Rigging protocols

Our old training officer thought we should have some proper protocols about how to best rig for a certain number of possible situations we might encounter in actual rescues. And he wanted to do a session to go through at least one. When it came to it, not many people were available. But I was! I wasn't quite sure what to expect. I am not a rigger and I'm not of a mind at all to become one.

We met up on the parking lot. There were only four of us! But that’s ok. We distributed the kit and walked to the entrance. There is a pitch not far in that we’ve used before. There was a group of punters coming past, so we first got out of the way and started thinking of some ways of distributing force over a rig. We always try to rig in a way that every component part in itself is redundant; every single point should be able to fail and the rig should still hold. If you get several points of failure, things can really go wrong, of course! But you want to avoid failure as well, so we were thinking of how to distribute tension over ropes and kit in the best possible way. A knot weakens a rope, but it can result in one point of failure not leading to catastrophe, which without the knot could happen. Two carabiners is stronger than one, but if they end up rubbing against each other, you might be better off with one after all. That sort of questions!

Then we put it all to the test. We rigged a fairly simple haul. A Z-rig (which uses pulleys or a similar to make sure you in effect haul only about a third of the weight you pull up) with a releasable deviation. The idea is that you want to stand on level ground and pull the rope in horizontally, but of course this rope has to go through pulleys fastened close to the ceiling, so you might pull the rope horizontally, but you are are lifting the casualty vertically. Once the casualty has reached these pulleys, though, you need to be able to lower these pulleys, otherwise you can't pull the casualty into the level. 

We had a good look at how we were going to do it. We also wanted to make sure that one person would be able to lower the casualty down, if necessary. And we had incorporated some tension meters, so we could check how much force would actually be exerted on several components of our rig.

Then it was time to put it to the test. I was going to be the casualty, and Gethin would be suspended from the ceiling so he could work the releasable deviation. That worked fine. And the forces we exerted on the whole set-up were quite modest. There is a bit of a risk of strong forces when you are having a weight on a sub-horizontal rope. And that is the situation once you are starting to pull the casualty into the level. But it was all perfectly fine! All the kit is guaranteed to several times this force. That was good to know. And necessary, of course; casualties can be a lot heavier than I am, and they may well come with the added weight of a stretcher.

All the rope work by the ceiling; I think it shows we have everything double… and notice the tension meter.

We also tried it with someone else suspended from the ceiling. And we tried it with nobody suspended from the ceiling; could the same work not be done from a distance? And the answer was: yes it can! Which is good, as being suspended isn't very comfortable.

Me being hauled into the level. Notice as well the iPad on the rocks; this is giving a read-out of one of the tension meters…

We also had lunch somewhere in between our experiments. But when we had tried all this, we decided to de-rig and call it a day. That wasn't even trivial! Some of the knots we had been using are a bit of a pain to undo. And removing the kit from the ceiling there is only simple if you are quite tall and you have contempt for heights. 

I think it was a useful session! As I said; I do not aim to become a rigger. If I am at some point in control of a rescue, I will delegate. But if I would be in control I would have to make sure the rig is as good as it can be. And being able to quickly and skilfully put the thing in position, is quite a different skill from being able to look at it from an angle of pure physics, and spot if there are any weak points in the system. I really think I have practised that second skill.

When we were done I politely asked the men if they were okay to carry the kit down from the entrance. I knew Miles was in his underground accommodation, and he had suggested I pop down for a cup of tea at the end of our session. And that seemed too good an opportunity to miss. And the men were okay with that (I did carry my share up to the entrance, and from there it is downhill all the way) so at the gate I said goodbye.

I then went back down, as far down as you can get without needing diving equipment, and indeed found Miles, in the process of repairing a light switch. It was good to see him! We had a lovely panad together. But I didn't linger; a bit more than half an hour later I was on my way again. I went back the other way around. It had been a long time since I had been in these recesses of the mine!

The Deep Sleep; notice Miles in the corner making me a cup of tea

If this sort of situation crops up more often, maybe I should sometimes schedule some time to just wander around. I pretty much forgot how the whole mine hangs together. And it is still an amazing place to explore. I could imagine we want to go back in to practice more plausible scenarios! And then we have documented Best Practice for all of them…