- The length of time the vehicle has been in the water
- The depth and speed of flow of the water
- If the vehicle is thought to be occupied or unoccupied
When approaching a road vehicle in water, the scene survey should include looking for signs of occupancy in the road vehicle, such as personal possessions or fastened seatbelts.
A dynamic risk assessment should consider the window of opportunity for carrying out immediate life-saving actions, using safe working practices and competent personnel to carry out tasks. This may mean considering the speed of water flow and how quickly an area is becoming inundated, the depth of the water and the likely path of travel the vehicle may take if it moves.
Personnel should avoid entering a submerged or partially submerged vehicle as this may affect its stability, potentially resulting in entrapment. The surface of a road vehicle is likely to be extremely slippery and standing on top of it is not recommended.
Leaning into a vehicle to assist a casualty while wearing automatically inflating life jackets should be avoided. If the device is activated while fully or partially in a vehicle, either by accidentally triggering the device or if sensors become submerged, the inflated life jacket may cause the wearer to become trapped.
Casualties can be encouraged to self-extricate once appropriate control measures are established. For more information refer to Rescue from a road vehicle in water.
Electric or hybrid road vehicles
Electric and hybrid road vehicles should be isolated in the same way as conventional road vehicles, using the vehicle ignition. This will assist in preventing the unwanted movement of the vehicle. High-voltage circuitry should not be disconnected or touched if a vehicle is submerged, to prevent the risk of electrocution and the transmission of electricity through the water.
An appropriate scene survey may be necessary to determine if the high-voltage system has been compromised through damage as a result of an accident. If high-voltage batteries have been damaged, there may be a risk of electric shock and transmission of an electric current through the body of water.