Safe system of work: Unstable ground or surfaces

If accessing unstable ground or surfaces, including mud flats, rescue paths for access and egress need to be carefully planned and established. A safe system of work that is capable of recovering emergency responders, and casualties if present, should be put in place. An example of this is a recoverable system using rope equipment, but that may not be appropriate in all circumstances.

Personnel should avoid walking on unstable ground or surfaces. If this is not possible, specialist equipment should be used to mitigate the risk of collapse. The use of inflatable rescue paths and other types of platform may spread the weight and provide a stable platform to work from. Inflatable rescue paths and sleds are buoyant and may reduce the risk of immersion when working on an unstable surface, such as ice on a body of water.

When working on unstable ground or surfaces, there should be a safe system of work in place, which is capable of recovering casualties and emergency responders. For more information refer to Search, rescue and casualty care – Rescue of a casualty from unstable ground.

Buoyancy aids should be used if there is a risk of submersion in water. However, the rescue of people wearing automatically inflated buoyancy aids via a hole in the ice will be difficult and hazardous.

When working on or near mud in tidal areas, the use of suitable rescue craft should be considered. Tide charts or timetables should form part of the decision making, especially if the area is subject to rapid submersion. For more information refer to Water rescue – Check water and tidal conditions.

When transporting equipment consider towing or using backpacks or bags to allow the use of hands whilst moving and reduce the risk of losing dropped equipment.

Working on unstable ground or surfaces

Personnel should be aware of the physical condition of the ground or surfaces they are working on. They may be steep, slippery or have loose surface materials and be more unstable than they appear to be.

When working on unstable ground or surfaces, the area should be monitored continually to spot any movement or dipping; this may indicate subsidence and possible collapse into unidentified voids. If the ground or surface is frozen, the area should be monitored continually for signs of thawing that could impact on stability.

If a flow of water could worsen ground conditions, consideration should be given to:

• Channelling water to sacrificial areas
• Containing, diverting or controlling the use of fire water to reduce the impact on ground conditions; for more information refer to Environmental protection – Fire water run-off.

Working on or moving vehicles on unstable ground or surfaces should be avoided and care should be taken whenever vehicles are driven off-road. An assessment should be made to ensure that the surface can take the weight of the vehicle, avoiding the possibility of it becoming stranded. For more information refer to Operations – Position fire and rescue service vehicles safely.

At some locations there may be on-site machinery or vehicles that are suitable for use on unstable ground or surfaces. For more information refer to:

• Industry – Use competent people to operate on-site machinery
• Industry – Use competent people to operate on-site vehicles

Careful siting of equipment or vehicles, including aerial appliances, will be required and ground conditions should be constantly monitored. The equipment or vehicles may have to be relocated if the ground or surface they are on becomes too unstable.