The employer shall ensure at a construction site of a building or other construction work that -
(a) surroundings of a shaft used in excavation or tunnel work are protected from being washed away by construction of sufficient height ;
(b) where a building worker is required to enter a shaft at an excavation or tunnelling work, safe means of access is provided for such entry ;
(c) every shaft at excavation or tunnelling work is provided with a steel casing, concrete piping, timber shoring or other materials of adequate strength for the safety of building workers working in such shaft ;
(d) such casing and bracing are provided to a shaft at an excavation or tunnelling work up to the depth of such shaft at an excavation or tunnelling work according to the appropriate design for such casing and bracing ;
(e) a reinforced concrete raft and beam is provided around the opening of a shaft at an excavation or tunnelling work if the ground surrounding such opening is unstable or unsafe.