During an access and evacuation drill, my team and I climbed 130 feet up a water tank. We then climbed another 30 feet to the tank’s domed top to remove an “ill worker.” The usual wind conditions were accompanied by muttered comments like, “My arms are killing me.”
The plan was simple: Package the patient in a Sked and lower him and an attendant over the edge and past the fixtures and cables on the side of the tank. The team made its assignments and started rigging, which initially went well. But as discussed in previous articles, neatness counts. Rope and gear strewn about like they’re part of a yard sale can make it difficult to quickly perform a system safety check and can increase trip and tangle hazards in an already risky environment (sloped footing). That, coupled with personal travel-limiting lines for those operating without a handrail, makes for a cluttered mess.
To make matters worse, Mikey, the litter attendant, attempted a long-tail bowline three times before successfully achieving one. As he attached himself to the line, another rescuer inquired if the 20′ tail was really needed. Mikey hastily replied that it would be fine and promptly stuffed the tail into the Sked to keep it from getting under foot.
The lowering system was a six-bar brake rack with a tandem prusik belay. At my department, the standard length for rescue ropes is 200 feet; however, the team chose a rope labeled 165 feet in length. Do a little math now–what do you think is going to happen? Basically, Mikey made the tail too long on his bowline. Plus, the brakeman should have used a longer rope.
Rescuers performed a system safety check, and Mikey began his descent with the patient. Prior to their reaching the ground, however, the brakeman called for a stop–he had reached the end of the rope. “Why are we stopped?” Mikey asked. “Because you’re a dope,” was the reply. Mikey and patient were still about 15 feet off the ground. (Of course, the brakeman could’ve looked at the rope ID marker and verified the length before Mikey started his descent.)
The rescuers tied another rope to the main line. They passed the knot, and Mikey and the patient finally reached the ground. Mikey owed lattes to everyone because of his “long, long tail” bowline. The lesson: Don’t waste rope!
Knot passing can be planned or unplanned. A planned knot pass occurs when you know the situation is going to require a rope longer than the one you carry. An unplanned knot pass occurs when you realize that you’re either a bad judge of distance (as in my example above) or Murphy re-stuffed the rope in your bag. (We just added a guy named Murphy to our team. Now we have an excuse for everything!)
There are many ways to pass a knot. In this article, I’ll discuss methods for passing a knot on both the main line and the belay line based upon the gear you may carry in your rigging bag. With more tools, there are more options, but in the end, you want to understand the basics of knot passing and perform the tasks using minimum gear.
1 Rope or 2?
When performing rope rescue, we in the fire service most often use a two-rope system (main line and belay line). However, if your rescue plan involves placing the load on the belay and disconnecting the main line to pass a knot, you no longer have the redundancy of a two-rope system. This isn’t a good idea when you’re faced with an unplanned event, because there may be a time when switching to the belay line is not an option. That said, you must still be able to perform the task as a stand-alone operation without relying on another system.
If working in the backcountry, you may not have a second line. In this situation, opening locked, weighted carabiners is not an option, as much of the carabiner’s strength is lost with the gate open.
Passing on the Main Line
When the brakeman is ready to pass a knot, they let the belayer know so they can lock off the belay. If using tandem prusiks, the belayer can tie a catastrophe knot behind the prusiks and help the brakeman, if needed.
At this point, you’ve already tied the two ropes together, forming the knot. Now, the brakeman must perform the following tasks to pass the knot. (Note: In the scenario described below, I use a brake rack to lower; the knot is on the main line. If your team uses another type of tool, substitute the name and appropriate lock-off technique.).
- Allow the rope to travel right up to the brake rack (Photo 2);
- Lock off/tie off with all bars (Photo 3);
- Apply a rope grab in front of the brake rack (3-wrap prusik or mechanical rope grab) (Photo 4);
- Attach the rope grab to a load-releasing hitch (LRH) (Radium, BC, Mariner’s, Hokie, etc), and attach the other end to the anchor (Photo 4);
- Push the rope grab as far forward (away from the rack) as possible, so that it’s under as much tension as possible;
- Untie the rack, and slowly lower the load until the weight is on the rope grab with the LRH;
- De-rig the brake rack, and take out the main line (Photo 5);
- Re-rig the brake rack with the knot just in front of the brake rack (Photo 6);
- Lock off/tie off with all bars;
- Tell the belayer that you’re going to lower slightly so the belay line doesn’t get stuck;
- Use the LRH to lower slowly until there’s tension on the main line (Photo 7);
- Remove the rope grab;
- Tell the belayer you’re ready to lower; and
- Lower the load.
Note: Knot passing on a belay line is simple. Basically, all you need to do is tie off the belay, and since it’s un-weighted, attach another belay system on the other side of the knot and back to the anchor. Then, tie off the new belay line, disconnect the other belay system and you’re ready to go.
The Details
To be a little more specific, when passing a knot in a system, you want someone with superhuman strength that can hold the load for you while you re-rig, regardless if it’s a lower or a raise. But, since most people don’t have superhuman strength, we have to get creative.
The secret to a successful, simple knot pass: Allow the knot to get as close to the lowering device as possible. Most often the lowering device is tied off and there’s 24—36 inches of slack between the rack and the knot. This means that whatever you use as an LRH must have that much travel prior to putting the weight on the main line. Even an LRH built with a 33′ length of 8-mm cord can be too short if too much slack is between the knot and the rack.
Remember: The control of the LRH must remain on the anchor side. If you fail to do this, the rescuer operating the line will find themselves walking toward the edge of a structure or precipice as the main line moves through the system. (Note: On a BC or a Radium LRH, the Munter hitch should be on the anchor side.)
Below are a few additional tips for knot passes.
- Do not attempt to lower the knot past the brake rack until after the rack has been re-rigged.
- Tie a knot in the end of the LRH cord. Ideally, you should capture the end of the cord and secure it back to the anchor.
- Remove any daisy chain wrap you have in the LRH cord to avoid tangles and knots as you lower the load back to the rack.
- When using a commercial Mariner’s LRH, ensure there’s enough travel to get the load back on the rack.
- When using a twin-loop runner for a Mariner’s LRH, use a minimum of a 72″ runner. If it appears to be too short, girth hitch a length of webbing to the end to extend it (Photo 8).
- Use a set-of-fours (SOF) to hold and lower the load (Photo 9).
- You can set up an independent lowering system with the end of the rope to lower the load back to the rack. This lowering device doesn’t need to be a multi-friction device because you’re only traveling a limited number of inches. Additional carabiners can be used to redirect in order to increase friction (Photo 10). In Photo 10, a second person is shown assisting in controlling the transfer of weight back to the main line.
What About a Raise?
Passing knots on a raise is a bit trickier. You’ll need an extra pulley and a length of webbing or a couple of prusiks to use as a runner to “jump” in front of the change-of-direction pulley and progress capture cam that are under a load. Try it. I’ll discuss it in a future article.
Conclusion
Passing knots is a pretty straightforward process, but one that must be taken seriously; therefore, training on knot passing, as with most rescue procedures, is imperative.
As shown in my introduction, training is where we can and should make mistakes so we can learn from them. If you find yourself without enough rope in a real rescue situation, the extra time it takes to correct the problem could mean the difference between life and death for the patient, and could jeopardize the safety of the entire rescue team. A knot pass operation should be a small bump in the road of your evolution–not a mountain.
