Grigri (climbing)

The Grigri is a semi- automatic belay device manufacturer Petzl for sport climbing to back with single ropes. It is named after a protective amulet, the Tuareg women give to their husbands on trips. Was the first version of grigris designed for cables 10-11 mm, larger 8.9 mm can be used with the 2011 follow-up version published Grigri 2 ropes with a diameter.

Operation

The device works like a seat belt in the car. With slow pulling the cable run is not blocked. A mechanism is activated, the completely blocked the rope - A sudden, jerky cable is - without operator intervention. The Grigri operates according to the "all or nothing " principle. A stepwise regulated braking the rope run is not possible.

( To Drain a climber again) To release the locking mechanism back or disable (to allow fast rope pass), the lever must be pulled or pressure on the back lever part be exercised. In this state, the device does not brake. To activate the braking mechanism again, the climber must release the lever or pressure point.

Benefits

• The device blocks the rope in case of fall independently, without the assurance person must keep active. This has the advantage that the equipment continues to hold a fall if the belayer 's hands on the rope has not (eg because it stops during the backup on the wall or even loss of consciousness due to rock fall ).
• The belayer can hold a constant rope hanging person without effort.
• The rope does not crane gelt.
• The unit is very safe when used correctly.

Disadvantages

• The appliance is dangerous in case of insufficient user training. Therefore, it always comes back to accidents due to incorrect application.
• The device always blocked completely in a fall. A regulated braking is about the Grigri even impossible. Thus, the dynamic back up is limited.
• Too little rope diameter ( at Grigri 1 below 9.8 mm) blocked the device no longer completely, especially when the rope is new.
• The device blocks only a jerk completely (like the seat of a car ). If the device receives no jerk ( because of special rope course, friction, climbers ' sits ' on the rope ) does not block the device may and the rope slips through.
• The device is compared with Tuber and descender relatively heavy and lets only certain diameter of a single rope to. The use of double or twin ropes is therefore not possible, abseiling is only on single rope possible. Therefore, the use is often limited to climbing parks and halls.

Application Error

• The lever to release the locking mechanism is operated without an additional protection to the brake hand. This is both when draining as well as during fast rope outputting an error.
• The Grigri is when backing up or cable output with the hand. This allows the Grigri not rotate freely and the locking mechanism is overridden.
• By gross motor evoked too fast to drain the belayer. By conditional, carefully opening the Grigri the velocity can be determined.
• In a surprising fall by the above error, the hand pulls the lever to release the blocking reflex even more on what the fall accelerated.
• The brake hand leaves the rope in the condition of the blocked rope. This is a mistake that often more experienced climbers who secure without hand on the rope. You trust that the locking mechanism holds no fault of their own. But this is not always the case. When the rope is released is charged ( by a short relieving the Secured ) and then not jerky, but slowly increasing, it may happen that the locking mechanism does not work completely.
• The rope is incorrectly inserted into the device. In this state, the lock mechanism does not work.

Since improper applications occur through lack of training and repeatedly led to accidents, backing up with the was and even prohibited (along with other semi-automatic ) in individual climbing gyms for extremely safe device. The fact that such bans are not based on objective data collected shows a large study on the indoor climbing, also, on the basis of standardized observations to inappropriate behavior, the question of the influence of the hedging instrument examined the likelihood of an accident. Here, the widespread aft section with 40 % errors from clearly worse than the Grigri with 28.6%. The authors concluded that the dangers of Grigrisicherns are significantly lower than expected and are generally overestimated. A study published by the DAV in 2013 Kletterhalle study showed that with semi-automatic machines ( including the Grigri ) can be made much less dangerous backup failure (less than 0.2 dangerous errors per backup operation ) than, say, with the tuberosity (more than 0.5 dangerous errors per backup operation ).

Correct operation

Despite the above- mentioned disadvantages and application errors can with the Grigri, with the exception of some limited dynamic backing up, be very well secured. The following aspects have to be considered:

• Partner Check the correct cable insertion
• Lead climbing with gasworks Method: The brake hand on the rope remains constant while harnessing the possibility of lever pressing for an easy, safe and fast cable output for hooking the belays.
• The brake hand remains on the rope.
• In the event of a fall the belayer goes a step forward if necessary so that the fall - in the sense of securing dynamic - will not be slowed abruptly.
• In the event of a fall the belayer is ready and adept at fending off impact against the wall with his feet.
• When draining the blocking is achieved only with closed brake hand under the unit.
• Operation of the device is learned and practiced under expert supervision.

Grigri 2

The so-called Grigri 2 was published on 1 February 2011, more than 20 years after the appearance of the original. It is compatible with all UIAA single ropes 8.9 to 11 mm thickness (optimized for ropes from 9.4 to 10.3 mm). In this case, the backup device now has 20% of its former weight ( now 185 g) can be saved and 25 % of its original size. In June 2011, a portion of the previously sold units was recalled because the brake lever may be damaged under certain circumstances and, consequently, the brake assist of the backup device no longer works correctly. The Grigri works in this case as a tube. Petzl increased then the resistance of the brake lever for newly manufactured equipment.