Level Crossing (Trooperslane) Order (Northern Ireland) 2004

11.  When the ‘lower’ push-button is pressed or the train occupies a track circuit, the sequence of events to close the crossing to road traffic shall begin. The sequence shall be –

(a) the amber lights shall immediately 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 show;

(c) 4 to 6 seconds later the left-hand side barriers shall begin to descend and shall take a further 6 to 10 seconds to reach the lowered position;

(d) the right-hand side barriers shall then begin to descend taking 6 to 10 seconds to reach the lowered position;

(e) the audible warning shall stop when all the barriers are fully lowered.