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Developed and maintained
by the NFCC

Control measure
Cordon controls: Unstable or collapsed excavations

Control measure knowledge

To prevent collapse or further collapse of an unstable surface, trench excavation or other natural or built environment, access to the area surrounding it should be carefully controlled.

Equipment entering the area should be limited to essential items only.

An area should be identified a suitable distance away from the hazard area for personnel, equipment, machinery and any items being removed including debris. Material removed from a trench should not be placed above the area where excavation is taking place but moved a safe distance away to prevent slippage or collapse.

Where possible vehicles, machines or equipment creating vibration should be isolated or moved to a safe distance. The movement of redistribution of weight should be risk assessed considering the risk of further collapse.

Strategic actions

Fire and rescue services should:
  • Ensure personnel have access to appropriate specialist advice and equipment to assess unstable natural or built environments

  • Consider providing local equipment or access to specialist resources to enable personnel to work safely in the area around unstable natural or built environments

Tactical actions

Incident commanders should:
  • Assess the structural stability of the working environment and establish cordon controls at an appropriate distance from the hazard area

  • Identify an appropriate area to store equipment, personnel and debris to prevent further collapse of an unstable natural or built environment

  • Risk assess the movement of any machinery, equipment, or vehicles prior to moving them or requesting they are moved

  • Request that machines, equipment and vehicles are kept isolated or moved to a safe distance away from a natural or built environment