In reply to gdnknf:
> I was recently criticised at a crag (can you believe it!?) for carrying my prussiks on a wire gate as it is 'dangerous'.
> I did start wondering WHY this chap had a problem with it and if anyone else felt the same way.
I am assuming the prussiks were racked rather than in use?
I have always tended to attach my 'rescue' gear to my harness with a screwgate. After dropping an approach shoe down Cloggy in 2006 (narrowly missing another party) I am now extremely wary of attaching things to the back of my harness with only a wiregate. As such, I would certainly recommend people don't use a wiregate for crucial items but I wouldn't go as far as to say it was ever dangerous.
FWIW I use a Grivel screwgate accessory krab (from their axe leashes, rated 650kg) to carry 2xprusiks, 5-10metres of 5mm tat, a tibloc and knife.
There is also the issue that if you rack prusiks on a wiregate, you might be tempted to use them with the wiregate rather than change to a screwgate. However, I think that is a very poor argument. There is no point in carrying an extra heavy, expensive screwgate that you won't generally use just to rack some bits of cord. Although, as said, my preferred solution is to use a lightweight but high quality screwgate accessory krab to get the best of all worlds in terms of weight, cost and security.
> Where and when do you think screw gates are appropriate/necessary in climbing (multi-pitch or single pitch)?
It is worth remembering back-to-back wiregates are generally a suitable alternative, but after a decade of instructing climbing, when I have this discussion I boil it down to 3 situations:
-
The krab is connecting to the harness (or rope loop).
(Due to the high risk of accidental opening i.e. ropes clove-hitched back at belays.)
-
The krab represents a single point of failure that will be (or is very likely to be) loaded.
(In short, "if it fails you die". This covers the obvious belay 'powerpoint' but can also be said to includes situations such as sport climbing where a quickdraw unclipping on a crux bolt would result in decking out.)
-
The krab is out of sight and will be (or is very likely to be) loaded.
(It is fairly obvious, but if you cannot see a krab, then just using a wiregate does not give much security. Abseil anchors and top-rope belays fall into this category.)
It is not an exact science and the three categories do overlap but I find they can help provide focus and get people thinking sensibly about things rather than just using screwgates by default.