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by the NFCC

Control measure

Cordon controls: Unstable or collapsed natural or built environments

Control measure knowledge

To prevent collapse or further collapse of an unstable surface, trench, excavation or other natural or built environment, access to the surrounding area 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 instead moved a safe distance away to prevent slippage or collapse.

Where possible, vehicles, machinery or equipment creating vibration should be isolated. Incident commanders need to assess the risk of moving vehicles, machinery or equipment to a safe distance as the movement and redistribution of weight could lead to further collapse.

Strategic actions

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

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

Tactical actions

Incident commanders should:
  • Establish cordon controls for an unstable or collapsed natural or built environment at an appropriate distance from the hazard area

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

  • Consider isolating, controlling or moving vehicles, machinery or equipment for incidents involving an unstable or collapsed natural or built environment