9. When the train either occupies a track circuit or operates a treadle the audible warning devices and the traffic light signals shall begin to operate and the barriers shall be lowered in accordance with the following sequence—
(a)the amber lights shall show and the audible warning shall begin. The lights shall show for approximately 3 seconds;
(b)immediately the amber lights are extinguished the intermittent red lights shall begin to show;
(c)4 to 6 seconds later, the barriers shall begin to descend and shall take a further 6 to 10 seconds to reach the lowered position;
(d)not less than 36 seconds shall elapse between the time when the amber lights first show and the time when the train reaches the crossing;
(e)both barriers shall begin to rise simultaneously as soon as possible after the train has passed the crossing and shall take 4 to 6 seconds to reach the raised position. The intermittent red road signals shall continue to show and the audible warning device shall continue to sound until the barriers have risen to an angle of at least 45 degrees above the horizontal.