Structural tower rescue


CarolinaFireJournal - By Adam Snyder
By Adam Snyder
01/10/2013 -

(This is part three of a three part series on structural tower rescue.)

Last issue we focused our discussion on structural tower management to include tower related emergencies and medical considerations. We also talked about the importance of proper preparation for tower climbing and associated fall protection. In this final article we are going to get into the meat and potatoes of structural tower rescue. We will be discussing tower based and ground based rescues.

Let’s look at the key concepts and factors that assist in the determination of a ground based or structure based rescue:

Structure-Based Rescues

Tower Height
Structure based rescues can be done at any height. The only limitation the rescue team may have is the length of life safety rope that is immediately available. 

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A skate block is a small pulley with a short webbing sling attached to the victim’s harness.

The concept of a ground-based rescue is that the fixed brake (lowering device) is anchored to the bottom of the tower with a webbing sling. The rope then travels parallel to the ground to a ground change of direction which could be your fire apparatus. The rope then travels upward to an elevated change of direction above the victim and then attaches to the victim. This allows the two rescuers on the tower to focus on the victim and the safety belay.

If the length of rope used is shorter than the lower the team may have to conduct an evolution, I refer to it as “hop scotch.” I will discuss this technique more later on.

Team Size
In structure based tower rescue the rescue team size is limited on the tower. It may only take two rescuers to perform victim removal.

Equipment Requirements
Limited rope equipment is needed as the rescuers are practically setting up a simple lower and belay system.

Ground-Based

Tower Height
Ground based rescues are limited to less than 150 feet. This limitation is due to the length of rope that is available and the limited ground space.

Team Size
This type of rescue requires a rigging/rescue team on the tower and on the ground. This type of rescue may require the use of six trained rescuers.

Equipment Requirements
Ground based rescue involve more complex rigging and equipment.

As you can see there are advantages and disadvantages of both types of rescue locations. The biggest determination should be what type of rescue (ground based or structure based) is the safest for the victim and rescuers.

Now that you have the basic concept and limitations between both ground-based and structure-based rescues let’s focus our attention to the lowering devices that we will use. These devices can also be referred to as brakes. These brakes can be used in two positions, one being the traveling brake and the other a fixed brake.

A traveling brake travels with the rescuer or victim such as when a rescuer is rappelling a fixed line. The traveling brake is great for structure based pick-off. Some examples of traveling brakes are the brake bar rack, Petzl ID, Petzl Stop.

This Petzl ID is an example of a fixed brake.

A fixed brake is a friction device that is located at a stationary anchor to lower a victim or rescuer. A fixed brake can be utilized in a structure-based or ground-based rescue. It all depends on the location of the fixed brake relevant to the tower. Some examples of fixed brakes are brake bar rack, CMC MPD and Petzl ID.

We’ve covered lowering devices used for structural tower rescue so let’s now talk about what we will use for belay devices. The easiest way to operate the belay device for structure-based or ground-based rescue is from the tower and above the victim location. This allows the least amount of rope in use and also allows the belayer full view of the victim. Some of the most common devices utilized for this type of belay is the CMC 540 or tandem triple wrap prusiks.

At times it is imperative to haul the victim up before lowering them. This might be due to an obstruction or to relieve the tension of the victim’s fall arrest device. This can be done in several ways.

The haul system utilized will be dependent on if it is a structure-based or ground-based rescue. For instance, if it is a ground based rescue the rescuers on the ground could perform a maneuver called “vectoring” which allows rescuers to grab the line between the anchor and ground change of direction. The rescuers would then walk forward holding the rope in the location of their hips. This will lift the victim approximately five or so feet.

Another system utilized is using a micro 4:1 between the fixed brake and anchor point. This will allow the rescuers to use the 4:1 to raise the victim.

A third option involves using an in-line pulley system utilizing the Petzl ID or CMC MPD. For structure-based rescues the rescuer is limited in using the micro 4:1 between the elevated anchors and lowering device as a means to haul the victim up temporally.

Now that we understand the equipment that we will use as lowering devices — hauling and belay devices — we discuss the specific operations to rescue a victim from a structural tower rescue. Please note that these techniques are for your information and hands-on training should be performed with a certified instructor prior to conducting these types of rescues. Also, we will not be discussing climbing systems during this article as that was discussed in the second part of this series.

The first thing that must be done is to pre-rig as much of the rescue system as possible on the ground. This will eliminate the amount of work and lessen the fatigue of the rescuers on the tower. Many of the systems can also be hauled up to the rescuer from the ground by the ground based team. This will limit the amount of weight the rescuer must climb with and also decrease the risk to the rescuer.

Let’s first look at a structure-based rescue with a simple top fixed brake. This is probably the most common type of rescue and most familiar to the rescuer.

During this type of rescue the rescue team would be comprised of two rescuers. Rescuer one would manage capturing the victim to prevent further injury and also hooking up and managing the lowering device (fixed brake). Rescuer two would manage the belay device. Both the fixed brake and the belay device shall be located above the victim on a secure anchor such as the tower lattice. Depending on the shape of the tower, a tag line may need to be attached to the victim to tag them away from the tower. Again, this type of lower is the bread and butter of our rope rescues. I have mentioned before the term “Hop Scotch” which in essence is exactly what it means. At times we may be conducting rescues on towers in excessive of 300 to1000 feet.

In this example of a skate block the pulley is running along the elevated line skating the victim from the tower as he is being lowered.

We may not have the rope requirements to conduct a straight lower. To conduct this type of rescue we may need to lower the victim to a certain location on the tower, secure him or her and then have the rescue team climb down to that location and reset the lowering system. This may be a very long process but might be your only option. Remember, if your victim is a clinging victim with no harness or fall restraint device, you as the rescuer need to provide one and secure the victim as soon as possible. If the victim is hanging and you as the rescuer cannot physical reach the victim from the tower you may have to conduct a pick-off which will require you as the rescuer to find an elevated anchor point and secure the rappel line. Then the rescuer can rappel down to the victim while a second rescuer operates an elevated belay. Once the rescuer makes contact with the hanging victim the rescuer must capture the victim and create a mechanical advantage to lift the victim off his/her system. The rescuer then can lower him/herself with the victim to the ground. As you can see in all three of the above structure-based tower rescue situations you may only need two rescuers on the tower to conduct the rescue safely.

There are specific techniques utilized in ground based rescues. First of all this type of operation requires several people, as mentioned before. You must have a rigging/rescue team on the tower and a rigging/rescue team on the ground. In ground-based rescue operations all of the hauling and lowering are done by the ground based team. You must also note that the length of rope utilized in ground based rescues must be 2.5 times the height of were the victim is located to the bottom of the tower. This is why most of the time we are limited to 150 feet for ground-based rescues.

The concept of a ground-based rescue is that the fixed brake (lowering device) is anchored to the bottom of the tower with a webbing sling. The rope then travels parallel to the ground to a ground change of direction which could be your fire apparatus. The rope then travels upward to an elevated change of direction above the victim and then attaches to the victim. This allows the two rescuers on the tower to focus on the victim and the safety belay.

Depending on the shape and design of the tower the victim may be lowered straight down. If the tower is wider at the bottom then the top the rescuer may choose to use a “skate block” to direct the victim away from the tower while being lowered. A skate block is a small pulley with a short webbing sling attached to the victim’s harness.

The pulley is running along the elevated line skating the victim from the tower as he is being lowered. In essence this line is acting as a track line. This technique is very effective and can be utilized with a single victim in a harness or stokes basket. The benefit to the ground-based rigging system with a stokes basket is that the stokes basket and all equipment can be hoisted up by the ground-based rigging team. This allows the rescue team on the tower to focus on packaging the victim and operating the safety belay. This type of operation is very complex and should be practiced by all members of the rescue team.

As we close out this series of articles we have covered many components of structural tower rescue to include: Structural tower awareness, construction characteristics, structural tower access and tower hazards. We also discussed the incident planning phase of structural tower rescue to include preparations for climbing and associated fall protection. Then we ended the series with the operational aspects of structure based and ground based rescues. During this series of articles we have just hit the surface of this rescue discipline and further instruction should be seeked out and conducted by experienced instructors who specialize in this type of complex rescue.

Adam Snyder has served over 18 years in emergency services. He is currently the Fire/Rescue/ EMS Chief for the Town of Atlantic Beach Fire Department in N.C. Snyder is a Fire and Rescue Instructor. He holds a degree in Fire Protection Technology and Emergency Medical Science. He is also a live fire instructor for acquired structures and LP gas. Snyder is also the founding member of and serves as the Pipe Major for the Eastern Carolina Firefighters Pipes and Drums Band. He can be reached at [email protected].
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  3/28/2013 7:59:50 AM
Daniel Davis 


Belay Device Correction 
In the paragraph covering belay devices the author states the "cmc 540". The 540 is not manufactured by cmc. The Canadian company of Traverse Rescue is the actual manufacturer of the 540 belay device.

Issue 34.1 | Summer 2019

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