bazza123:
You mentioned falling with a harness, but think about it, abseilers and those doing a high altitude high opening parachute jump would wear a harness or a lot longer than fifteen minutes. The problem seems to occur when blood flow is restricted to individual limbs. Wearing a harness that fits round the hips/groin would be ok I’d have thought, as it wouldn’t be compressing any arteries as such■■?
I don’t understand why it took an hour for lifting gear to arrive.
Hey Bazza123,
Think you misunderstood me mate, I meant falling with a harness whilst clipped on e.g. scaffold or MEWP etc. Do you wear harnesses?
If not I’ll try to explain as I used too and I am having to again, but I’m not professional enough to explain it technically so I’ll do it as I understand it.
You can wear a harness all day long mate with no issues, I used to on the underground and in the sewers for like 12 - 14+ hours, you just have them done up tight, but comfortable in case at any moment they are needed in an emergency and you need to be recovered.
If you have them done up tight you won’t slip out of the harness either!
Ask how that happened in one of my training sessions for me to know this fact. And for men this is even more important so you don’t lose your testicles (as in physically rupture and pop them out the skin) etc! 
The problem is whilst you are moving around on the ground, your body isn’t affected by the harness, its a bit constricting to due it being a snug fit etc, but not that bad either.
However when you are floating within mid-air, with no support underneath relying on your harness to prevent you falling to the ground here cometh the problem.
Usually depending on the harness you usually only have one clip point fixed to one point on the harness hence you are just hanging like a leaf on a tree if the unfortunate happens to you.
This is where dreaded suspension trauma is likely to occur, as you rightfully said wearing a harness is always likely to go through your legs and tighten around your groin and obviously closes around your shoulder and hips, so you don’t slip out.
However in your groin there are actually quite a few important arteries and veins in there serving your whole body and keeping you alive.
So when suspended in midair the harness is literally crushing your groinal area and hence compressing them artieries. All the toxins then build up in there as your body can’t clean them out as the blood supply is constricted and hence during this time you usually faint too, quite quickly.
However the dangerous bit is when you are freed, the constricted/compressed arteries/veins are suddenly able to flow again, but now with all the toxins the flow around your body and of course shut down and poison your vital organs. Hence you need to be given a specific injection prior to be released if you are suspended and have been up there for over say 15 minutes, obviously each person is different.
As for the knife a lot of scaffolders and steelfixers swore by it. On a big steel project we practiced our rescue plan (with a dummy), if someone remained conscious you’d hope you could coax them to create a seperate standing loop with rope which to support themselves until you could get it sorted so they could relieve the pressure off themselves and by us on the ground enough time to get a MEWP over or the rescue plan enacted.
However like the dummy if they were unconcious the quickest we ever got the rescue plan enacted and to the casualty was 11 minutes and that was with all the resources close by, technically no good as they’d be close to having suspension trauma and would be very ill even once rescued. It was even commented that even at that speed we’d have to seek guidance from a emergency operator whether to release or leave them up there until we could get a paramedic up there to give them an injection and then release them.
Back to the thread a crush victim would most probably suffer the same time of physiological problems as suspension trauma, hence they don’t want to move stuff straight away and make the situation worse!
C
Edit - Corrected atricious spelling and grammar - Stupid smart phone operator!