Concerns have been expressed within the BMC’s Technical and Training groups that misuse and inappropriate use of belaying devices is becoming a major factor in accidents and near misses both indoors and out.
The subject was discussed in depth at the 1997 Technical Conference and some results of that discussion are described here. Whilst touching on good belaying practice this article is principally concerned with describing how belaying devices work, and how the design, properties, and appropriate use of the devices are related.
For practical purposes an attempt is made to group belaying devices into broad bands according to their relative properties, and then relate these groupings to appropriate use. Greater detail on ‘Good belaying’ canbe found in both the BMC’s Rock Climbing Video and the series of advice posters.
Modern climbing is multi disiplinary in nature and the demands put on a belay device whilst sports climbing for example, are very different from those experienced on adventure routes. Belay devices of different designs can have radically different properties and this should be taken in to consideration before use. However for the prospective purchaser, faced with a bewildering array of devices, there is little information availiable that makes clear the important differences between devices and what this might actually mean in practice.
The following observations, from trainers and wall managers, show how and why this is becoming an increasingly urgent concern:
- Users are not aware of the differences between devices.
- With many near misses it is only a matter of time before more serious accidents occur.
- A high proportion of accidents occur as the belayer loses control whilst lowering the leader.
- A common fault is to use too thin a rope in a dcevice which is sensitive to this factor
- Locking devices being incorrectly operated or misunderstood are a major concern and seen as being the cause of many near misses.
- Locking devices being bought and used as novice devices.
- Most incidents involve experienced climbers.
- Walls are perceived as a safe environment and so climbers do not pay as much attention as outside.
- Retailer knowledge and advice could be improved to ensure appropriate devices are purchased.
- Incorrect choice of karabiner can compound problems.
- Novice climbers look to what wall staff use when choosing a device of their own.
- Climbing walls are often less forgiving of poor belaying than the outdoors.
- However all belay devices will hold a fall if being correctly operated and an appropriate diameter rope is being used.
The above paints a complex picture with a variety of interrelated factors contributing to serious accidents and near misses.
How do belay devices work?
Belaying devices use a combination of friction and pinching to produce a braking effect on the rope and a device’s design dictates which effect will predominate upon loading. Devices relying principally on friction (e.g. Figure-of-8) will tend to be smooth running and are entirely reliant on the belayer reacting quickly by providing a controlling force on the rope and thereby forcing it into the optimum braking configuration.
Devices producing a strong pinch effect will tend to grab the rope and lock up under load. They also require skilled use particularly when paying out rope but are ‘helpful’ to the belayer when dealing with high forces or unexpected falls.
Flat plate devices such as the Stitch plate, whilst giving a braking effect via friction, also give strong pinch effects when loaded and correctly operated.
Some devices have very little friction element and operate solely by pinching or camming the rope, a typical example being the Gri-Gri.
Discussing the properties of belaying devices would be a lot easier and clearer if they could be grouped into descriptive categories. The catagories shown below were defined at the 1997 Technical Conference;
Intermediate, Slick, Grabbing and Locking devices:
Slick: Such devices rely principally on friction to provide braking. Devices of this type allow smooth, quick rope feed and are less likely to jam when rope is being paid out. They require more care on the part of the belayer in applying and maintaining a controlling force when arresting a fall or during a lower.
Intermediate: Devices neither particularly slick nor grabbing. Good general purpose devices.
Example: Sprung Stitch.
Grabbing: A device giving a sharp braking effect when suddenly loaded. Likely to be pinching devices. Care needs to be taken to ensure smooth rope feed, otherwise may jam. Have a tendency to lock up easily. Effective at holding falls which may not be anticipated by the belayer and or where a high controlling force is required.
Example: Flat Stitch.
Locking devices: Are not friction based but rather lock the rope via a camming action. Ability to hold falls not dependent on controlling force of the belayer. To be effective they require load to be applied rapidly. Should not be regarded as automatic devices. Tend to be particularly sensitive to rope diameter. Although effective in holding a fall, require care and skill in use particularly when lowering. Example: Gri Gri. Devices which can provide some frictional braking but reconfigure to lock under load by a pinching action are a subset of the catagory.
Example: Single Rope Controller.
So belaying devices act in different ways and can be described as shown in the box. But how do you select the appropriate device for a particular use? You need to look at the factors that are likely to come into play during use and choose a device the is going to give the best performance in these circumstances. Here are some suggestions.
The following factors would suggest the use of a grabbing device:
Heavyweight Lead Climber
An environment where the belayer may be distracted
Quick rope feed not essential
The following would suggest the use of a slick device:
Thick or stiff ropes
Experienced attentive belayer
Quick rope feed essential
The following factors would suggest the use of a locking device
Experienced belayer with knowledge of the device
Solid runners and belay
Quick rope feed not essential
This article arises from concerns expressed within the BMC’s Technical and Training groups that misuse and inappropriate use of belaying devices is becoming a major factor in accidents and near misses both indoors and out.
Choosing the right device reduces the chance of an accident whilst belaying or lowering and makes for smoother climbing. However any device needs to be properly operated in order to be effective and so make sure you know how to use the device, pay attention and remember your partner is relying on you.
Grouping belay devices as Intermediate, Slick, Grabbing or Locking.
Exercise at BMC/ABMEM Technical Conference
Delegates were asked to order a number of belaying devices on a sliding scale from very slick to very grabbing. It was stressed that this was a relative comparison i.e. imagining use with identical ropes, krabs etc. The devices considered were: Sprung Stitch, Bettabrake, Variable Rope Controller, small tuber ATC, Bug, Fig-8, Cosmic Arrester and a small Black Diamond device.
After discussion, the devices were ordered as follows (from slick to grabbing): Fig-8, ATC, Bug, Tuber, VRC, Sprung Stitch, Bettabrake, Cosmic Arrester, small Black Diamond device. In addition it was found possible to group the devices into loose sets according to their properties. The Fig-8, ATC, Bug and Tuber were grouped as slick devices. The Sprung Stitch and VRC as intermediate devices and the Bettabrake, Cosmic Arrester and Black Diamond device as grabbing devices.
The Grigri was also considered and it was agreed that as a fundamentally different device, it should lie outside this scale and be described as a locking device. The SRC and Cassin Logic were also felt to lie outside these groupings and were best considered as a type of locking device.
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