Ellis Posted January 16, 2006 Share Posted January 16, 2006 AFAIK, there is no standard for safety bonds. There is, however a standard for lanterns that specifies a test, doppping the lantern a specified distance and it being stopped by a safety bond a specfied number of times without anything falling off (I am sure someone here can give the BS number and the specified values). This gives an indication of the number of incudents a safety bond should be able to handle at its rated SWL. As for identifying safety bonds that have been involved in incidents, this raises the LOLER requirement for labelling and record keeping. While safety bonds are not lifting equipment, it is probably worth treating them (and possibly hook clamps as well) as such. If they were lifting equipment, each item should be labelled with the manufacturers mark, a SWL or WLL, and a unique identifier. In your records, you should have a certificate to show the SWL/WLL which bears the same unique mark, and certificates of periodic testing. When a bond is shock-loaded, it should be quarantined and a note made on its record until it can be re-tested. Hired equipment should be accompanied by a file containing copies of the hire companies' records and should be similarly annotated if there is a shock loading and the item labelled as such and returned. This does raise one issue - I asked a well known theatre equipment hire & sales (who also do health & safety consultancy!) company for certificates for some safety bonds I purchased. Their response was that they did not have any and that they had never been asked for one before - the heat-shrink label on the bond has a weight limit. Since many venues do not hold such records for their flying equipment, I suspect that it is ging to be a long time until this is common practice! P.S. Moderators: Should this not really be in the Safety forum! Link to comment Share on other sites More sharing options...
ianl Posted January 16, 2006 Share Posted January 16, 2006 If that fixture had failed, then the lighting lads should have reacted with a question of "why" as opposed to wondering "how quickly can we get it back in the air". If I had been on a job and that had happened, and my main priority was to get the fixture back in the air, I would have been sacked on the spot by the boss. If the unit has failed with those fixings, how on earth can someone be stupid/incompitent enough to then return the unit with its original fixings to the air. Those fixings (and by that I mean the clamps, not the safety bond, as that has done its job of protecting the fixture from falling) are obviously not up to the job of holding the unit-as has already been proven-so to reuse those same fixings again is surely dangerous? but it's not just why did that fixture fall, possibly more importantly is are all the other fixtures in a similar state and likely to also fail. I would strongly condsider inspecting all the other fixtures in the rig for similar faults before opening Link to comment Share on other sites More sharing options...
Captain Posted January 16, 2006 Share Posted January 16, 2006 just out of curiosity, are you planning on pursuing this further with the lighting company? would it perhaps be good to make them aware of this thread? (although none of us would like to see you jeopardise a working relationship)Give them a chance to share their point of view as it were, and given that the general consensus, so far, seems to suggest that it was not the most sensible course of action, hopefully help them should a similar unfortunate incidents occur. Link to comment Share on other sites More sharing options...
Tomo Posted January 16, 2006 Share Posted January 16, 2006 I've always considered safety bonds to be one-use-only items. Stretching of a steel wire is almost impossible to spot, and has a very significant effect on its strength.Not to mention that shock loads are very difficult to quantify. Given the price of a new one, I don't think it's worth the risk or the time and effort required to re-inspect. Link to comment Share on other sites More sharing options...
landy Posted January 16, 2006 Share Posted January 16, 2006 When I spoke to the nice people at a safety bond manufactures I was told they sell two types of bond, the cheaper used, binned type and the more expensive used, visually inspected, use again. And no I don't know if they look different! Link to comment Share on other sites More sharing options...
Simon Lewis Posted January 16, 2006 Share Posted January 16, 2006 Was I wrong to air my disopproval? No, you had a duty of care under the Health & Safety at Work Act 1975 to point out where you considered a risk to exist. It could even be argued that this was a "dangerous occurence" under RIDDOR. what would you lot have done? Hard to say - like many situations it's easier to shrug shoulders and walk away. Making a fuss can cause all sorts of problems, lose you the job, the money and get you a "bad name". However, your report of the event suggests a nonchalent attitude from the company in question.For a thread to strip, there must have been incorrect components, damaged components or some other fault or incorrectly rigged component present. As several have pointed out, such actions would suggest a lack of safety culture, and a cavalier attitude. Items such as child safety seats and crash helmets are not recommended for re-use, nor is second hand sales of such items recommended as the history cannot be verified. Chris Higgs has a "demo" harness that has been subject to a fall with a test weight. It would not be considered safe for re-use, but it still looks brand new, with only the very slightest marks to suggest that it has any damage. His point is that the damage to such devices is often invisible or easily missed, and inspection/record keeping of use etc. is essential. Had it been me, I guess I'd have done the same - expressed my concern, and my astonishment that the fixture could be re rigged using the same bond. If such actions go unchecked, the next time you work with them, you could have the fixture drop on you! Link to comment Share on other sites More sharing options...
bellamy Posted January 16, 2006 Share Posted January 16, 2006 I can't see how those clamps would fail unless they have been hung by someone unqualyfied ore someone sleeping on their job. That would explain their defensive attitude towards you, and why they would just put the unit back up. Link to comment Share on other sites More sharing options...
johnhuson Posted January 16, 2006 Share Posted January 16, 2006 StrandGSX I'm still very curious about how two clamps managed to fail, did you manage to get a first hand look at what had failed on the fixture? Did they just replace the bolts if thats what failed. Also in some of your posts you've talked about a clamp failing implying a singular. Was this fixture hung from one or two clamps? Link to comment Share on other sites More sharing options...
JohnPartridge Posted January 16, 2006 Share Posted January 16, 2006 I think what strandgsx said sums it up exactly. "a few quid for a new bond is nothing compared to what it would cost if someone was killed," And yes , if I saw someone using equipment where it is uncertain weather it is safe or not I would go spare as well ( your not alone ) Most Steel wires are designed to take 1 strong shock, don't know why someone would want to risk another, where the result could be fatal. My £0.02pJohn Partridge Link to comment Share on other sites More sharing options...
strandgsx Posted January 16, 2006 Author Share Posted January 16, 2006 hey peeps, to answer and hopefully give a better picture. I didnt see any damaged bolts etc, they just proclaimed it was a stripped thread. However it looked like they were only using one clamp, cant be shure if it was a hook clamp or not as I wasnt close enough (diddnt want to be near a bunch of shambolic lunatics anyway). they knew who I was so diddnt want me any where near as they thought id cause a fuss. rigging technique was slightly shabby anyway, not much was done to the book including the electrics. Some of the more worrying things are not only that they re-rigged the fixture using the same bond but their rigging of the truss itself was something to be seen to be believed. On one rigging point there was a mass of chain and safety bonds holding up truss with 64's and those cheapo acme movers on it. its bad times at the moment, I see many new companies springing up who dont have much of a clue (they tend to spawn from mobile dj's) anyway iam not bagging anyone but I cant abide the way its done by the cheaper company. I sent an email to their office letting them know I wasnt very pleased with what I saw, the reply would be posted but its not polite enough for the good members of the blue room. I was basicly told to get stuffed sideways with the largest object I could find. why oh why do I bother Link to comment Share on other sites More sharing options...
Ynot Posted January 17, 2006 Share Posted January 17, 2006 AFAIK, there is no standard for safety bonds. There is, however a standard for lanterns that specifies a test, doppping the lantern a specified distance and it being stopped by a safety bond a specfied number of times without anything falling off (I am sure someone here can give the BS number and the specified values). This gives an indication of the number of incudents a safety bond should be able to handle at its rated SWL.Hang on, though - as I said earlier, wasn't the main reason for the industry swapping out chains for steel wires BECAUSE you could supposedly stress test a bond without rendering it useless...? (Within spec'd limits).As for identifying safety bonds that have been involved in incidents, this raises the LOLER requirement for labelling and record keeping. While safety bonds are not lifting equipment, it is probably worth treating them (and possibly hook clamps as well) as such.Another interesting discussion, perhaps - how many of us would be honest enough to say that they did NOT keep records of all bonds they hold in their stock, especially those in pemanent installs? I know that we don't, and I suspect it would be a near impossibility to keep tabs on all the bonds we have, as they seldom go out on the same lantern twice! (An argument there, I suppose, for zip-tieing the bond to the lamp for ID purposes).This does raise one issue - I asked a well known theatre equipment hire & sales (who also do health & safety consultancy!) company for certificates for some safety bonds I purchased. Their response was that they did not have any and that they had never been asked for one before - the heat-shrink label on the bond has a weight limit.And exactly how does a hire company test each bond as it comes back from a job? Do they? I'd hazard a guess that maybe some or all don't do it every time, but may test them periodically, but they would in no way be able to tell if one had been subject to a drop unless there were physical signs of wear & tear....Since many venues do not hold such records for their flying equipment, I suspect that it is ging to be a long time until this is common practice!I'll be undergoing a full LOLER check soon, and will certainly be asking the questions....P.S. Moderators: Should this not really be in the Safety forum!Probably....! :( Link to comment Share on other sites More sharing options...
Tomo Posted January 17, 2006 Share Posted January 17, 2006 Hang on, though - as I said earlier, wasn't the main reason for the industry swapping out chains for steel wires BECAUSE you could supposedly stress test a bond without rendering it useless...? (Within spec'd limits).I was under the impression that it was because chain can be broken easily if it is twisted in the wrong way - stick a bar through a extra loop of chain, and twist it around - the chain will snap. Steel wire doesn't suffer from this as much as it is inherently more flexible. Link to comment Share on other sites More sharing options...
niclights Posted January 17, 2006 Share Posted January 17, 2006 One clamp & moving heads is a very stupid thing to do. Hitting an endstop or a sudden change in direction will initially transfer the turning motion onto the clamp bolt. There is a good chance that the bolt will become lose quite easily! Link to comment Share on other sites More sharing options...
Nick S Posted January 17, 2006 Share Posted January 17, 2006 I've never seen a Mac 500 that's been hung with just one clamp - the specification clearly states it should be hung with two. If, as it sounds like you're describing, they were only using one clamp, I'd be very concerned. Link to comment Share on other sites More sharing options...
Ellis Posted January 17, 2006 Share Posted January 17, 2006 As I understand it, the main reason for moving from chains to bonds is the method employed to attach the clip to the chain. The metal hook bent around the chain can open up very easily. I believe the reason for moving to steel wire (rather than an improved chain design) was partially to allow old and new to be easilly discriminated. Link to comment Share on other sites More sharing options...
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