Hazard Primary surface extrication of casualties following collapse of a structure
Following the partial or full collapse of a structure, initial attending fire and rescue service personnel may have to extricate casualties located on the surface of the debris pile or those entrapped because of fallen masonry and metalwork, before specialist resources such as Urban Search and Rescue (USAR) or canine search teams arrive.
The following details the framework for the CFOA National Resilience Six Stages of Rescue. Although initial attending fire and rescue service personnel should be aware of this information, their participation in this type of incident may need to be restricted to non-specialist activities.
To assist in the creation of an operational plan, Six Stages of Rescue provides a framework for the organisation of any collapsed structure incident. Whilst it is likely that there will not be a clear delineation between each stage, and there will be times when stages overlap, the incident command structure must ensure that each stage is undertaken and completed. This logical and progressive approach will mean that rescue personnel will maximise effectiveness, particularly in the early stages of an incident.
In simple terms, any operations conducted in a sector will have a defined search phase followed by a defined rescue phase, although these two phases may run concurrently across multiple sectors dependent on the size and scale of the incident.
Progression through the Six Stages of Rescue takes a considerable time even at a small, single dwelling collapse. The tactical plan should take account of this and the resources required to achieve a safe and successful conclusion to the incident.
Rescue operations are conducted under the following six stages:
R Reconnaissance and survey
E Elimination of utilities
P Primary surface search and rescue
E Exploration of voids and spaces
A Access by selected debris removal
T Termination by general debris removal
Stage 1: Reconnaissance and survey
The area is searched for possible casualties (surface and/or buried), and the evaluation of the structure's stability and potential danger to rescue personnel is performed. Immediately after a collapse, the debris of the building is very unstable and prone to additional movement. Rescuers must assess the nature of the scene and the pattern of the collapse before entering onto a pile of rubble to ensure their own safety and that of those potentially buried in it. Thermal imaging cameras may assist in this task. Before attempting rescues, shoring may be necessary to prevent movement.
Gather as much information as possible at the onset of the incident. Intelligence regarding the last known locations and activities of those believed to be in the structure will greatly assist in developing a plan for recovery efforts. Preliminary efforts should be concentrated on areas where people were last seen or known to be.
It is suggested that a search co-ordinator be designated to interview those who may have escaped the collapse, were eyewitnesses, or were in the building and rescued early in the effort. A list of the people normally in the building should be obtained if one is available.
Stage 2: Elimination of utilities
During this stage of the incident, all utilities must be evaluated and controlled for safety. If necessary, utility services should be isolated before any rescue work proceeds, and if this is not possible, the condition of the utilities present in the structure should be continually monitored. Dynamic risk assessments and subsequent analytical risk assessments based on the information received from the monitoring process can dictate additional control measures, and will provide personnel with information as to the working environment.
Personnel should be aware that some supplies may not have been located and made safe and, therefore, should not cut the following:
- Water pipes: flooding, or a sudden ingress of water, has been known to drown rescuers and casualties in flooded basements. The sound of flowing water can also interfere with the use of acoustic search equipment
- Gas pipes: gases leaking into a collapsed building can pool at lower levels such as basements, depending on the density of the gas
- Electrical cables or wires: experience has shown that other wiring (e.g. telephone cables) can become live after coming into contact with mains wiring
Stage 3: Primary surface search and rescue
At this point in the incident, it may be appropriate for the incident commander to withdraw all personnel and to assess progress made up to that point. It may also be appropriate for the incident commander to review the suitability of the ICS structure in place at that time. Consideration should be given to designating one or more specific search sectors dependent on the size of the incident, each of which should be nominated its own site identification number.
After ensuring rescuer safety and minimal movement of the debris, small organised teams should be deployed to search each sector systematically in specific grids. Canine search teams can be particularly effective in undertaking this task. An agreed marking scheme should be used to demonstrate visually the areas that have been searched, any areas of canine interest, and those areas that could potentially contain casualties. Care should be taken when using some methods of marking (e.g. spray paints) as these may interfere with ongoing canine search operations when indoors. The chosen method of marking should also consider the need for discretion where casualty locations are to be noted.
As many as half of all building collapse survivors have historically been rescued near the surface of the debris and early on in the operation. The initial search should be concentrated on those areas that are believed to be the last known locations of people when the collapse occurred. All surface casualties should be removed as quickly and safely as possible.
Extreme care should be taken during this phase to ensure that rescuers do not become casualties. Personnel should not be misled by the outward appearance of a structure; what appears to be a settled pile of debris could, in reality, be lacking any genuine support, and a secondary collapse could occur without warning.
Stage 4: Exploration of voids and spaces
All voids and accessible spaces created as a result of the collapse must be searched and explored for live casualties. An audible call-out system can be used during this phase. Only trained canine or rescue personnel should be used to search voids and accessible spaces. Voids should be explored visually, by canines and with technical search equipment.
Good practice dictates that at approximately every hour on the hour all work on the site be shut down for a few minutes to listen for calls for help. During that period sound detection devices can be used to listen for movement or sounds deep within the debris.
Stage 5: Access by selected debris removal
Selected debris removal using special tools and techniques may be necessary after locating a casualty. It may be necessary to remove only certain obstructions that are blocking access to the casualty. Information concerning a casualty's location prior to the collapse can be helpful during the selected debris removal phase. Information gathering on other possible casualty locations can greatly enhance the operation.
Stage 6: Terminate by general debris removal
General debris removal is usually conducted after all known casualties have been removed. Exceptions would be:
- When information is obtained that indicates the possibility of other casualties not originally accounted for
- When large amounts of debris are impairing or obstructing operations. The decision to use heavy equipment during this phase must be given serious consideration, especially when the possibility exists that there are still live casulaties in the debris
Involving other emergency services or appropriate resources and casualty care should be considered. Refer to the Casualty care section.
The incident commander, while developing their tactical plans, should take the following hazards that may be present following a structural collapse into account, and carry out a Dynamic Risk Assessment (DRA) that considers them:
- Incoming and/or damaged utilities. See National Operational Guidance: Utilities and fuel
- Sub-surface voids
- Underfoot conditions, including the unstable nature of surface (rubble). See National Operational Guidance: Operations
- Manual handling. See National Operational Guidance: Operations
- Secondary collapse
- Uncontrolled rescue attempts
- Secondary or further collapse as a result of wind, rain, vibration, etc.
- Intimidation or violence from casualties, etc.
- Noise levels. See National Operational Guidance: Operations
- Dust (airborne, static or caustic). See National Operational Guidance: Hazardous materials
- Damage to mass storage vessels
- Asbestos. See National Operational Guidance: Hazardous materials
- Obstructed, hidden or flooded voids
- Glass dust. Refer to the Extrication - Generic - Tools section
- Falling objects including glass
- Temperature-induced illness. See National Operational Guidance: Operations
- Arduous working conditions and physiological stress
- Hazardous materials (HazMat); irrespirable/hazardous atmospheres, explosives, flammable, toxic or biological materials/substances etc. See National Operational Guidance: Hazardous materials
- Environmental conditions such as darkness
- Fire, heat and smoke. See National Operational Guidance: Fires and firefighting
- Snagging, e.g. sharp edges from damaged building components, for example reinforcement bars
- Falls from height. See National Operational Guidance: Operations
Knowledge and understanding
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