Physics and Experiments demonstrating GriGri slipping in No-Hands Belay. Head to https://brilliant.org/hardiseasy to get a 30-day free trial + the first 200 ...
A good recent video from Hard is Easy on the GriGri belay device
My takeaway was that it CAN happen under pathological conditions (rope in compromised position, and you’re standing directly under your climber, rather than it’s something to worry about… Like, if you consistently abuse the GriGri, then the 0.1% chance of failure may eventually get you after 100s of abuses. But for the 0.01% of the time that you get knocked out by a rock, the odds of hitting that 0.1% chance of failure are astronomically low. And probably 0 if you were standing back appropriately and don’t have the rope sitting a crazy way.
My takeaway was that it CAN happen under pathological conditions (rope in compromised position, and you’re standing directly under your climber, rather than it’s something to worry about… Like, if you consistently abuse the GriGri, then the 0.1% chance of failure may eventually get you after 100s of abuses. But for the 0.01% of the time that you get knocked out by a rock, the odds of hitting that 0.1% chance of failure are astronomically low. And probably 0 if you were standing back appropriately and don’t have the rope sitting a crazy way.