When carrying out the work of cable laying in the underground transmission line, the trench is to be dug/ prepared. Trench work should be done by following safety precautions. All pits and trench work shall comply with WorkSafe requirements, particularly the WorkSafe Code of Practice: Excavation. They may include but are not limited to: When a pit is to be left open overnight, proper barrier mesh and flashing lights, etc as required or the pit must be covered. Soil must be piled safely back from the edge of the pit. Pits or trenches deeper than 1500mm in normal soil may require a ladder for access and require shoring, benching or sloping of the sides of them. Pits or trenches may require shoring if less than 1500mm deep and the soil is unstable. Undermining walls, foundations, streets or pavements are to be avoided otherwise appropriate shoring is required. All shoring, benching and sloping must be installed. Barriers shall be erected to vehicles inadvertently falling into the excavati...