Influence of the belay device - Petzl Canada

Influence of the belay device

The results presented above correspond to falls belayed on a GRIGRI 2. In order to determine the influence of the belay device, the same falls were redone with a REVERSO 4 replacing the GRIGRI 2. The test protocol is unchanged: the only variable is the belay device.


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The results are influenced by slippage in the belay device and therefore by the belayer's grip. Variability is thus high: these results cannot be generalized to all situations and allow us only to quantify, in a broad sense, the influence of the belay device.

Influence of the belay device 1
Influence of the belay device 2
Influence of the belay device 3
Influence of the belay device 4


Slippage in the REVERSO 4 has the effect of limiting the forces at work. The difference between GRIGRI and REVERSO 4 can be significant: up to 30% less force on the anchor.

The climber experiences a softer catch with the REVERSO 4 in these configurations.

The impact on the belayer is reduced, the force is weaker due to rope slippage. However, control of the rope, and thus stopping the fall, remains dependent on the belayer being very alert.


The belay device should be suited to the situation.

Slippage in the REVERSO 4 increases climber displacement: one must be especially vigilant where there is a risk of hitting the ground or a ledge. This slippage can make stopping a fall particularly difficult for the belayer: gloves must be used, especially with a new skinny rope.