| Synopsis: |
Trenches occur as part of activities in building works and utilities maintenance; pits occur in a variety of locations such as agricultural and industrial sites. Risks vary with the depth of the trench or pit and ground conditions surrounding the area. The entry of water, other fluids or gases creates additional hazards for operational personnel. Typical incidents involve workers being: trapped or buried beneath ground level; crushed by movement of soil, equipment or machinery; falling into an open pit or trench; drowning. Trench or pit collapse can result from excessive rainfall, vibration from nearby heavy plant, insufficient piling and bracing of the trench sides, heavy plant positioned too close to trench/pit. An incident may require the removal of a quantity of soil, or of machinery or plant to access trapped persons. Typical hazards and associated risks are outlined, along with key control measures to be taken by the Fire and Rescue Service. |