andyscott Posted October 19, 2006 Share Posted October 19, 2006 Hi Everyone, Is it necessary to safety a chain bag? Andy Link to comment Share on other sites More sharing options...
MarkPAman Posted October 19, 2006 Share Posted October 19, 2006 What could happen if it fell off? Large amount of metal going downward? I'd RA that as needing a safety. Link to comment Share on other sites More sharing options...
andyscott Posted October 19, 2006 Author Share Posted October 19, 2006 Hi Mark, Sorry about this, but being new to forums and stuff...what is RA? :D I'm guessing your view is a "Yes they do" Assuming that it is (and not wanting to pre-empt any other posts) where do we safety from? Andy Link to comment Share on other sites More sharing options...
David Duffy Posted October 19, 2006 Share Posted October 19, 2006 Sorry about this, but being new to forums and stuff...what is RA? :D "Risk Assess" more than likely. Link to comment Share on other sites More sharing options...
andyscott Posted October 19, 2006 Author Share Posted October 19, 2006 Thanks David! Link to comment Share on other sites More sharing options...
Pete McCrea Posted October 20, 2006 Share Posted October 20, 2006 From my experience I've never seen a chain bag with the suitable points, or that had been designed to have a secondary safety attached to it. When rigging motors I undertake a visual inspection of the chain bag to ascertain whether it's suitable for the task (Is the stitching ok? Rips in the bag? etc etc...). If in doubt over the safety of suitability for the task, I reject the chain bag and replace it with a different and suitable one. Correctly rigged and set up by a competent rigger, I'd say that there is no need to safety the bag. The clip, wire or webbing, and bag section should have been engineered to be safe for the fall length of chain that the bag will hold. Therefore if used correctly the factor of safety should not be exceeded, and the bag should be fine. However if the bag isn't dressed properly then there is a chance that the chain can run out of the bag, causing the chain to dump, and potentially the softlink to fail causing the chain to come free of the motor body. Again it comes down to using competent staff, who know how to set up the equipment correctly. I would also argue that putting a risk assessment together that says it needs safetying is wrong and shows a possible fundamental lack of knowledge of the system, and therefore a possibility that the person writing the RA isn't competent to do so for that particular task? Can I ask why this question has come up? Link to comment Share on other sites More sharing options...
MarkPAman Posted October 20, 2006 Share Posted October 20, 2006 I would also argue that putting a risk assessment together that says it needs safetying is wrong and shows a possible fundamental lack of knowledge of the system, and therefore a possibility that the person writing the RA isn't competent to do so for that particular task? Guilty as charged! :) But then I'd never do a risk assessment over the internet. Last time I did any rigging was many years ago & I'm pretty sure the chain bags we used had two or even three sets of points on them. Link to comment Share on other sites More sharing options...
andyscott Posted October 20, 2006 Author Share Posted October 20, 2006 Can I ask why this question has come up?I was involved in a job where there was a lot of talk of safetying this and that while leaving obvious safety issues unresolved. It was getting late and I asked if they'd like me to safety the chain bags maybe? That was when the discussion started. From my experience I've never seen a chain bag with the suitable points, or that had been designed to have a secondary safety attached to it. When rigging motors I undertake a visual inspection of the chain bag to ascertain whether it's suitable for the task (Is the stitching ok? Rips in the bag? etc etc...). If in doubt over the safety of suitability for the task, I reject the chain bag and replace it with a different and suitable one.If we can rely on a visual check of the item to satisfy us that there is no need to safety why do we put them on everything else. Could we not just get away with saying "well the bolts holding the clamp to the yolk look fine." ? Just because something doesn't have it (an attachment point in this case) isn't necessarily an indicator that it doesn't need it. That's why I'm trying to find out and get people talking. Maybe it does need it and nobody has thought about it much because "It's always been like that".Correctly rigged and set up by a competent rigger, I'd say that there is no need to safety the bag. The clip, wire or webbing, and bag section should have been engineered to be safe for the fall length of chain that the bag will hold.I've never seen a bag with any kind of rating label attached to it (do they exist?) so I think I'd have a hard time knowing if it was capable of taking the load of a particular length of chain. Also, we know that a motor has been correctly engineered and that the parts inside the motor are capable of taking the load we place on them. We get our motors inspected and certified by competent people but we still put a safety on them. OK, now I really don't know what I think. :) Andy Link to comment Share on other sites More sharing options...
MartinGreen Posted October 20, 2006 Share Posted October 20, 2006 Also something to be considered is perhaps the fact that unless the safety is fitted very tight to the bag/motor isn't the bag just going to fall and it be a luck issue as to whether the chain spills out or not? Bearing in mind most bags are round, then putting a safety on one part of the rim would only encourage it to tip. Chain bags do not need to be safetied as I know and understand it. No standard or legislation requires it nor requests it. Hope this helps a little. Link to comment Share on other sites More sharing options...
andyscott Posted October 20, 2006 Author Share Posted October 20, 2006 Also something to be considered is perhaps the fact that unless the safety is fitted very tight to the bag/motor isn't the bag just going to fall and it be a luck issue as to whether the chain spills out or not? Bearing in mind most bags are round, then putting a safety on one part of the rim would only encourage it to tip. Chain bags do not need to be safetied as I know and understand it. No standard or legislation requires it nor requests it. Hope this helps a little. Hi Martin, Thanks for that. Now I hear you might know something about double braked motors...... Andy Link to comment Share on other sites More sharing options...
Pete McCrea Posted October 20, 2006 Share Posted October 20, 2006 I hope you didn't take that as a personal dig Mark, I'm sort of echoing points made in the oter post at the moment. Link to comment Share on other sites More sharing options...
MartinGreen Posted October 20, 2006 Share Posted October 20, 2006 I know a little here and there, but nothing that translates into anything other than foul and abusive language :) Link to comment Share on other sites More sharing options...
johnhuson Posted October 21, 2006 Share Posted October 21, 2006 Has any one considered one of the more likely things that could fail is the stitching of the bag? There is only one possible way to provide a secondary means of support (which is what the definition of a safety is) which is going to remove any risk of chain fall from bag failure. That is to have another slightly larger chain bag surrounding the standard bag and hang from a second independent point on the hoist. I think we'd all agree that, that's taking it too far! The line has to be drawn some where and safetying a chain bag is past that line in my opinion. A risk assessment is just that, an assessment of risk, weighing up the potential for an accident to happen with the severity of the accident should it ever occur. Providing that the chain bag supplied with the motor is used (which should be designed to support the weight of the chain) then the probability of an accident is very low and despite the potential severity being reasonably high this is still not a high enough risk to implement further measures. If the likelihood is high then why don't hoist/bag manufacturers provide a method of adding a secondary support is one question I ask myself. Though thinking about it this almost implies poor design in the first place. Another view, my feeling on half the reason for safetying lanterns for example is that there is potential for incorrect installation (improperly hung fixture or poorly installed hook clamp for example) as much as an actual hanging component failure. As a chain bag is (or should be) designed as one complete unit, with a spring loaded catch on the hook then the chance of incorrect use are significantly reduced, although not removed altogether! One question for you Andy just out of interest, where during this discussion was it intended to add a secondary safety? Link to comment Share on other sites More sharing options...
dave singleton Posted October 21, 2006 Share Posted October 21, 2006 I'm 100% in agreement with John there. I'm all for working safely (hell I even wear goggles for soldering) but I think some people do go to far with it. When ever I read an article about over safety I imagine people walking around with bubble wrap gaffered to every part of their body. I think you will proberly find that nearl every single case of lanterns falling etc is due to rigging errors rather than equipment failure. We did a show about 3 years ago now, where a Cantata profile fell from a lighting bar when a piece of set was flown in and somehow was left dangling by its cable (I stilll think its possible given the weight of a cantata profile but hey). The only logical solution we could come up with after checking the lantern throughly is that its hook clamp wasnt done up properly. Maybe a saftey would have helped had it not been rigged directly on the end of a bar. Link to comment Share on other sites More sharing options...
andyscott Posted October 21, 2006 Author Share Posted October 21, 2006 Hi, Just to clarify, I'm not saying that we should safety chain bags or not. I was just asking the question to see what other peoples views were. I'm not in favour of it because like many of you I feel there is too much legislation surrounding the entertainment industry and it's just one more safety to remember; apart from all the other very valid points that have been made so far. Some of the rules and regs. are necessary and haven't gone too far, but then there also seems to be a lot of legislation for legislation sake. There also seem to be a lot of people working in the industry who have taken the whole safety thing too far, and as is mentioned in another post on this forum regarding double braked motors (look it up, it's quite good) a lot of them don't really understand what they're talking about. This leads to the people who make the rules over compensating and not leaving enough up to Common Sense. Perhaps if we removed the 'safety net of legislation' we might get back to some normality. I'm not advocating unsafe practise or shoddy workmanship. What I am saying is that we might get the job done that little bit quicker if we don't have to jump through health and safety hoops all the time. As professionals we understand the risks, our limitations and the limitations of the equipment and it's frankly more than it's worth to do something that is obviously unsafe. Sorry if this is re-stating what other people have already said. So, The risk of the bag falling is low, if the bag is properly constructed (fitness for purpose). The bag should only be fitted by a competent person (one who understands the correct usage and the risks). No provision has been made for a secondary safety to be fitted to the bag. Anything else we could add to the list? Link to comment Share on other sites More sharing options...
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