bigclive Posted November 6, 2014 Share Posted November 6, 2014 So which individual would you blame and why? This is probably best answered by seasoned riggers who earn most of their income from rigging and may even have used a similar hanging technique. The carabiner was probably chosen to allow quick attachment of the frame to a hoist during a show. But in hindsight, how would you have got round this? A secondary bow shackle so the carabiner only saw the vertical load, but the bow shackle then split that off to the frame attachment points? What if you were asked to arrange something similar on a touring show knowing that even in the most extremely random failure you would be held liable. Link to comment Share on other sites More sharing options...
trussmonkey Posted November 6, 2014 Share Posted November 6, 2014 ooh now thats a question that will open a contentious discussion. in my hypothetical humble opinion (and this is only my opinion and I do not wish to cast blame on anyone) the fault lies in 2 places. Ultimately the head rigger/rigging designer is at fault if they specified a karabiner in this situation. If the Head Rigger/rigging designer specified something different and it was changed out on the road (as things do) then it is the fault of the touring head rigger for a)inappropriate selection of equipment and b)not getting the approval of the person who designed the rig. I would not have used the karabiner. if you cant resolve the forces in the piece of equipment that would be the first choice due to speed and ease of use then you have to look for another bit of kit no matter is production sream and shout saying it will slow the show down ! I would use a suitably rated bow shackle that then connects to a master link that has a further 2 master links already built in. A fairly standard piece of kit the master link assembly. They are more suited to angled loads (as is the bow shackle). as I say all my opinion in a hypothetical sense and I do not wish to cause offence to anyone reading this who was involved in the accident. and obviously I am speaking without knowing the intricacies of the show or the design. TM Link to comment Share on other sites More sharing options...
kerry davies Posted November 6, 2014 Share Posted November 6, 2014 Clive, on the thread about Factors of Safety, Seano has posted a pic of a quad-axial suspension using shackles and "O" ring which is similar to what OSHA reckon should be the method. Carabiners, as you say, are used as quick-fix methods in straight lifts but tri-axial is outside MIs. It also appears from the video that they linked carabiner to carabiner to carabiner which, again, is in contravention of MIs. (I may be wrong because the view is not that clear to these old eyes.) I have a sneaky feeling OSHA went only as far as that and is why Ringling used the specific phrasing; "...we disagree with the agency’s determination that the way in which the carabiner was loaded was the sole cause of the accident..." The $7,000 is neither here nor there, this is the US and an entirely different legal culture. The punitive element has yet to start and the compensation will be huge. The civil case now has a precedent of guilt, unless appealed, and the settlement of the class action that much quicker. The blame game will continue but in essence all the "victims" need is that OSHA has found the employer guilty and they pay. Vicarious and subsidiary claims on Head Rigger/Designer/Crew Chiefs etc will be something Ringling and/or their insurers take up. They might also take a case against the manufacturer as the "sole cause" wording suggests they think the carabiner was "faulty". What I think we need to take from this is two lessons. One is that we need to be able to prove "competence" in everything we do and the other is that MIs are to be taken very seriously indeed. Knowing them would be handy!(Neither a rigger nor a lawyer so just opinions) Link to comment Share on other sites More sharing options...
Seano Posted November 6, 2014 Share Posted November 6, 2014 But in hindsight, how would you have got round this? A secondary bow shackle so the carabiner only saw the vertical load, but the bow shackle then split that off to the frame attachment points? Maybe. Though a bow shackle is also slightly limited in that it ideally should not be loaded in just any direction. (Place it pin uppermost on a clock face - the loads should be imposed only at 12 o clock, and between 4 - 8 ish.) So it might be necessary to take some action to ensure it can't rotate and end up sitting sideways or something. In practice, with a decent quality screw-pin anchor shackle, that's a bit of dodgy practice you'd be very unlucky not to get away with, but nevertheless.. An O ring or pear ring might be better. Or possibly the kind of rigging plate generally produced by carabiner manufacturers for roped access, rescue and arboriculture.. (This kind of a thing for example, or like this.) What if you were asked to arrange something similar on a touring show knowing that even in the most extremely random failure you would be held liable. I realise the law is occasionally an ass, but it would be nice to believe that a person would only be held liable if they actually were negligent in some way. Not for something that could not reasonably have been foreseen or prevented. The sudden failure of an apparently undamaged and correctly specced piece of equipment for example. (A liability for the manufacturer perhaps but not, one would hope, for the purchaser.) Maybe I'm being hopelessly naive. Link to comment Share on other sites More sharing options...
trussmonkey Posted November 7, 2014 Share Posted November 7, 2014 I dont think a karabiner used in this way is correctly spec'd. they are not designed for 3 way loadings and all of their strength is along the major axis (spine). As to where blame actually lies that is a grey area. something like this would have been more suitable Master LInk Assembly heres a great thread on a rock climbing forum about tri axial loading. they take the OP apart but lots of replies explain it. Tri Axial Loading Link to comment Share on other sites More sharing options...
Seano Posted November 7, 2014 Share Posted November 7, 2014 I dont think a karabiner used in this way is correctly spec'd Nor do I. (Didn't look like I was suggesting otherwise in my reply to Clive did it? If so, I didn't mean it to.) Link to comment Share on other sites More sharing options...
trussmonkey Posted November 8, 2014 Share Posted November 8, 2014 sorry I thought it did... my bad :( Link to comment Share on other sites More sharing options...
Seano Posted November 8, 2014 Share Posted November 8, 2014 Aha. No worries. :) I had a read of that climbing forum thread, but it's getting a bit old and seems to have a lot of broken links to images and wotnot - struggled a bit to follow it without the pictures. Link to comment Share on other sites More sharing options...
trussmonkey Posted November 9, 2014 Share Posted November 9, 2014 found some more links . Here 1 Here 2 Link to comment Share on other sites More sharing options...
Seano Posted November 9, 2014 Share Posted November 9, 2014 Here 1 That's interesting, but a bit too dogmatic imo. Other sources will tell you just as authoritatively that it's certain death to ever tie any kind of a knot in a dyneema sling. The dangers are real, but those sources are too dogmatic also. All a bit nuanced innit. (Regarding rock climbing that is - doesn't have any bearing on the subject of this thread really, we've gone OT now.) Link to comment Share on other sites More sharing options...
timmeh2 Posted November 9, 2014 Share Posted November 9, 2014 Hi I suspect there is an awful lot of fingerpointing and witchhuntery going on behind the scenes that we're unaware of. The absolute priority for the manufacturer is to prove that it was operator error rather than equipment malfunction that caused the accident. I'm all aware of loading 'biners in the wrong way so much that it's best not to apply loads that could pull the gate open and break the open end. What is true is that loading a 'biner sideways will reduce its strength, not magically drop it to 0kN where a fail is guaranteed. I wonder if a bit of skullduggery has been done as the company under fire is massive and 7000 dollars isn't going to be too hard for them to swallow. All the bestTimmeh Link to comment Share on other sites More sharing options...
mac.calder Posted November 9, 2014 Share Posted November 9, 2014 7k is only the fine issued.... There will be civil suits filed by the families affected, you can almost guarantee it. Being found culpable by the investigators means that most of these families will probably get rather large settlements with minimal fight - the main squabble will be over the value of a life. Rather sickening really. Link to comment Share on other sites More sharing options...
Ynot Posted January 3, 2016 Share Posted January 3, 2016 A bit of thread resurrection...Whilst not a direct statement about the Ringling incident, just found this article on 'The FlyWire' which has some interesting observations/comments on carabiner/shackle use. Link to comment Share on other sites More sharing options...
Seano Posted January 4, 2016 Share Posted January 4, 2016 just found this article on 'The FlyWire' That's a bit of a poor effort I'm afraid. There's a pinch of good stuff mixed in with a good deal of misconception and half-truth. For example it confidently asserts the old "microfracture" myth regarding aluminium 'biners in it's second paragraph, then debunks it again towards the end. For such a short article to flatly contradict itself is pretty good going. According to my dictionary btw, a "carabineer" is a cavalry soldier armed with a carbine. Link to comment Share on other sites More sharing options...
indyld Posted August 24, 2016 Share Posted August 24, 2016 https://www.osha.gov/doc/engineering/2014_r_05.html Link to comment Share on other sites More sharing options...
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