Multi-Purpose Device Simplifies Rope Rescue

By Raul A. Angulo

One of my favorite cartoons is by Deputy Chief Gary English, the Seattle (WA) Fire Department (SFD) assistant fire marshal. The cartoon shows a group of five or six firefighters with all their gear and equipment standing in a circle looking down into a giant manhole. The caption reads, “You know, we would have been able to save you before we were trained.” Isn’t that the truth!

I remember a call we had when I was on Engine 33. My crew was dispatched to a drowning on Lake Washington. The victim was about 14 years old and ended up going down in about seven feet of water 40 feet from shore. I tied a rope around my lead firefighter and handed him my swimming goggles. We saved the kid, but he died 10 days later. There were some chiefs who wanted to formally reprimand us for violating the policy against free diving and for not waiting for the dive team. I asked those guys, “How long did you expect this kid to hold his breath?”

I recently watched a few seasons of Emergency! In one rescue, Johnny and Roy had a patient over the beach cliffs. The crew anchored the rope to the front bumper hooks of Engine 51 and threw the coil of rope over the cliff. Johnny and Roy both took a couple of wraps around the hook of their ladder belts and rappelled down to the patient. Chet and Marco sent the equipment and the Stokes basket down on another line. The two paramedics treated and packaged the patient. Engineer Stoker put the apparatus in reverse and towed everyone back up to safety-simple and fast.

Pictured are the Traverse Rescue 540 Rescue Belay (left) and the CMC Multi-Purpose Device (MPD)

(1) Pictured are the Traverse Rescue 540 Rescue Belay (left) and the
CMC Multi-Purpose Device (MPD) (right). The rope-loading diagram
is etched into the face plate of the 540 for easy rigging. The rope can
be loaded from either end by taking 1½ wraps around the oval-shaped
pulley or 540 degrees. The orange parking brake dial in the center of
the MPD is one of the safety devices that can be set in case the
operator needs to leave his position, locking the load in place. It is
used in conjunction with the secondary friction post. (Photos by
author.)

 

My, how we’ve complicated this evolution! Now we need Class III harnesses, a main line, a belay line, travel limiters, prusiks, anchor plates, anchor straps, brake racks, carabiners, and pulleys. We have to know how to tie water knots, interlocking long-tail bowlines with a Yosemite finish, a double figure eight, and the infamous Munter hitch. We have positions like attendant, controller, and safety and commands like, “Attendant ready? Main line ready? Belay ready? Up, up! Down, down! Stop!” Oh yeah, now we’re not supposed to say “slack” anymore, just up or down. How are we supposed to remember all this when this is a high-risk/low-frequency event?

That’s what this job is all about and why we train hard-to get it right for an event that may never happen in our career. As a captain of a ladder company, there’s no evolution that puts more pressure on me than technical rope rescue. There are so many moving parts to this evolution. The crew is working independently to set up all the components and the person who gets the least “hands on”-the company officer-is the one who has to make sure and check that the system is set up correctly. He has to make sure every knot is tied correctly and all the rigging is as it should be.

This view shows the secondary friction post, the movable brake, and the load-release lever.

(2) This view shows the secondary friction post, the movable brake,
and the load-release lever.

 

One Device for Lifting and Lowering

A recent innovation in confined space and rope rescue is the Multi-Purpose Device (MPD) from CMC Rescue. The MPD allows rescuers to go from a lowering system to a raising system with the turn of a handle. More than nine years of research and development went into the patented MPD. The MPD is a high-efficiency pulley with an integral rope-grab mechanism, which means it can be used as a lowering device on the main line and belay line systems and be quickly changed over to a raising system without switching out hardware. The combination of these essential features into a single device simplifies on-scene rigging, expediting the rescue. It increases user safety with reduced weight, fewer components, faster rigging, quick changeovers, lower risk, and simplified training.

The MPD is UL-classified to be used as a pulley, a belay device, an auxiliary device, and a variable descent control device for rescue systems and rappelling. It incorporates a high-efficiency pulley with an integral rope-locking mechanism-or a ratchet-so it can be used as both a lowering brake and as a ratcheting pulley for a hauling or raising system. The built-in becket allows cleaner rigging for a more efficient pulley system. This makes the MPD suitable for confined space operations because it quickly converts to a retrieval line.

Shown here are the orange load release lever and the high-efficiency pulley with the one-way bearing for raising evolutions

(3) Shown here are the orange load release lever and the high-
efficiency pulley with the one-way bearing for raising evolutions. The
movable brake is on the pulley. This also shows the fixed brake with
the “V” groove.

 

The MPD is compliant with NFPA 1983, Standard on Life Safety Rope and Equipment for Emergency Services, (2006 ed.) and meets the British Columbia Council for Technical Rescue (BCCTR) rescue belay competency criteria. The BCCTR competency drop test specifies that an appliance needs to catch a three-foot drop (1 meter) of a 617-pound (280-kg) rescue-sized load onto 9½ feet (3 meters) of kernmantle rescue rope with less than one meter of additional travel and less than 15 kilonewtons (kN) of force. For a general-use rated device, a 280-kg load and 12.7-mm rope are generally used. For a technical device, a 200-kg load (401 pounds) and 11-mm rope are used.

The MPD comes in two models. The 11-mm model accepts 11-mm (7⁄16-inch) rope. It has a slate-colored body. It is NFPA-compliant as a pulley, a belay, and descent control for technical use (3 Sigma MBS descent control 20 kN, 4,496 LBF).

The rope load diagram is also etched onto the face plate of the MPD showing the load end of the rope and hand position

(4) The rope load diagram is also etched onto the face plate of the
MPD showing the load end of the rope and hand position. It is nearly
impossible to load the rope incorrectly. If by chance the MPD is
loaded incorrectly, it will not pass the system safety check, which is
giving a sharp tug on the load side of the rope. The sharp tug should
capture and lock the load within the device.

 

The SFD System

The model the SFD selected was the 13-mm model, which accepts 13-mm (½-inch) rope. It comes in a red-colored body and weighs two pounds, 10 ounces (1.2 kg). This model is NFPA-compliant as a pulley, a belay, and descent control for general use (3 Sigma MBS pulley, 44 kN, 1,891 LBF and 3 Sigma MBS Descent Control, 23 kN, 5,170 LBF).

The MPD comes with a padded Cordura® nylon storage bag and user’s manual. It allows the main line and belay line rigging to be mirror images of one another. In other words, you can use two MPDs, one for each line. However, we discovered that there is a very slight, remote chance during a lowering evolution that the main line attendant and the belay line attendant can, in theory, have both MPDs open at the exact same time. For that moment, the load on the main line can free fall without arrest until someone lets go of an MPD. Once you let go of the MPD (hands free), it will immediately capture the load. For this reason, we chose not to use two MPDs at the same time and will continue to use the Traverse Rescue 540 Rescue Belay appliance on the belay line (see sidebar).

(5) This is a close-up of the operator lifting and maintaining the load
release lever. This is all that needs to be done to switch from a raise to
a lowering system.

 

More Safety Features

Other safety control features on the MPD include a load release handle, which does not engage unless you lift up on it and tend it. This prevents releasing the load because of accidental bumping. The parking brake, when set, allows the operator to leave his position; the load is tensioned and will not move. There is a fixed brake with the “V” groove, a movable brake, and the secondary friction post, all designed to control the lowering of or holding of the load. In the event the hauling team loses control of the load, the MPD engages the internal ratchet, applying friction to the rope, and arrests the fall.

Here the rope is in the maximum friction position

(6) Here the rope is in the maximum friction position. It is locked with
the secondary friction post holding the load position. If the parking
brake were to be set with a backup knot on the mainline at the MPD,
the operator could leave his position if the incident required it. The
patient and the rescuer would be safely secured. The 540 belay would
be the backup safety line.

 

Setting up the mechanical advantage using an MPD is quick and easy. On a standard raise and lowering system, it can replace the anchor plate, a descent control device-like a bar rack, a load release, a change of direction pulley, and a prusik. That’s eliminating at least 10 pounds of equipment.

Johnny and Roy made confined space and rope rescue look quick, simple, and easy. I’m not knocking the current safety and redundant systems. I realize they’re there for our safety and that many were introduced as the result of an accident where a rope system failed. I am saying they can be intimidating for company officers and crews when they don’t get ample opportunity to practice using them. Finally, someone came up with a truly innovative device to simplify the bread-and-butter rope system while maintaining the safety advantages in redundant systems. I was amazed at how easy the rope system was rigged using the MPD. I predict it will soon become a standard-issue device for rope rescue. It’s a clean setup and easy to see if everything is assembled correctly. It’s certainly going to make my job easier when, after a quick inspection, I’ll be able to say, “We’re good to go.”

This picture shows a raising evolution

(7) This picture shows a raising evolution. While the rescuer is being
lowered over the edge to the patient, the MPD operator is tending the
load-release lever. To change to a raising system, the operator simply
needs to let go of the lever. In fact, during a raise, the MPD doesn’t
even need to be attended. The high-efficiency pulley with one-way
bearing is designed to ratchet up freely while pulling up the load. If for
some reason the haulers were to suddenly release the rope, the MPD
would seize up immediately and capture the load. You do not need to
switch out any appliances to change from a lower to a raise. The 3:1
mechanical advantage can be set up ahead of time and can be
maintained while lowering the load.

 

RAUL A. ANGULO, a veteran of the Seattle (WA) Fire Department and captain of Ladder Company 6, has more than 30 years in the fire service. He is a member of the Fire Apparatus & Emergency Equipment editorial advisory board. He lectures on fire service leadership, company officer development, and fireground strategy and accountability throughout the United States, Canada, and Mexico.


The 540° Rescue Belay Device

Traverse Rescue (a Ferno Group Company) engineered the 540° for fire service and industrial rescue teams. The symmetric design of the 540° allows bidirectional loading and locking-that means either end of the rope exiting the device may be used as a load line. This reduces the risk of improperly loading the device and increases operator efficiency. The device is UL-certified to ANSI and NFPA 1983 for general use and passes the demanding BCCTR belay competence drop test.

The 540° has an integrated release lever, eliminating the need for a separate release device or hitch. Decreasing complexity reduces rigging time and reduces the chance for system error. With the 540°, the tension of a locked-up belay is simply transferred back to the mainline by using a built-in release lever. It is very simple to use and reduces training time.

The 540° has a minimum breaking strength of 9,000 pounds. It self-locks with sudden falls and is designed to limit the “relative worst case scenario fall” of a rescue load to a peak force of approximately 15 kN or less with no more than about one meter of stopping distance. It accepts 11.5- to 13-mm-diameter kernmantle rescue rope. It’s advantageous to use a “static kernmantle” rescue rope with lower stretch properties. Note that kernmantle rope is rope constructed with its interior core (the kern) protected by a woven exterior sheath (mantle) designed to optimize strength, durability, and flexibility. The core fibers provide the tensile strength of the rope, while the sheath protects the core from abrasion during use. The name is derived from the German word kernmantel, which means core jacket.

The 540° gets its name from the way you load it. You wrap the rope around the oval-shaped pulley 1½ times, or 540°. The wraps may start from either side of the pulley, which makes it almost impossible to load incorrectly. A diagram of how to load the rope is etched on the front plate, which takes all the guesswork out of threading the device. The 540° weighs 24 ounces (680 grams) and has a one-year warranty.

The MPD also has the rope loading diagram etched on the face plate, making it easy to thread the rope into the device. It clearly illustrates the hand position and the load side of the MPD. Again, it’s almost impossible to load the device incorrectly. If for some reason a firefighter does manage to load the rope incorrectly, the 540° or the MPD will not pass the safety check. The safety check for the 540° is sharply pulling the rope from either end. The 540° will lock up and capture the load. On the MPD, giving a sharp tug to the load side of the rope will lock up the rope within the device.

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