|
|
|
|
|
24 January 2025
|
Featured FRI Magazine article: Managing vehicle underride extrications by Colin Deiner
When a light motor vehicle crashes into the side or rear of a heavy vehicle, a whole new challenge will present itself
Do you have sufficient lifting/shoring equipment to hold and lift these loads?
|
Lifting must be done in a controlled manner and any openings that get created must be filled by cribbing or airbags
|
Frame rails for large commercial vehicles are much higher and larger sized cribbing may be needed
|
Try before you pry but make sure that you are able to do it without making things worse
|
A high speed side-entry underride could cause the car to be trapped quite deeply under the heavy vehicle and the victim(s) might not be easily visible.
https://www.frimedia.org/uploads/1/2/2/7/122743954/fri_vol_3_no_1.pdf
This week’s featured Fire and Rescue International magazine article is: Managing vehicle underride extrications written by Colin Deiner, chief director, Disaster Management and Fire Brigade Services, Western Cape Government (FRI Vol 3 no 1). We will be sharing more technical/research/tactical articles from Fire and Rescue International magazine on a weekly basis with our readers to assist in technology transfer. This will hopefully create an increased awareness, providing you with hands-on advice and guidance. All our magazines are available free of charge in PDF format on our website and online at ISSUU. We also provide all technical articles as a free download in our article archive on our website.
Managing vehicle underride extrications
By Colin Deiner, chief director, Disaster Management and Fire Brigade Services, Western Cape Government
When rescue services are called to motor vehicle accidents involving a collision of a heavy motor vehicle against a light passenger vehicle, they could be confronted by a number of possible scenarios.
Unfortunately, none of them good.
Head on collisions will cause severe damage to the light motor vehicle and a high fatality rate is generally the result. There are seldom entrapments in such situations unless passengers are entangled in the wreckage of the vehicle due to the damage it suffered on impact.
When a light motor vehicle crashes into the side or rear of a heavy vehicle, a whole new challenge will present itself. The light motor vehicle might propel itself to some distance below the heavy vehicle’s chassis until it stops due to being wedged against the side or chassis of that vehicle. The car could also come into contact with a number of vehicle support components such as the fuel tank, battery casing or support beams. The components could be dislodged or break and cause additional threats to the victims and risks to the responding agencies.
These incidents often occur at night and in places where motorists don’t anticipate the presence of heavy vehicles. When during my career I have responded to such incidents, it has been at crossings or on freeways where heavy vehicles drivers have attempted to turn their vehicles across the road for some reason, change multiple lanes or has suffered some sort of mechanical failure and come to a standstill on a road surface. We have also all encountered the trailer ‘Jack-knife where a steering axle brake problem has caused a trailer to cause the two units to move laterally and end up being unrecoverable on their final stationary position.
Injuries in such cases are normally very severe and are mostly head (facial) and upper body injuries. You will also encounter lower limb entrapment if the dashboard of the victim’s vehicle is forced down by some component of the heavier vehicle. In rarer cases, vehicle components can get dislodged and penetrate victims causing more serious injuries.
When encountering a vehicle underride incident, a number of options might be available to the rescue commander, however, a thorough assessment of both the position and level of entrapment of the victim and the position of the vehicle will have to be done in order to determine the best method of release.
Response and scene safety
As we all know, the incident starts with the receipt of the call. If the despatcher ascertains that it is a heavy versus light motor vehicle incident, the correct resources need to respond immediately. A heavy rescue truck with a rotator boom, if available, should form part of the initial response. If your service does not have access to such a resource, an agreement should be in place with some local vehicle recovery companies who would be able to supply heavy recovery vehicles at short notice. You can always send it back if you don’t need it.
Also anticipate the possibility of a hazardous materials release. If the impact was on or near the heavy vehicle’s fuel saddle tank, you may have a negligible to significant release of diesel that will have to be controlled before any extrication work can be commenced. Fuel, which has found its way onto injured victims, will pose other problems that will need to be addressed. Hydraulic oil spills, oil tanks under pressure and leaking fuel lines must also be identified and secured.
Other than the vehicle’s internal systems, the type and capacity of the load being transported must be carefully noted. It has often happened in the past that rescue crews have conducted an epic vehicle underride extrication only to, at the end of it all, realise that they were working in close proximity to a highly-compromised compressed gas vessel or extremely toxic load. That’s why they have such good guardian angels.
The deployment of a hazmat team might be required before the rescue crew can enter the hot zone. They might be required to isolate a leaking valve or ripped surface and control the product that has already escaped from the load. A measure of decontamination might have to be done and it could also be possible that they will have to set up some sort of decontamination station once the rescuers and the patient exit the hot zone.
Among all the other generic safety considerations for a vehicle accident scene, you must also try to ascertain the location of the victim(s). A high speed side-entry underride could cause the car to be trapped quite deeply under the heavy vehicle and the victim(s) might not be easily visible.
Stabilisation
Most first responding rescue trucks carry sufficient shoring for one or two light motor vehicles. With this they are able to shore a car on its roof, side and all four wheels. Appreciate, however, that frame rails for large commercial vehicles are much higher and larger sized cribbing may be needed. This is not only for an increase in the required weight support but also to provide for the increased height needed for the larger box cribs. Always remember the minimum safety heights for airbags and their load carrying capacity. Please refer to ‘Working with airbags’, Fire and Rescue International, Vol 2 no 7 in 2013 for more information.
Before any vertical stabilisation is attempted, it is important to prevent any lateral movement of the vehicle(s). You should start by chocking any wheels that are still in contact with the ground. It is also important to strap down components of the vehicle or load that may move during the rescue phase.
Due to most of the cabs on these heavy commercial vehicles featuring body-mount assemblies that are either spring-loaded or pneumatic, it will be necessary for the cab load to be directed to the ground through the frame rails as well. To achieve this, you might need to insert cribbing between the frame rails and the underside of the cab always ensuring that your stabilisation will not be in the way (and therefore compromise) any metal relocation that will have to be done later on.
A side-entry underride against a lower frame vehicle with soft cladding such as a passenger bus or furniture truck, could obscure the driver’s seat of the light motor vehicle from the rescue team and will need a deeper penetration into the vehicle to understand the level of entrapment/patient condition. Cribbing the vehicle will be tricky and might be a ‘feel as you go’ exercise until some sort of stabilisation is achieved. Knowledge of the anatomy of such vehicles must form part of your vehicle rescue training programme in order for responders to understand where its ‘stabilisation contact points’ will be. Rescue units must have at least two air chisels (panel cutters) and sufficient air to remove parts of the cladding that may obscure vision and open areas needed for stabilisation contact points.
Knowing what the weight is that you will need to lift might entail a bit of ‘educated guesswork’. South Africa’s national road traffic legislation regulates the maximum vehicle’s permissible mass on public roads to 7,5- ton (single axle), 18-ton (double axle) and 24-ton (three axles). In most incidents, you will only need to raise the load a small distance and factors such as a shifted load, position of the vehicles and reach ability of rescue equipment will have an influence on your calculations. Pneumatic high pressure lifting bags have a lifting capacity generally higher than would be required.
The most important question you will have to answer is “do I have sufficient lifting/shoring equipment to hold and lift these loads?” This is not a question that you would want answer when you are confronted by it on scene.
When dealing with a trailer underride, the trailer’s landing gear will provide a significant amount of stabilisation support if it hasn’t been damaged and is able to be deployed. Also remember that landing gear is generally deployed in a controlled environment and on a stable surface. If you are going to deploy the landing gear on an unstable surface, ensure that you are able to stabilise the surface on which you are going to drop the gear. The truck’s baseplates will be ideal for this purpose.
Try before you pry
During a light passenger vehicle underride incident I attended a number of years ago, we were setting up for a major lifting operation to remove the load off the patient in the driver’s seat when one of the rescue crew grabbed hold of the seat’s adjustment handle and moved it backwards. The result: patient was freed and a whole lot of rescuers were left saying ‘why didn’t I think of that’. It can be that simple. If, however, the load is projected directly on the victim or a vehicle component has caused some sort of penetration, it would not be advisable. Try before you pry but make sure that you are able to do it without making things worse.
Controlled lift, controlled release
When you are lifting the truck/trailer off the smaller vehicle, you are, in effect, separating the two vehicles from each other. This must be done in a controlled manner and any openings that get created must be filled by cribbing or airbags. ‘Crib-as-you-go’ at least two points around the load. You might find that a fair amount of entanglement has taken place between the two vehicles and this might cause the light vehicle to be lifted (along with the truck/trailer) the moment the truck/trailer is raised. This can be caused by a number of factors such as frame rails, body supports, wiring or tubing. You may need to have a rescue crew on standby to cut these components away using hydraulic cutters or reciprocating saws. If this is not possible, you might have to allow the vehicle to lift together with the overhead load but at the same time making sure that it is done under control. It might, however, not assist in providing access to the victim.
You do not want rescuers working under the load. This movement will have to be very carefully monitored, all the time appreciating the path of access for the rescuers and egress of the patient. Rescues of this nature can be very taxing and also extend for quite a long time. All this must be taken into consideration and it will be necessary to plan for a more thorough level of patient care while the release is being performed.
Any lifting of the load will probably have a cantilever effect and here it is important to consider the load being carried. Solid loads, gases and liquids will react differently when they are displaced and could cause enough inertia to cause the load displacement in an opposite direction with adverse results. Any load carrying many smaller products (eg cold drinks) might have to be off-loaded before the lift can even be started.
Training
As a rescue trainer in a previous job, I used to be surprised at the number of requests I used to get for structural collapse training from fire and emergency services. The high level of technical competency in this field in South Africa has been proven with the exceptional response to a number of recent major structural collapse incidents occurring at various centres.
What always surprised me was the willingness of some services to acquire these skills for their staff at the cost of up-skilling them in the field of vehicle extrication. Vehicle extrication is the base from which all other heavy rescue techniques will develop.
I know vehicle wrecks are extremely hard to come by for training in this country (not to mention the availability of trucks). This does not prevent you from contacting your local transport company or trucking company and taking your crews to their premises to check out the various features that they might confront on a dark night when a car is trapped underneath it. In the early years of the Southern African Emergency Services Institute (SAESI) National Extrication Challenge, trailers formed part of each exercise pit and vehicle underride scenarios were regularly presented to rescue teams. This has sadly (due to logistical reasons) fallen by the wayside. I sincerely hope that organisers of this event, in future, will consider bringing this important feature back to the extrication challenge.
It is really at this point that management must get involved and budget for this need. Rescue services are judged by the public on their ability to rescue people. Open days, clean stations, medal parades and many other routine fire services activities mean nothing if the four man crew responding to the accident involving a slightly inebriated little Jimmy Brown and his mates at 03h00 on a Sunday morning are not able to remove him safely and effectively from the wreck of his mother’s car; ie services are judged on their ability to do their core jobs.
Rescue services management need to think outside of the box when it comes to providing realistic training resources to ensure the best possible responses to the emergencies in their jurisdictions. It should not be left to the odd enterprising staffer who just happens to have a ‘contact’ at the local junkyard.
This week’s featured Fire and Rescue International magazine article is: Managing vehicle underride extrications written by Colin Deiner, chief director, Disaster Management and Fire Brigade Services, Western Cape Government (FRI Vol 3 no 1). We will be sharing more technical/research/tactical articles from Fire and Rescue International magazine on a weekly basis with our readers to assist in technology transfer. This will hopefully create an increased awareness, providing you with hands-on advice and guidance. All our magazines are available free of charge in PDF format on our website and online at ISSUU. We also provide all technical articles as a free download in our article archive on our website.
Managing vehicle underride extrications
By Colin Deiner, chief director, Disaster Management and Fire Brigade Services, Western Cape Government
When rescue services are called to motor vehicle accidents involving a collision of a heavy motor vehicle against a light passenger vehicle, they could be confronted by a number of possible scenarios.
Unfortunately, none of them good.
Head on collisions will cause severe damage to the light motor vehicle and a high fatality rate is generally the result. There are seldom entrapments in such situations unless passengers are entangled in the wreckage of the vehicle due to the damage it suffered on impact.
When a light motor vehicle crashes into the side or rear of a heavy vehicle, a whole new challenge will present itself. The light motor vehicle might propel itself to some distance below the heavy vehicle’s chassis until it stops due to being wedged against the side or chassis of that vehicle. The car could also come into contact with a number of vehicle support components such as the fuel tank, battery casing or support beams. The components could be dislodged or break and cause additional threats to the victims and risks to the responding agencies.
These incidents often occur at night and in places where motorists don’t anticipate the presence of heavy vehicles. When during my career I have responded to such incidents, it has been at crossings or on freeways where heavy vehicles drivers have attempted to turn their vehicles across the road for some reason, change multiple lanes or has suffered some sort of mechanical failure and come to a standstill on a road surface. We have also all encountered the trailer ‘Jack-knife where a steering axle brake problem has caused a trailer to cause the two units to move laterally and end up being unrecoverable on their final stationary position.
Injuries in such cases are normally very severe and are mostly head (facial) and upper body injuries. You will also encounter lower limb entrapment if the dashboard of the victim’s vehicle is forced down by some component of the heavier vehicle. In rarer cases, vehicle components can get dislodged and penetrate victims causing more serious injuries.
When encountering a vehicle underride incident, a number of options might be available to the rescue commander, however, a thorough assessment of both the position and level of entrapment of the victim and the position of the vehicle will have to be done in order to determine the best method of release.
Response and scene safety
As we all know, the incident starts with the receipt of the call. If the despatcher ascertains that it is a heavy versus light motor vehicle incident, the correct resources need to respond immediately. A heavy rescue truck with a rotator boom, if available, should form part of the initial response. If your service does not have access to such a resource, an agreement should be in place with some local vehicle recovery companies who would be able to supply heavy recovery vehicles at short notice. You can always send it back if you don’t need it.
Also anticipate the possibility of a hazardous materials release. If the impact was on or near the heavy vehicle’s fuel saddle tank, you may have a negligible to significant release of diesel that will have to be controlled before any extrication work can be commenced. Fuel, which has found its way onto injured victims, will pose other problems that will need to be addressed. Hydraulic oil spills, oil tanks under pressure and leaking fuel lines must also be identified and secured.
Other than the vehicle’s internal systems, the type and capacity of the load being transported must be carefully noted. It has often happened in the past that rescue crews have conducted an epic vehicle underride extrication only to, at the end of it all, realise that they were working in close proximity to a highly-compromised compressed gas vessel or extremely toxic load. That’s why they have such good guardian angels.
The deployment of a hazmat team might be required before the rescue crew can enter the hot zone. They might be required to isolate a leaking valve or ripped surface and control the product that has already escaped from the load. A measure of decontamination might have to be done and it could also be possible that they will have to set up some sort of decontamination station once the rescuers and the patient exit the hot zone.
Among all the other generic safety considerations for a vehicle accident scene, you must also try to ascertain the location of the victim(s). A high speed side-entry underride could cause the car to be trapped quite deeply under the heavy vehicle and the victim(s) might not be easily visible.
Stabilisation
Most first responding rescue trucks carry sufficient shoring for one or two light motor vehicles. With this they are able to shore a car on its roof, side and all four wheels. Appreciate, however, that frame rails for large commercial vehicles are much higher and larger sized cribbing may be needed. This is not only for an increase in the required weight support but also to provide for the increased height needed for the larger box cribs. Always remember the minimum safety heights for airbags and their load carrying capacity. Please refer to ‘Working with airbags’, Fire and Rescue International, Vol 2 no 7 in 2013 for more information.
Before any vertical stabilisation is attempted, it is important to prevent any lateral movement of the vehicle(s). You should start by chocking any wheels that are still in contact with the ground. It is also important to strap down components of the vehicle or load that may move during the rescue phase.
Due to most of the cabs on these heavy commercial vehicles featuring body-mount assemblies that are either spring-loaded or pneumatic, it will be necessary for the cab load to be directed to the ground through the frame rails as well. To achieve this, you might need to insert cribbing between the frame rails and the underside of the cab always ensuring that your stabilisation will not be in the way (and therefore compromise) any metal relocation that will have to be done later on.
A side-entry underride against a lower frame vehicle with soft cladding such as a passenger bus or furniture truck, could obscure the driver’s seat of the light motor vehicle from the rescue team and will need a deeper penetration into the vehicle to understand the level of entrapment/patient condition. Cribbing the vehicle will be tricky and might be a ‘feel as you go’ exercise until some sort of stabilisation is achieved. Knowledge of the anatomy of such vehicles must form part of your vehicle rescue training programme in order for responders to understand where its ‘stabilisation contact points’ will be. Rescue units must have at least two air chisels (panel cutters) and sufficient air to remove parts of the cladding that may obscure vision and open areas needed for stabilisation contact points.
Knowing what the weight is that you will need to lift might entail a bit of ‘educated guesswork’. South Africa’s national road traffic legislation regulates the maximum vehicle’s permissible mass on public roads to 7,5- ton (single axle), 18-ton (double axle) and 24-ton (three axles). In most incidents, you will only need to raise the load a small distance and factors such as a shifted load, position of the vehicles and reach ability of rescue equipment will have an influence on your calculations. Pneumatic high pressure lifting bags have a lifting capacity generally higher than would be required.
The most important question you will have to answer is “do I have sufficient lifting/shoring equipment to hold and lift these loads?” This is not a question that you would want answer when you are confronted by it on scene.
When dealing with a trailer underride, the trailer’s landing gear will provide a significant amount of stabilisation support if it hasn’t been damaged and is able to be deployed. Also remember that landing gear is generally deployed in a controlled environment and on a stable surface. If you are going to deploy the landing gear on an unstable surface, ensure that you are able to stabilise the surface on which you are going to drop the gear. The truck’s baseplates will be ideal for this purpose.
Try before you pry
During a light passenger vehicle underride incident I attended a number of years ago, we were setting up for a major lifting operation to remove the load off the patient in the driver’s seat when one of the rescue crew grabbed hold of the seat’s adjustment handle and moved it backwards. The result: patient was freed and a whole lot of rescuers were left saying ‘why didn’t I think of that’. It can be that simple. If, however, the load is projected directly on the victim or a vehicle component has caused some sort of penetration, it would not be advisable. Try before you pry but make sure that you are able to do it without making things worse.
Controlled lift, controlled release
When you are lifting the truck/trailer off the smaller vehicle, you are, in effect, separating the two vehicles from each other. This must be done in a controlled manner and any openings that get created must be filled by cribbing or airbags. ‘Crib-as-you-go’ at least two points around the load. You might find that a fair amount of entanglement has taken place between the two vehicles and this might cause the light vehicle to be lifted (along with the truck/trailer) the moment the truck/trailer is raised. This can be caused by a number of factors such as frame rails, body supports, wiring or tubing. You may need to have a rescue crew on standby to cut these components away using hydraulic cutters or reciprocating saws. If this is not possible, you might have to allow the vehicle to lift together with the overhead load but at the same time making sure that it is done under control. It might, however, not assist in providing access to the victim.
You do not want rescuers working under the load. This movement will have to be very carefully monitored, all the time appreciating the path of access for the rescuers and egress of the patient. Rescues of this nature can be very taxing and also extend for quite a long time. All this must be taken into consideration and it will be necessary to plan for a more thorough level of patient care while the release is being performed.
Any lifting of the load will probably have a cantilever effect and here it is important to consider the load being carried. Solid loads, gases and liquids will react differently when they are displaced and could cause enough inertia to cause the load displacement in an opposite direction with adverse results. Any load carrying many smaller products (eg cold drinks) might have to be off-loaded before the lift can even be started.
Training
As a rescue trainer in a previous job, I used to be surprised at the number of requests I used to get for structural collapse training from fire and emergency services. The high level of technical competency in this field in South Africa has been proven with the exceptional response to a number of recent major structural collapse incidents occurring at various centres.
What always surprised me was the willingness of some services to acquire these skills for their staff at the cost of up-skilling them in the field of vehicle extrication. Vehicle extrication is the base from which all other heavy rescue techniques will develop.
I know vehicle wrecks are extremely hard to come by for training in this country (not to mention the availability of trucks). This does not prevent you from contacting your local transport company or trucking company and taking your crews to their premises to check out the various features that they might confront on a dark night when a car is trapped underneath it. In the early years of the Southern African Emergency Services Institute (SAESI) National Extrication Challenge, trailers formed part of each exercise pit and vehicle underride scenarios were regularly presented to rescue teams. This has sadly (due to logistical reasons) fallen by the wayside. I sincerely hope that organisers of this event, in future, will consider bringing this important feature back to the extrication challenge.
It is really at this point that management must get involved and budget for this need. Rescue services are judged by the public on their ability to rescue people. Open days, clean stations, medal parades and many other routine fire services activities mean nothing if the four man crew responding to the accident involving a slightly inebriated little Jimmy Brown and his mates at 03h00 on a Sunday morning are not able to remove him safely and effectively from the wreck of his mother’s car; ie services are judged on their ability to do their core jobs.
Rescue services management need to think outside of the box when it comes to providing realistic training resources to ensure the best possible responses to the emergencies in their jurisdictions. It should not be left to the odd enterprising staffer who just happens to have a ‘contact’ at the local junkyard.