(a) Patrol members shall (1) encourage pupils to refrain from crossing streets and highways at other than regular crossings;
(2) direct pupils not to cross streets and highways when the presence of traffic renders crossing unsafe;
(3) when directed, assist pupils to safely board or leave school buses.
(b) A patrol member may not, under any circumstances, be permitted to direct vehicular traffic or be stationed in a street or highway while performing the duties of a patrol member.