(a)Suitable protective clothing shall be provided for the use of operatives.(i)When operating valves or cocks controlling fluids which by their nature, pressure or temperature would be highly dangerous if a blow-out occurred or when cleaning chocks in systems containing such fluids if pressure is likely to exist behind the chocks;(ii)when there is danger of injury by absorption through the skin during the performance of normal duties or in the event of emergency;(iii)whenever there is risk of injury in handling corrosive substances , hot or cold articles and sharp or rough objects, and(iv)when there is the risk of poisonous materials being carried away on their cloths.