Grigri

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Correctly blocked Grigri

The Grigri is a semi-automatic belay device from the manufacturer Petzl for sport climbing for belaying with single ropes . It is named after the African amulets that are supposed to protect their wearers. It was launched in 1991. While the first version of the Grigris was only designed for ropes between 10 and 11 mm, the successor version Grigri 2 , released in 2011, can be used with a diameter of more than 8.9 mm.

Safe use requires expert instruction.

functionality

The device works similarly to a seat belt in a car. When the rope is pulled slowly, the rope passage is not blocked. On the other hand, a jerky cable pull in the direction of the climber activates a mechanism that completely blocks the rope. The automatic blocking only works immediately when a hand is around the brake cable. The Grigri therefore works according to the all-or-nothing principle when securing a climber. A controlled braking of the rope passage in the case of a lead fall in the sense of a device-dynamic belay is not possible with the Grigri.

In order to release the locking mechanism again (for example to be able to lower a climber), the belayer must pull the lever attached to the Grigri towards him. (In the adjacent illustrations, the lever is hidden on the side of the device facing away from the observer.) In order to suppress the blocking mechanism for quick rope payout, downward pressure must be exerted on the lever base. In both states the device does not brake the passing rope. To reactivate the braking mechanism, the belayer must release the lever or take the pressure off the lever base.

advantages

  • In the event of a fall, the device automatically blocks the rope without the person securing it having to actively stop. This has the advantage that the device can still hold a fall if the belayer does not have his hands on the rope (e.g. because he hits the wall while belaying or is unconscious from falling rocks).
  • The belayer can hold a person hanging constantly in the rope without any effort.
  • The rope does n't tangle .
  • The device is very safe when used correctly.

disadvantage

  • The device is dangerous if the user is insufficiently trained. Accidents due to incorrect use therefore occur again and again.
  • The device always blocks completely in the event of a fall. Controlled braking is not possible via the Grigri itself. This means that dynamic backup is restricted.
  • If the rope diameter is too small (less than 9.8 mm for the Grigri 1), the device no longer blocks completely, especially if the rope is still new.
  • The device only locks completely in the event of a jolt (like a car seat belt ). If the device does not jerk (because of the particular course of the rope, friction, climber 'sits' in the rope) the device may not block and the rope slips through.
  • The device is relatively heavy compared to the tuber and figure figure eight and only allows certain diameters of a single rope . It is therefore not possible to use two half or twin ropes, and abseiling is only possible on a single rope. That is why their use is often limited to climbing gardens and climbing halls.

service

Application error

  • The lever for releasing the blocking mechanism is actuated without additional protection with the brake hand. This is a mistake both when lowering and when paying out rope quickly.
  • The grigri is held in the hand when belaying or paying out rope. This prevents the Grigri from rotating freely and the locking mechanism is disabled.
  • Too fast lowering of the belayer caused by gross motor skills. The speed can be determined by opening the Grigri carefully.
  • In the event of a surprising fall due to the above error, the hand reflexively pulls the lever to release the blockage even more, which accelerates the fall even more. The GriGri + tries to solve this problem with the anti-panic lever, in which the device locks when the lever is pulled through completely.
  • The braking hand leaves the rope when the rope is blocked. This is a mistake often made by more experienced climbers who secure the rope without a hand. They trust that the blocking mechanism will hold without any action on their part. But this is not always the case. If the rope is relieved (by briefly releasing the belayed) and then not suddenly but gradually increasing the load, it can happen that the locking mechanism does not work completely.
  • The rope is incorrectly inserted into the device. The blocking mechanism does not work in this state.

Since improper use occurs due to insufficient training and repeatedly led to accidents, belaying with the device, which is extremely safe in and of itself (together with other semi-automatic machines), was even prohibited in individual climbing halls. A large study on indoor climbing shows that such bans are not based on objectively collected data, which examined the question of the influence of the belay device on the probability of accidents on the basis of standardized observations on behavioral errors. The widespread figure eight with 40% errors performed clearly worse than the Grigri with 28.6%. The authors concluded from this that the dangers of securing griggies are significantly lower than expected and are generally overestimated. A climbing hall study published by the German Alpine Association in 2013 showed that with semi-automatic machines (including the Grigri) significantly fewer dangerous safety errors are made (less than 0.2 dangerous errors per safety procedure) than with the Tuber (more than 0.5 dangerous errors per Backup process).

Correct operation

Inserting the rope into the Grigri: the brake rope runs downwards, the rope to the climber to the right out of the device.

Despite the disadvantages mentioned above and possible application errors, with the exception of the somewhat limited dynamic backup, the Grigri can be used to back up very well if operated correctly. The following aspects must be taken into account:

  • Before climbing, a partner check is carried out to determine whether the rope has been correctly inserted into the device, for example by means of a blocking test. (An abrupt pull on the load rope should trigger the locking mechanism.)
  • The rope is released quickly when leading the climb using the gasworks method : the braking hand continuously grips the brake rope and for safe and rapid release of rope when attaching the intermediate safety devices, only the thumb of the braking hand leaves the brake rope and suppresses the blocking mechanism for as long as necessary by applying light pressure on the lever base.
  • The braking hand always remains on the brake cable.
  • If there is no danger of falling or impacting the ground, the belayer takes a step in the direction of the fall or actively bounces off the ground so that the fall is not braked too abruptly - in the sense of a body-dynamic belay - unless it is that the climber is significantly heavier than the belayer.
  • In the event of a fall, the belayer is ready and trained to prevent the body from hitting the wall with his feet.
  • When lowering the brake hand, the brake hand holds the brake cable, while the guide hand releases the blockage by carefully pulling the lever handle and assists in regulating the lowering speed.

The correct operation of the device should be learned and practiced under expert guidance.

Further development

Grigri 2

On February 1, 2011, the successor model Grigri 2 appeared on the market. It is compatible with all UIAA single ropes between 8.9 and 11 mm thick (optimized for ropes from 9.4 to 10.3 mm). The belay device has now saved 20% of its previous weight (now 170 g) and 25% of its original size. In June 2011, some of the devices that had already been sold were recalled because the brake lever could be damaged under certain circumstances and as a result the brake support of the belay device no longer works correctly. In this case, the Grigri works like a tube . Petzl then increased the strength of the brake lever on newly manufactured devices.

Grigri +

At the OutDoor 2016 in Friedrichshafen, Petzl presented the Grigri +, which has been available since April 2017. In addition to minor adjustments, the support of a larger range of rope diameters (optimized for ropes from 8.9 to 10.5 mm), the ability to regulate the sensitivity of the blocking mechanism and panic protection of the release lever are among the greatest innovations.

Grigri 3

The current model "Grigri 3" has been on the market since April 1, 2019. Officially it is only called GRIGRI by the manufacturer. The new model replaces the Grigri 2 and covers an even larger range of rope diameters (8.5 mm to 11 mm).

literature

  • Britschgi, Walter (2004): New Findings from Security Research. Safe indoor climbing. In: Die Alpen 3/2004, pp. 22–24.
  • Britschgi, Walter (2004): Safely secure partners 1. Elementary safety errors and the 3-leg logic (PDF; 200 kB) In: bergundstieg 2/2004, pp. 64–69.
  • Köstermeyer, Guido (2001): Belay devices in comparison. In: Köstermeyer, Guido / Neumann, Peter / Schädle-Schardt, Walter: Go climb a rock! Sport climbing- Current aspects for teaching, practicing and experiencing. Hamburg, Czwalina, ISBN 3-88020-379-2 .

Web links

Commons : Gri-gri  - collection of images, videos and audio files
Wikibooks: Belay devices and descenders at Wikibooks  - learning and teaching materials

Individual evidence

  1. ↑ Das Grigri: An idea that changed the sport of climbing. In: petzl.com. July 22, 2015, accessed November 10, 2015 .
  2. ↑ Haslwanter Thomas (2001): “Firstly, things turn out differently ...” Indoor climbing accident - an analysis. (PDF; 444 kB) Accessed January 25, 2008.
  3. ↑ Petzl: GRIGRI Experience Accessed January 10, 2014.
  4. ^ Pauli Trenkwalder, Martin Schwiersch, Jan Mersch, Dieter Stopper: Hall climbing. Part 2. Factors influencing behavior failure . In: mountaineering . No. 2 , 2005, p. 52–57 ( PDF [accessed May 18, 2016]).
  5. ↑ Felix Funk, Martin Schwiersch, Florian Hellberg: Climbing hall study 2012: Looked at your fingers . In: Panorama . No. 2 , 2013, p. 66–69 ( PDF [accessed December 11, 2019]).
  6. ^ Britschgi, Walter (2004): Safely secure partners (2). Risk management and safety training (PDF; 424 kB) In: Bergundstieg 3/2004, p. 46, accessed January 25, 2008.
  7. ↑ Semmel, Chris / Stopper, Dieter (2003): Safely secure In: DAV Panorama 4/2003 p. 60, accessed: January 25, 2006.
  8. ↑ GRIGRI® 2. Petzl, accessed on November 10, 2015 .
  9. ↑ Recall: backup device Grigri 2 Petzl ( Memento of 9 August 2011 at the Internet Archive ) on klettern.de ; Retrieved July 18, 2011.
  10. ↑ Petzl presents the new GRIGRI +. In: Bergleben. July 18, 2016, accessed July 22, 2016 .
  11. ↑ GRIGRI® - Belay devices and descenders | Petzl Austria. Retrieved June 17, 2020 .