Should a safety knot be a slip knot?

Moss had mentioned a TCC safety article so I was browsing through them and was reading this one. It raises a question about safety knots. It seems to me that the situation described in the article could not have happened if the knot had been tied correctly -- so the knot in question was already a safety hazard even before the kid stuck his foot in the loop. Apparently it had been tied upside down. Should newbies be taught to use slip knots for safeties? I myself began using simple overhand knots as a safety knot because I know it will stay there and it really isn't going to take much time to untie anyway.

If your overhand safety knot ever does what it is designed to do, that is, arrest a fall, you'll have a very difficult time getting the knot out of the rope. You might even require rescue, because you may not be able to undo it if you fell hard enough on it. Additionally, to tie an overhand in your rope on a high climb would mean pulling 50+ feet of rope, or more, through each knot. And, come to think of it, would mean passing knots through the loops that you would make when tying subsequent safetys on the way up.
The issue here is not the slip safety knot. The issue is education and supervision

Oh no, I meant an overhand knot on a bight. The good thing is that it will stay there. It can't be tied improperly or accidentally untied by a rope snag.

If your overhand safety knot ever does what it is designed to do, that is, arrest a fall, you'll have a very difficult time getting the knot out of the rope. You might even require rescue, because you may not be able to undo it if you fell hard enough on it. Additionally, to tie an overhand in your rope on a high climb would mean pulling 50+ feet of rope, or more, through each knot. And, come to think of it, would mean passing knots through the loops that you would make when tying subsequent safetys on the way up.
The issue here is not the slip safety knot. The issue is education and supervision

Overhand on a bight can't be taken out from the ground by a facilitator. That's the primary use of a slip knot/safety knot, to prevent uncontrolled descent in a facilitated climb situation. The facilitator needs to be able to remove them remotely or they're going to be spending alot of time climbing up and rescuing folks. The knots should be placed close enough so that the climber isn't going to be going very fast when they hit the knot, but it will stop their downward progress.

I agree with Baker, it's the responsibility of the climb facilitator to make sure slip knots are tied correctly. I think Joe posted that report on the TCC forum as a heads up for facilitators, don't let climbers make the bight too large on the slip knot.I don't think there is any intrinsic safety issue with the knot, it's an excellent safety tool/technique.
-moss

moss wrote:

I agree with Baker, it's the responsibility of the climb facilitator to make sure slip knots are tied correctly. I think Joe posted that report on the TCC forum as a heads up for facilitators, don't let climbers make the bight too large on the slip knot.I don't think there is any intrinsic safety issue with the knot, it's an excellent safety tool/technique.

Well, maybe I'm misunderstanding what Joe wrote. I thought he was saying the loop tightened on the kid's leg - thus the knot wasn't tied correctly anyway.

"He still had both hands on the Blake's hitch and as he pulled down, his weight on the safety knot was causing it to cinch itself even tighter, creating a tourniquet around his leg. He was yelling from the pain..."

Davej wrote:

Well, maybe I'm misunderstanding what Joe wrote. I thought he was saying the loop tightened on the kid's leg - thus the knot wasn't tied correctly anyway.

"He still had both hands on the Blake's hitch and as he pulled down, his weight on the safety knot was causing it to cinch itself even tighter, creating a tourniquet around his leg. He was yelling from the pain..."

Definitely, I'm saying that it's the facilitator's responsibility to observe when a climber makes the bight too large and instruct the climber to reduce the size of the bight on the slip knot. Facilitators can't put climbers on rope and go off and chat with people on the ground, they have to be constantly watching the climbers.
-moss

Interesting scenario... it seems like you could easily unweight the jam up with a simple yo yo lanyard clipped onto the line... i might have to make a moss style video to explain that but it's the same concept as a mechanical advantage pick off strap.

About the slipknot... I was taught that the overhand knot on a bite can be safer because with a stiff rope the slip knot can easily come out once enough rope weight is accumulated... if you have never climbed with a wet frozen BRW or similar rope i can tell you it's HEAVY... i started climbing in winter and the overhand on a bite was a no brainer. Now with a softer more knotable rope on a warm dry day, sure i would trust a slip knot to stay tied... would i trust someone to tie it right side up 100% of the time? no

I imagine it's difficult to visually find one tied backwards with a few people 50feet in the air... and there is no way to monitor how tight they are tied.

I realize there is an impeccable safety record in recreational tree climbing, but i feel belaying the tail is a safer alternative to the slip knot method. I can belay two people through the small eye of my figure 8 and tie a knot behind the small eye to lock off a climber. This puts the knot on the ground where not only can i see the knot up close, i tie it myself. Another way to belay the tails would be to use spring loaded rope grabs on a rigging plate secured to the trunk... this way the climbers could be given slack as needed. Thoughts?

Not all things are predictable, i have found that one of the joys of climbing is using problems solving and logic to remove the danger of unpredictable events... it's a sense of freedom.

adam

A note on belaying the tail: Whenever beginners or first-time climbers want to descend, they follow the clearly stated climb protocol (pre-climb orientation/instruction) and ask for permission before they start going down. The facilitator pulls out all the safety/slip knots from the ground and belays the climber until their feet are on the ground. The purpose of the slip knots in the climber's tail is to protect them from accidental descent while they are climbing or to stop them if they attempt to descend without permission.

The safety/slip knot is an excellent tool, it allows a facilitator to manage multiple climbers at the same time from the ground. The reason that the technique is so widely used by rec climbing facilitators is because it is very effective for running group climbs. I wouldn't use it if it hadn't proved itself to me again and again over many group climbs.

It's worth remembering that the safety knot is just one part of the safety picture for facilitated climbs. No one technique or procedure is more important than the facilitator maintaining focus from the beginning to the end of the climb.
-moss

ReginaARC wrote:

I imagine it's difficult to visually find one tied backwards with a few people 50feet in the air... and there is no way to monitor how tight they are tied.

Edit: I removed my foolish statement about an upside down safety, indeed it will fall out when hit by a hitch going down.

It's funny though, I just don't see it happening during climbs (climbers putting them wrong side up). They often do it on the first one or two at the beginning of the climb, after they're corrected they seem to do them. I guess people are smarter than you might think.


It's not an issue if the slip knot is tied too loose. If it's so loose that it falls out you instruct the climber to tie another one. As long as the slip knot is tied and it is there, it will stop the climber. Remember, they are not flying 60 feet and hitting the knot, they would theoretically be sliding no more than ten feet and hitting the knot, it will stop them as long as there is a formed slip knot in place.
-moss

It says "his weight on the safety knot was causing it to cinch itself even tighter, creating a tourniquet around his leg."

This implies that the slip knot was tied upside down in my opinion. Had it been tied right side up the slip knot would cinch down upon the loop of rope and not his leg.

The slip knot is a directional knot as opposed to a bidirectional knot like the overhand on a bite. Moss, I think you thought backwards meant like the inversion (right over left, left over right) which i agree makes no difference.... but here I'm talking about reversing the ends of the knot.

Once again, i doubt you could see from 50 feet if a slip knots direction is correct... if it's up side down it would most definitely do nothing to stop an uncontrolled descent.... that is of course unless it has an object like a leg stuck in it.

We're talking apples and oranges here. For your personal climbing, use whatever safety knot (if you use one) makes you safe and happy. For facilitated climbs, you need a knot that can be taken out from the ground. Unless you want to be doing constant aerial rescues untying climber's overhand on a bight or other types of safety knots for them.

A rec climbing instructor sent me a note to mention that his protocol is to always tie the safety knots for first-time climbers especially children. I'm 100% in agreement.

The incident mentioned was facilitator error, they made the bight on the knot too large.

If anyone can come up with a safety knot (besides a slip knot) that can be placed on the tail of the rope and can be removed from the ground by the facilitator I'm all ears. Otherwise I'm 100% satisfied with the current strategy.
-moss

moss wrote:

We're talking apples and oranges here. For your personal climbing, use whatever safety knot (if you use one) makes you safe and happy. For facilitated climbs, you need a knot that can be taken out from the ground.

Ok, I'm just making conversation here. My issue is just that facilitated climbs teach the gospel of the slip knot as being the "right and proper" knot to use for safety -- but then these kids go home. Do they climb at home?

Davej wrote:

Ok, I'm just making conversation here. My issue is just that facilitated climbs teach the gospel of the slip knot as being the "right and proper" knot to use for safety -- but then these kids go home. Do they climb at home?

Nope, they'd need arb rope, harness, throwing gear, ability to tie the knots etc. None of that is taught at a facilitated climb. The facilitator sets the ropes, ties the knots and takes care of each climber during the climb.
-moss