43. In a drift where vehicles circulate on rails, one of the following standards shall be respected:(1) clearance of one of the following minimum widths shall be provided for pedestrians between the wall of the drift and the farthest point of the vehicles travelling therein:(a) when clearance is provided on both sides of the drift, 450 mm (17.7 in);
(b) when clearance is provided on only one side of the drift, 600 mm (23.6 in);
(2) safety bays shall be installed in the walls of the drift at intervals not exceeding 30 m (98.4 ft); they must be clear at all times, at least 1.5 m (4.9 ft) in width, 1.5 m (4.9 ft) in depth and 2 m (6.6 ft) in height, at a right angle to the wall of the drift and clearly identified by a notice inscribed on both sides with the words “BAIE DE SÉCURITÉ” in letters 102 mm (4 in) high. The notice shall hang from the roof of the drift in front of the safety bay.