Grigri Lock-offs
A little extra security.
→ Two iconic belay devices have dominated the last 30 years of rock climbing. Which came first, the Black Diamond ATC or the Petzl Grigri?
For folks unfamiliar with the world of rock climbing, the Petzl Grigri dominates the assistive braking device (ABD) segment for belay devices to the point where the term has almost become synonymous with ABDs. We have reached a tipping point where a significant portion of new climbers are first learning how to belay on ABDs or quickly adopt them. These modern Grigri-using climbers default to single-strand rappelling rather than the double strand rappels common with ATC and other similar tube-style devices.
The Grigri’s popularity after almost 40 years highlights its iconic reliability for both belaying and rappelling. High reliability has led to many rope users from many disciplines resting on a loaded device and removing their hand without otherwise securing the brake strand. This goes against Petzl’s recommendation, but it (usually) works.
In this article I focus on a few ways to secure a rappel when stationary – two manufacturer approved & two off-label variations I have found useful in my own personal tree & rock climbing.
The Problem(s)
Securing the brake strand before removing the brake hand is a choice, but not a universal practice in the world of rock climbing. Some potential issues with the Grigri which might influence this choice:
Petzl technical information warns removing the brake hand & recommends two different methods of securing the brake strand. In a professionally managed risk environment (work or institutional setting), acting against Petzl’s recommendations increases liability exposure for the institution or individual. Good policies, procedures, training etc. may mitigate this exposure enough for
The Grigri is designed for belaying, and must balance a quick and reliable lock-up with ease of moving the rope through the device. A spring holds the locking cam in the open position when the device is unweighted. A rappelling climber may accidentally unweight the Grigri, unlocking the device.
If the device is unlocked the locking mechanism can be defeated.
The climber may panic-grab the anchor/climber side of the line, preventing the device from “feeling” enough of a load to fully lock.
An object can hold open the exposed cam delaying or preventing it from locking. Notice how Petzl’s dedicated descent devices (the I’D and Rig) have cams which are shielded by the sideplates of the device.
If the device is locked, it can be accidentally unlocked if the handle opens and becomes pulled. For example, I have personally had a pack catch on the lever of a descender and the weight of the heavy pack released the device.
The device may slip or drop the climber due to other factors not mentioned above.
Solutions
This article discusses four (of many) potential approaches to securing the brake strand:
Catastrophe Knot - Stable & Closed (Overhand on a Bight)
Carabiner Spine Tie-off
Catastrophe Knot - Overhand Slip Knot
Half-hitch Tie-off
Only the first two are recommended by Petzl. The other two are presented here for interested, experienced rope users.
A Word of Caution
The solutions described here are strictly intended for use on rappel to prevent an uncontrolled descent - not catch a fall, as might be found with a conventional rock climbing belay or rope soloing. One consideration is that the Grigri-like devices will usually slip under high loads, which limits the peak load to the device. Certain methods of securing the brake strand prevent slippage and can cause the device to fail by overloading.
For example, the Madrock’s instructions for the Lifeguard & Safeguard devices (popular with saddle/tree-climbing hunters) specifically warn against tying a knot in the braking side of the rope.
Manufacturer Recommended Solutions
Catastrophe Knot - Stable & Closed
Petzl recommends tying a knot below the device which is stable and closed, such as the overhand on a bight.
The overhand on a bight is a common choice because:
relatively economical with rope use compared to say the figure 8 on a bight.
stable
simple to tie & easily identified
well known to climbers - so much so that catastrophe knot or cat knot is synonymous with an overhand on a bight.
In the event of an uncontrolled descent, the climber can only descend as far as that knot. This limits the risks the climber is exposed to, but they could still potentially injure themselves or trap a limb.
A catastrophe knot as a backup solution has the benefit of permitting minor adjustments up and down the rope without re-establishing the backup. Of course, straying too far from the initial position will either permit a dangerously long uncontrolled descent or jam the knot against the device, which can be difficult to untie.
Carabiner Spine Tie-off
Another method recommended by Petzl is to tie the brake strand off to the spine of the carabiner using a mule knot (aka overhand slip knot). The knot is further secured with a carabiner.
Pros:
uses little rope (less than overhand on a bight)
zero-distance uncontrolled descent
easy to untie & resume descent
Cons:
Does not permit easy positional adjustment - a tradeoff of a zero-distance backup
Off-Label Solutions
These solutions are not approved by Petzl, but may be familiar to tree climbers or cavers. I feel comfortable sharing them here, as they are providing extra security to what is already a relatively secure situation – a climber fully weighting a stopped Grigri on rappel. I have used the two techniques for many years, but they are only presented here as food-for-thought. Climbers who use these should do so at their own risk.
Cat Knot - Slip Knot
Instead of using the overhand on a bight as a catastrophe knot, tree climbers are comfortable using a slip-knot (left), as this is easily untied . It can be further secured by forming a half-hitch in the slippery end and placing that over the bight (right), and/or a carabiner through the bight.
Pros:
Permits positional adjustment as with the traditional cat knot.
Even more economical with rope
Easy to tie, and secure
Directional - easy to untie & resume descent
Well known to tree climbers
Cons:
Typically is not as secure as an overhand on a bight
Directional - possible to tie upside down
Can be mistaken for a butterfly when secured with a half-hitch (see this post on the False Butterfly)
Half-hitch Tie-off
This lockoff is very natural to cavers used to rappelling with a bobbin descender. A bight of rope is passed through the carabiner, given a twist (to form a half-hitch), then placed over + around the device. The working end of the brake strand is pinned against the device and carabiner by the standing portion between the tail and the device.
Pros:
Very quick and secure when in a vertical position
Easy to remove & resume descent
Cons:
Less stable if device/rope is slacked repeatedly/cycled
Stability depends a bit on rope diameter & specific Grigri model.
Does not permit easy positional adjustment
Other Choices
There are a range of other choices which might be acceptable in professional or recreational settings. This article highlighted four solutions, but is not a comprehensive look at the grigri as part of a greater climbing/rappelling system.
Final Thoughts
A non-comprehensive list of other considerations:
Hopefully your partners are watching your back – will they be able to recognize when you have made a mistake when establishing a backup? Do they really know what you’re up to?
What backup methods will YOUR climbing partners recognize and competently interact with if you are not conscious?
What are common situations in YOUR climbing where your preferred backup method might be inappropriate? Will it manage risk appropriately? What are good alternatives in these situations?
Many of these techniques work with Grigri-like devices from other companies, but what do these manufacturers say about securing their device on a rappel?
Why?
Given the potential problems rappelling with a Grigri, maybe a dedicated descent device such as a Petzl Rig or Edelrid Megawatt would be a better choice. In many ways this article highlights skills for :
grigri rappelling rock climbers
rock climbers turned tree climbers looking to share equipment across disciplines
tree climbers from 2009, living in a world before the Petzl Rig and (later) modern SRS became accessible.
rope users with needs being met by other off-label use of equipment (e.g. rappelling on a Petzl Grillion).
As a recreational climber, I have the freedom to thoughtfully apply off-label solutions, which I have carefully tested in my particular application. Please don’t get hurt based on some internet article. Make good choices – maybe that is using a backup if you currently do not.
Further Reading
From Petzl.com:
(Gen 1) Grigri Technical Notice (archive.org – 2005)
(Gen 3) Grigri Technical Notice (2025)
Hands Free Position with the Grigri (2019) (archive.org - technically archived after Gen 3 release, but same page linked to by Gen 2, and Grigri+ in 2017)
Madrock Safeguard Instructions – warns against catastrophe knot use
False Butterfly – discusses in more detail the method of securing an overhand slip knot and potential pitfalls.
→ Grigri was released in Summer of 1991 (Mountain Magazine 142, 1991 Nov/Dec), and the Black Diamond ATC in 1992 (BD catalog).