Lifting bags: A simple job, or not?
We regularly hear or read in the news about accidents in which people become trapped under an object or a vehicle. This may be due to a collapsed building, a stack of shipping containers that has toppled, or a traffic accident involving a truck or a bus.
Freeing the victims often presents complex challenges for rescuers. How heavy is the object to be lifted, where do I start, and how can I approach the victim trapped under a (sometimes heavy) load?
The use of lifting bags
Virtually every rescuer is familiar with high-pressure lifting bags; they have been part of our equipment range for years. It is a strikingly simple tool – in short, a bag filled with air – but one that enables a huge range of applications.
I admit that when I think of the drills that we conduct with lifting bags in my own fire department – they're not always the most exciting moments. Still, it's good to pay sufficient attention when using lifting bags in a rescue so you can provide the victim with the help they need when it counts.
Lifting versus tilting
When we want to use lifting bags to create space during a rescue operation, we are often talking about lifting a load. However, it's rarely necessary to lift the entire load; usually the load is still partly in contact with the ground so when the load is being lifted, we try to make sure that this side maintains contact with the ground. Then you're not lifting but actually tilting.
In tilting, we only 'lift' part of the total weight. This is important when estimating the load that needs to be moved and the choice of a lifting bag with the right lifting capacity.
Example
Suppose that a victim has ended up under a car; in this case, the lifting bags are positioned on that side of the vehicle. The wheels on the side that the victim is on will rise, while the wheels on the other side of the car remain on the ground. When we lift in this way, we are actually tilting. If we opt to position lifting bags on both sides of the car, to raise all four wheels from the ground, then we're lifting.
In this last method – lifting – contact with the ground is largely lost, thus creating the possibility that the load will move sideways. So, a tilting action is often more stable (and therefore safer) than a lifting action.
Safety first
During a rescue operation the victim is, of course, always the main focus. If you're lifting a load in order to free someone who is trapped, this must be done under medical supervision due to possible complications (Crush Injury Syndrome). But lifting or tilting is a complex procedure – one where the focus should also be also on the safety of the rescuers.
High-pressure lifting bags can be inflated or deflated remotely, therefore it is not necessary for the rescuer to be close to the load. This means that the rescuer has a better view of the load and is better able to communicate with the rest of the rescue team. However, during a lifting operation, I also recommend that someone is always designated as the safety officer. This team member can focus entirely on the load and any movement that may occur. By allowing this designated safety person to have direct contact with the person operating the lifting bags, a failing situation can be quickly signaled and prevented. In any case, make sure a load is always lifted slowly and very carefully; a system that controls the airflow precisely can help.
Practical tips when using lifting bags
- Consider the type of load to be lifted. Can the load shift? This applies to freight in particular – for instance, liquids or sand and gravel.
- Find out what the load weighs or make a good guess, which certainly isn't easy. For building constructions, use a rule of thumb (i.e., 2,400 kg per m3 of concrete or 150 lbs. per cubic feet); a waybill or general knowledge can help to make an estimation for trucks.
- When choosing the lifting bags that you are going to use, consider not only the weight of the load and therefore the lifting capacity but also take into account the lifting height you need. The pressure gauge on all lifting bag systems indicates the relationship of the load to the maximum capacity of the bag. The lifting height is marked on the lifting bag, sometimes with a handy visual indicator.
- Make sure you have cribbing close by and position it immediately; cribbing ensures a safe work area. General rule: Lift an inch (2.5 cm), crib the inch (2.5 cm). Take note: Do not place your hands under the load when positioning the cribbing.
- Keep the initial opening for the lifting bag as small as possible, and position blocks under the bag if necessary. This ensures direct contact with the load when the lifting bag is inflated, which provides a larger contact surface for the lifting bag and makes the situation more stable. This way you utilize the full capacity of the lifting bags. Because the bag's lifting capacity decreases and its rounded shape increases as the bag is inflated, the load may become unstable.
- If the lifting height of one high-pressure lifting bag is not enough for your situation, bags can be stacked, but do take the following precautions:
- Never use more than two traditional lifting bags when stacking bags.
- Most lifting bags have a profiled surface that interlocks to prevent them from shifting position, so never put anything in between the bags.
- Use the largest lifting bag at the bottom for more stability. Remember that the maximum lifting capacity of the two bags together is that of the bag with the lowest capacity.
- For stable lifting, inflate the top bag first; when the bottom bag is inflated, it takes on the shape of a bowl and encloses the smaller top bag.
So, the load has been lifted: Now what?
If – after the load has been lifted and/or the victim has been freed – the load cannot remain on the cribbing, the load must be brought back down to the ground. The same safety measures apply here. Letting the load down is possibly even more risky than lifting it when rescuing the victim. Because the victim has been freed, it's easy to lose your focus on safety and control. The safety officer designated earlier will also play an important role in letting the load down. Make sure the cribbing is removed gradually; follow the load, keeping the gap between the load and the cribbing as small as possible.
Conclusion
Lifting bags are essential rescue equipment when moving heavy loads in a safe and controlled manner. Doing this correctly, however, requires the necessary attention. Assess the situation thoroughly: What kind of load is it, are we going to tilt or lift, and how much weight must be moved? If a victim needs to be freed, medical support is important to avoid complications. Safety comes first and foremost, so communication and the various roles of the team members are key. However, partly due to the great degree of control and the relatively safe position from which they are operated, lifting bags are one of the safest solutions for moving loads during a rescue operation.
I welcome your feedback in the comments.
Ronald de Zanger
Holmatro Rescue Consultant