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Safety Measures in Trial Pits and Trenches for Underground Cabling Works

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 excavation. Local councils may have more onerous conditions that need to be met.
  • Collapse or flooding of trenches.
  • Lack of ventilation or suitable lighting.
  • Dangerous gases.
  • Confined working space.
  • High temperatures.
  • Traffic hazards

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