We all have our personnel preferences as to what we like to use, or we like to use the same equipment we have made do with for many years without problems in the past, or maybe because that is the only equipment carried on our appliances. This is a page to broaden our thoughts on what and why we do things and why we use the same old equipment.
What is vehicle stabilisation: Vehicle stabilisation is the prevention or stopping of any movement in any direction of a vehicle following a collision where a casualty is still in situ, or in some cases there may be no one in the vehicle but it has landed in a precarious position which could put others at risk from further movement.
After an impact the vehicle will be in contact with the ground in some form or another and the area in contact with the ground can be measured in square inches, the idea of stabilising the vehicle is to increase the surface area in contact with the ground by the use of various pieces of equipment such as step blocks, blocks and wedges, Acro props and various types of hydraulic systems.
An example of such equipment can be seen in the above diagrams.
There is often some debate with regards as to what to use, in this case we will look at a vehicle on its wheels. Do we use step blocks or small blocks and wedges. Lets look at some of the advantages and disadvantages.
StepBlocks Blocks and Wedges
|
Advantages |
Disadvantages |
Advantages |
Disadvantages |
|
Quick and easy
|
Can create a trip hazzard |
Creates a very sturdy base |
Takes a bit longer to use than step blocks |
|
Can chock a large gap |
If used upside down tend to slide out |
Sits nicely under the vehicle out of the way |
Limited by the number carried |
|
Can be interlocked |
Will still need a wedge to fit tightly |
Can be used in small spaces |
Many are needed to fill the larger gaps |
|
Used either upright or upside down |
Easily knocked whilst working around them |
Reduces a trip risk |
|
|
|
If not thought out, they can compremise the extrication plan by becoming an obstruction |
|
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The above is just a list of some of the differences between the uses of the two, and is aimed to give you something to bear in mind, remember they are both very useful in the right environment and can complement each other greatly. Obviously the situation will dictate what we use to best stabilise the vehicle, in some rare occasions it may mean using other pieces of equipment all together, a way of thinking is that the vehicle is either stabilised or it isn't, regardless of what we use. However once we have stabilised the vehicle it is not good practice to have to remove blocks etc during the extrication, unless the type of techniques to be used have considered this as part of the plan, and not through bad planning and having to remove the blocks by misadventure.
As with all RTC's there is a time issue and this must not be overlooked by over cautious stabilisation techniques, keep it simple and fast but use the right equipment for the situation you are faced with.
You can see in the above pictures the difference between the two types of equipment used with regards to trip hazards etc. Both sides stabilised ready for a dash roll. You can see on the left picture that there is also a risk that the rear door may come into contact with the rear step block, it would perhaps have been better placed at an angle, and this picture is just for training purposes.
Do we use a step block upside down for speed and to remove the need to use a small wedge? This is a regularly visited topic and has been observed many times at incidents.
The step block is designed to be used the right way up for best results but as we all know can also be used upside down for many other situations, but in this context we are looking at a vehicle on its wheels.
If used upside down, already we are not increasing the surface area of the vehicle with the ground because the vehicle is just touching the angle of the step block, instead of the flat step if it where the right way up. There is also a greater risk from the step block sliding out from under the vehicle.
Do we just use them in this way for ease and speed, or because we don't want to spend those few extra seconds using it the right way up with a wide wedge, yes a wide wedge is used
because with a narrow wedge we again are not maximising the amount of surface area in contact with the ground. Again we may not carry enough wedges so we may well have to make do with a narrow wedge or perhaps use two narrow wedges next to each other, as with everything in the fire service we may have to improvise with the equipment we have available at the time.Another very good use for a step block is to put one under the rear of the vehicle in the area of the spare tyre; this offers extra stability where a casualty is being removed out over the luggage area of the vehicle.
Next time we will look at stabilising a vehicle on its side and roof.