The choice of karabiner comes down to its intended use. All karabiners are certified for use on their major axis with the gate locked. Foreseeable misuse is catered for on the other axis.
Loading a karabiner in the following ways can be dangerous and could lead to the failure of the karabiner due to a loss of strength of 70% or more:
- Open gate
- Minor axis
- More than two directions
- Over an edge
Pressure and rubbing against the locking sleeve can not only open the gate but can also create a dangerous situation as the sleeve is the weakest part of a karabiner.
Load direction (shape)
Device(s) it’s being used with
D shaped – to position the load in the strongest direction.
Oval – symmetrical shape for even load distribution.
Pear – for high capacity / bulky items.
Wide opening – for attaching to anchors.
Multidirectional – for loading in more than two directions.
Karabiner Gate Action
|Can be opened with one hand||Vibration can lock the sleeve|
|Reliable in dirty / harsh conditions||Rubbing can unlock the sleeve|
|User manually locks the sleeve||User forgets to lock the sleeve|
|Rapid autolocking||Difficult sleeve operation|
|Secure triple action locking||Two hands needed to insert a device|
|Chance of something stopping the sleeve locking|
|Foreign objects can prevent locking|
|Ease of opening||Cantilever loading|
|Rapid autolocking||Pressure from structure can open gate|
|Two separate actions|
|Very secure||Tool required for connection / disconnection|
|Speed of opening||Two hands needed to insert a device|
|Rapid auto-locking||Chance of something stopping the sleeve locking|
|Rapid auto-locking||Two hands needed to insert a device|
|Visual locking indicator|
|Helps prevent inadvertent disconnection||Tool required for connection / disconnection|
|Secure triple action locking|
As you can see, there is generally a compromise between security and ergonomics.
Some manufacturers give guidance on which karabiners to use with which device. They also produce accessories to ensure the correct orientation / position and to avoid cross-loading.
EN 362 Personal protective equipment against falls from a height. Connectors.
EN 12275 Mountaineering equipment.Connectors.
UIAA 121 Connectors.