds ¼ of a second, not less than 2000 candela on the principal axis; or
if the period between the cessation of a double flash and the start of the succeeding double flash exceeds ¼ of a second, not less than 1000 candela on the principal axis;
each lens must be of such a shape and size that the perimeter of its area projected horizontally onto a vertical plane is capable of lying wholly inside a square having sides of 200 mm in length and wholly outside a square having sides of 100 mm in length;
the height of the centre of the lenses from the surface of the carriageway in the immediate vicinity must be not less than 800 nor more than 1500 mm; and
the rate of flashing must be not less than 55 nor more than 150 individual or double flashes per minute.
Annotations
Commencement
- I1
Sch. 14 Pt. 1 para. 17 in force at 22.4.2016, see reg. 1(b)