Self-belay: introduction


Important Important
  • Solo climbing is not recommended: climbing with a partner remains the best solution
  • Climbing is inherently dangerous, you are responsible for your actions and decisions
  • Self-belayed solo climbing must only be undertaken by experts
  • This case deals with climbing with a fixed belay rope, without loading the rope (except to rest). Ascending on the rope (caving, big wall, crevasse rescue, alpinism, etc.) is not addressed here.
  • If an accident results in unconsciousness (fall, rockfall), rescue will be difficult. Wearing a helmet is strongly advised. DO NOT CLIMB without one. Do not climb solo without informing a person of your destination and when you will return
  • No solution is universal; you must be able to adapt our proposed technical solutions to your chosen terrain
  • A good understanding of the solutions proposed in this supplementary information requires that you have consulted, understood and assimilated the Instructions for Use for all devices concerned
  • The proposed systems are complex; any modification can stop them from functioning properly
  • Only the techniques shown in the diagrams that are not crossed out and/or do not display a skull and crossbones symbol are authorized

Failure to heed any of these warnings may result in severe injury or death.

 

1. Introduction

In climbing or mountaineering, the rope team offers the highest level of safety. Nevertheless, fixed-rope solo climbing is an option that many climbers have taken, experimenting with a variety of technical solutions.

Petzl has not developed a device for this activity, but certain ascenders may be used for it by experts.

The solutions proposed in this document take into account known practices and accident records, with the objective of proposing to the solo climber a system of belaying that takes into account at least these qualities:

  • Effective stopping (belay)
  • Easy sliding along the rope while climbing
  • Ease of use
  • Redundancy of the belay

Petzl does not recommend using only one ascender for self-belaying.

Using a single ascender is technically feasible, however, accidents have been reported despite user expertise. The risks are real in the field, so Petzl recommends using a system with a secondary belay.

In effect:

  • You are moving alone over dangerous terrain
  • Mishandling is always possible
  • Ascenders are not specifically designed for self-belayed climbing
  • It must be understood that all systems are flawed, because this means there is a risk, however minor.

Examples of possible malfunctionssee detail

Important Examples of possible malfunctions during self-belayed solo climbing with a fixed rope.
The probability of experiencing these malfunctions is very low, but not negligible, and it only takes once...
ASCENSION: There is the possibility of accidental opening of the cam due to rubbing against the rock, or that the device will not jam due to an external object interfering with the cam (sling, shoelace, twig, etc.). Risk of improper attachment of the device. MINI TRAXION: The jamming function can remain deactivated without the climber's knowledge and visual verification isn't always easy. There is the possibility that the device will not jam due to an external object interfering with the cam (sling, shoelace, twig, etc.).
BASIC: There is the possibility of accidental opening of the cam due to rubbing against the rock, or that the device will not jam due to an external object interfering with the cam (sling, shoelace, twig, etc.). Risk of improper attachment of the device. New BASIC: The new design of the upper attachment hole makes it unsuitable for use in self­belaying: there is a risk of interference between the carabiner and the safety catch. This device is not suitable for self-belaying.
MICROCENDER: There is the possibility that the device will not jam due to an external object interfering with the cam (sling, shoelace, twig, etc.), or if the rope is dirty, muddy or frozen. Handling is more difficult. SHUNT: Greater danger on sloping terrain where pressure against the device can impede jamming. The device will not jam if the user grabs the device during a fall.
MICRO TRAXION: There is the possibility that the device will not jam due to an external object interfering with the cam (sling, shoelace, twig, etc.). TIBLOC: To work properly, the TIBLOC's teeth must be manually pressed against the rope, which is impossible to do while climbing, and dangerous at the moment a fall occurs. The TIBLOC is not suitable for self-belaying.

Introduction to the principle of redundancy of the belaysee detail

Introduction to the principle of redundancy of the belay

Considering the possible malfunction of a single belay system, the usage of a secondary system is strongly recommended.
The secondary system is "redundant", it is installed as a backup to the first system.
The redundancy of the belay should not be understood as a supplementary constraint, but as a necessary precaution.

Major characteristics of a secondary belay system:

  • No interference with the working of the primary system.
    Example: contact between the two devices while climbing must be impossible.
  • Continuous belay.
    Example: a lanyard for occasionally resting on a point of protection is not a continuous belay system.

Recommended characteristics:

  • The primary and secondary systems should be different, to limit the risk of repeating the same error.
    Example: if the primary system is a MINI TRAXION, the secondary system should be another device.
  • No increase in complexity of installation or functionality, ease of use at least equal to primary system.
    Example: if the primary system slides along the rope without the need for manual intervention, the secondary system cannot require manually pulling slack through the device.

2. Expert only Installation on two ropes with two ascenders

Installation on two ropes with two ascenders

Primary system: one ascender on the belay rope.
Secondary system: one ascender on the backup rope.

Advantages:

  • Principle of redundancy is followed for the anchors as well.
  • Comfortable, allows wearing only a sit harness without shoulder.
  • Facilitates changing between "ascent" and "descent" modes.
  • The system slides along the rope, without pulling.

Disadvantages:

  • Rope installation is more complex.

Risks in case of primary ascender malfunction:

  • Fall height of twice the length of the secondary ascender's attachment lanyard.
 

Installation on the harness with two ascenders:see detail

The primary ascender is connected to the harness belay loop with an OK carabiner.

A MICROCENDER is positioned on the other rope as a backup. It is connected to the harness tie-in points with a quick link (PRESTO or GO), a 17 cm EXPRESS sling and an OK TRIACT LOCK carabiner.
After installation, verify that each ascender slides correctly on the rope in the up direction, and jams instantly in the down direction.
Before climbing, verify that all connectors are locked.

 

Gear necessary for the self-belay system:

  • two EN 892 dynamic single ropes or two EN 1891 semi-static ropes of 10 mm minimum diameter
  • a primary ascender (ASCENSION, MICRO TRAXION, BASIC, MINI TRAXION), and its OK connector,
  • a secondary ascender: MICROCENDER and its OK TRIACT-LOCK connector
  • an EXPRESS 17 cm sling
  • A PRESTO or GO quick link, tightened with a wrench

Detail of installation on two ropes with two ascenderssee detail


 

Installing the secondary ascender: MICROCENDER only!

If primary ascender fails, there is a possibility of a factor 2 fall onto the backup ascender (twice the length of the extension). This type of fall is prohibited with a frame-loaded ascender, used without an energy absorber (ASCENSION, BASIC, MINI TRAXION, etc.), because the rope's sheath will be damaged or torn by the cam's teeth. Petzl therefore recommends using a cam-loaded ascender: the MICROCENDER.

Fall tests (height = twice the length of the extension), close to the knot, 80 kg dummy.

Emergency ascender Extension Impact force Effect on the rope
MICROCENDER GO + EXPRESS 17 cm + OK 4.8 kN  
ASCENSION GO + absorber NITRO + OK 4 kN  
ASCENSION GO + EXPRESS 17 cm + OK 4.7 kN 185 cm of sheath torn

Notes:

  • Always carry a descender (GRIGRI) and a footloop/ascender combo (TIBLOC + ANNEAU) to ascend the rope in case of failure to complete the climb
  • The two ascenders must not be connected to the same point on the harness: they can collide and be damaged during a fall
  • Roofs and traverses complicate the system: they require numerous directional points and additional precautions. Do another risk analysis for these particular cases

3. Expert only Installation on one rope with two ascenders

Installation on one rope with two ascenders

Primary system: one ascender on the belay rope.
Secondary system: a second ascender on the same rope.

Advantages:

  • Allows the use of longer ropes
  • Reduces weight for long approaches
  • The system slides along the rope, without pulling.

Disadvantages:

  • Requires the use of shoulder straps to properly tow the secondary
  • The principle of redundancy is not followed with respect to the belay rope. WARNING, repeated rubbing against the rock can quickly cut your only rope.

Risks in case of primary ascender malfunction:
The second ascender stops the fall without interfering with the primary system.

 

Installation on the harness and TORSE with two ascenderssee detail

The primary ascender is connected to the harness belay loop with an OK carabiner.
The secondary ascender is connected to the harness attachment points with a quick link (PRESTO or GO), an extension (17 cm EXPRESS sling + STRINGs) and an OK TRIACT-LOCK carabiner. It will be held up and pulled by the shoulder strap (TORSE C26), connected to the eye of the quickdraw.

After installation, verify that each ascender slides correctly on the rope in the up direction, and jams instantly in the down direction.
Before climbing, verify that all connectors are locked.

 

Gear necessary for the self-belay system:

  • one EN 892 dynamic single rope or EN 1891 semi-static rope of 10 mm minimum diameter
  • a primary ascender (ASCENSION, BASIC, MICRO TRAXION) and its OK connector
  • a different secondary ascender (MICROCENDER, BASIC, MICRO TRAXION, MINI TRAXION) and its OK connector
  • TORSE shoulder straps
  • an EXPRESS 17 cm sling
  • A PRESTO or GO quick link, tightened with a wrench

WARNING, repeated rubbing against the rock can quickly cut your only rope.

Detail of installation on one rope with two ascenderssee detail


 

Notes :

  • The quickdraw helps avoid collisions between the devices, but should not interfere with comfort: adjust its length so the strap does not pull on the neck during a rest or fall.
  • The two ascenders must not be connected to the same point on the harness: they can collide and be damaged during a fall
  • Respect the recommended ascender position: BASIC above and ASCENSION below The reverse position turns out to be tricky when changing systems from ascending to descending.
  • Always carry a descender (GRIGRI) and a footloop/ascender combo (TIBLOC + ANNEAU) to ascend the rope in case of failure to complete the climb
  • Roofs and traverses complicate the system: they require numerous directional points and additional precautions. Do another risk analysis for these particular cases
 

4. Precautions, risks and alternative techniques

Precautions and introduction to risk analysis

Attaching the ASCENSION and BASIC for self-belaying:see detail

The device must be installed correctly on the rope, connected by the upper attachment hole, taking care to capture the rope in the carabiner.

Notes:

In these situations with fall factor less than one, the ascender's teeth do not damage the rope. Despite their aggressive appearance, the teeth on the BASIC or ASCENSION are not harmful to the rope in normal use.

The spring pushes the cam against the rope and causes it to engage the rope without sliding (and therefore without tearing), especially if the teeth are new and pointy.

Use of the MINI TRAXION pulleysee detail

Warning!

Petzl has studied the current usage of the MINI TRAXION as a self-belay device on a fixed rope. Serious accidents and many handling errors have been reported.

The risk of using the device with the cam held open is significant, as well as the possibility of accidental opening of the cam when climbing.

Consequently, the MINI TRAXION must be paired with a different ascender: ASCENSION, BASIC, MICROCENDER...
Petzl does not recommend using a system consisting of only two MINI TRAXION for self-belayed solo climbing with a fixed rope.


Attention: in this photo, the MINI TRAXION's ascender function is deactivated.
 

Non exhaustive risk analysissee detail

The risks vary with the situation: do your own analysis!

Introduction to the installation risks:

  • Access from above presents a risk of falling before the rope is installed, be vigilant when approaching the anchor
  • Beware of rockfall while accessing the route from above, and when the rope is moving
  • Anchor or rope failure: adapt your installation to the site, choose a solid anchor on two triangulated points, avoiding rub points against edges or protrusions. A rope protector (PROTEC C45) may be required
  • Risk of ground fall: in the first few meters of the climb, even with a properly installed system, you can hit the ground in case of a fall, due to the elasticity of the rope. The static elongation of a rope is around 10 %. If your route is 50 m, there is a risk of ground fall in the first 5 meters of the climb, even from simply resting on the rope

Introduction to handling risks:

  • Sliding of the device: improper attachment, opening of the cam during use (rubbing, interference from foreign objects)
  • Device loss: when changing systems from ascent to descent, putting the descender on the weighted rope is tricky
  • Rope loss: If you are tied off to an anchor on a slab route, do not detach yourself completely from the rope: a slight pendulum can move the rope out of your reach
  • Slack rope: if the rope is not sufficiently weighted, the system cannot slide fast enough to keep pace with the climb and loops of slack are created between you and the anchor. The potential fall length will increase
  • Passing the belay and falling = factor 2. Always stay below your anchor point, making sure your setup allows for this during access and return

Analysis of solutions observed in the field, respecting the principle of redundancy of the belay

Introductionsee detail

Solutions following the principle of redundancy:

Diverse solutions have been proposed by climbers practicing self-belaying. Redundancy in belay systems is generally arrived at by consensus of regular practitioners, by making knots in the rope, or by using a second ascender to "double-up" the primary ascender.
The user is responsible for his or her choice among the many possible belay systems. To guide this choice, it is necessary to envision not only standard falls, but also falls made worse by a malfunction of the primary belay system.

 

Expert only Solution with one ascender and one rope, plus knotssee detail

Primary system: an ascender on the rope.
Secondary system: knots tied in the rope while climbing, below the ascender.

The knots are left in the rope below the climber.

Advantages:

  • Simplicity of the system and its installation.
  • Low equipment cost.

Disadvantages:

  • The principle of redundancy is not followed with respect to the belay rope. WARNING, repeated rubbing against the rock can quickly cut your only rope.
  • Need to regularly have both hands free to make knots: impossible if the climb is overhung, so there is a risk of climbing rather far above the last knot in certain sections.
  • In case topping out is necessary to exit the route, retrieving a rope with many knots in it could be complicated or even dangerous. Risks in case of primary ascender malfunction: Significant potential fall height. The user will fall to the first knot in the rope. The ascender is not designed to sustain the impact on the knot.

Risks in case of primary ascender malfunction:

  • Significant potential fall height.
  • The user will fall to the first knot in the rope. The ascender is not designed to sustain the impact on the knot.
 

Results of a test series done by Petzl:

Test scenario: simulation of primary device malfunction. Cam intentionally deactivated for the test Fall onto the knot with an 80 kg dummy attached to the ascender. The start of the fall is fixed at 2 m from the anchor, so an "average" position: closer to the anchor, the fall factor will be higher and the impact more severe.

Two fall heights were envisioned:

  • "Standard" fall height = 2 m fall above the knot (factor 0.5).
  • Fall height of a climber required to climb through a sustained section = 5 m fall above the knot (factor 0.71).

The same falls were repeated on 11 mm diameter dynamic, semi-static, and static ropes.

During these tests, the knot stopped the fall each time.
However, stopping the fall is not a "sufficient" result to validate these tests, because the climber is then faced with other problems.

 
The impact force is high: always greater than 4 kN, and up to more than 8 kN for falls on static and semi-static ropes.
The rope is sometimes damaged (sheath torn, several core strands broken): when the cam re-engages during the fall, or when impacting the knot.
The device is damaged by the impact in most cases:
  • MINI TRAXION: bent side plates and axle. The device is no longer usable, the climber must use another ascender, or descender, to escape.
  • MICRO TRAXION: bent moving side plate and axle. The device might be usable for the escape, but must be retired immediately afterward.
  • ASCENSION: bent frame in the most severe cases. The device might be usable for the escape, but must be retired immediately afterward. The knot jams between the carabiner and the body of the device. In case of a poor attachment, the rope will come free.

Petzl does not recommend this solution as its effectiveness is uncertain.

Expert only Solution with one ascender and two ropessee detail

This solution is described here because it is often presented by users. It has poor ergonomics and a high risk of error.

Primary system: one ascender on the primary rope.
Secondary system: pre-tied knots spaced regularly on the second rope for clipping with a lanyard.

Advantages:

  • Simplicity of the system and its installation.
  • Low equipment cost.

Disadvantages:

  • The second rope can not be considered a belay system unless the climber is continuously connected to it. A Y-lanyard must be used and the user must be clipped to the next knot before unclipping from the last knot.
  • Fair ease of use: the climber lifts the secondary rope with each move upwards and supports its weight.
  • In case topping out is necessary to exit the route, retrieving a rope with many knots in it could be complicated or even dangerous.

Risks in case of primary ascender malfunction:

  • Significant potential fall height.
  • With an I-lanyard, the secondary system belay is not continuous.
  • Close to the belay anchor, there is a risk of a fall factor 1: beware if the rope is semi-static. With a static lanyard, the fall factor close to the belay anchor can be greater than 1. (A dynamic rope lanyard is preferred.)