whenever the white downward arrow is illuminated above that same lane, the red cross is not also then illuminated.
(5) The significance of the light signals prescribed by this regulation shall be—
(a) the red cross conveys to vehicular traffic proceeding in the traffic lane above and in relation to which it is displayed the prohibition that such traffic shall not proceed beneath or beyond the red cross in the said traffic lane in the direction opposite to that in which the red cross faces until that prohibition is cancelled by a display over that traffic lane of the white downward arrow or by the display over that name lane or beside the carriageway of the traffic sign shown in diagram 6001 or of a traffic sign bearing the legend "End of lane control"; and
(b) the white downward arrow conveys to such traffic proceeding in the traffic lane above and in relation to which it is displayed the information that that traffic may proceed or continue so to do in the said lane beneath or beyond the said arrow and in the direction opposite to that in which that arrow faces.
37.—(1) Except where the Secretary of state authorises the use of traffic sign of another description, every traffic sign which is exhibited by a school crossing panel for the purpose of stopping any vehicle or vehicles in accordance with section 25 or the Act shall be of the size, colour and type shown in diagram 605.1.
(2) (a) A traffic sign for conveying the warning specified in the next following sub-paragraph to vehicular traffic which is approaching a place in a road where children on their way to or from school or on their way from one part of a school to another cross or seek to cross that road may be erected on or near a part of that road in advance, in relation in on-coming traffic, of the said place;
(b) the warning conveyed by the traffic sign mentioned in the preceding sub-paragraph shall be that such a place as aforesaid lies ahead and is either being patrolled by a school crossing patrol or is otherwise in use by children under the supervision of a teacher or other school officer, a traffic warden or a constable in uniform;
(c) the said sign shall be of the following size, colour and type, that is to say—
(c) 2 lamps mounted vertically one above the other facing in the same direction and each showing an intermittent amber light shall be used;
(c) each lamp shall be separately illuminated and the effective diameter of the lens thereof shall be not less than 135 nor more than 155 millimetres;
(c) each lamp shall be so fitted that the aware of the light source which illuminates its lens is located on the axis of that lens; and
(c) each lamp shall show an intermittent amber light at a tale of flashing of not less than 60 nor more than 90 flashes per minute and in such a manner that the light of one lamp is always shown at a time when the light of the other lamp is not shown.
