A. The director is authorized to adopt standards and specifications applicable to lighting equipment on and special warning devices to be carried by school buses consistent with the provisions of the Motor Vehicle Code [66-1-1 N.M. Stat. Ann.] and supplemental thereto, except that the standards and specifications may designate and permit the use of flashing warning signal lights on school buses for the purpose of indicating when children are boarding or alighting from any school bus. Such standards and specifications shall correlate with and, so far as possible, conform to specifications approved by the society of automotive engineers.

B. It is unlawful to operate any flashing warning signal light on any school bus except when the school bus is stopped or is about to stop on a roadway for the purpose of permitting school children to board or alight from the school bus.