load bearing certificates?

[top-cat]

The question over whether a truss is a lifting accessory is a contentious one that has been asked many times and nobody is really able to clarify it. My stance is that yes it is, you use it to lift quantities of lights, it doesn't have it's own contribution to the show.

 

Your truss is something which stands between you and tons of movers crashing to the floor. If you are not treating it as a lifting accessory then I wonder what you are treating it as... Because frankly if it's not a lifting accessory, your lights should be directly attached to something which is.

 

Also mother grid truss is not classed as part of the structure, it's also lifting equipment and lifting accessories. It is a demountable addition to the building for the purpose of lifting. That can not be considered an integral part of the structure to work around legislation.

[paulears]

I've been talking to some engineers who inspect, test and certificate BIG equipment used in industrial and offshore environments. Their attitude is to ignore existing paperwork and inspect properly and comprehensively. The safety documentation then covers everything. They found the notion of excluding certain items from the inspection ridiculous. They've just done my poorly maintained venue's kit. Not just the usual theatre stuff but other equipment too, identified by the insurance company. There is mention of work required to timber safety handrails in the grid, and in one non theatre area, comment on a steel wire rope that is cutting through a nearby timber strut. Their attitude is that everything they see or identify gets listed.

 

Here we seem to be attempting to include or exclude things. Slotting equipment into a column on a spreadsheet under it's controlling or prosecuting act of parliament seems to perhaps be the wrong way of doing it.

 

Getting the manufacturers spec on a bit of truss, and then loading up to almost that limit is within the law, but is it sensible or responsible? The company that did my truss did not know the specs, but they knew the material, they inspected the welds and decided all was well based on what they do.

 

During the inspection, I was a little worried about one of our bars on stage that is always loaded cradle full+1, in the loading slot position. 250Kg full. It worried me it was always like this. It turns out that all the pulleys and hardware are exactly the same as the sets rated at 350Kg, the only difference being cradle size, and again they were perfectly happy. I can't tell the difference in the pulleys up top. They look a little different, but aren't. I asked why we have a sign saying 250kg? The answer was simple, "that's what you asked for". We have two motorised LX bars, which are labelled as 250Kg - turns out they're actually ex-big london opera venue, and are actually 1000Kg rated, but when asked for the likely load we would have I said 250, and they just nodded.

 

 

Maybe were over analysing all this? The OP wanted a load bearing certificate, so get the right people to produce one, and sleep easy!

[dbuckley]

This comes back to the engineers modus operandi that we've observed before.

 

Engineer arrives, takes a quick look, thinks "that's good for at least X kg". Asks "what do you to hang off that thang?" And if the answer is a fraction of X, then the paper is signed without much ado. Get somewhere near half X and the fine tooth comb comes out.

[top-cat]

I've been talking to some engineers who inspect, test and certificate BIG equipment used in industrial and offshore environments.

 

Off topic, and I'm not saying you do, but unfortunately some people do sometimes have the attitude that using big offshore or tower crane lifting inspectors is better than using theatrical inspectors, because bigger kit means you are better right? Sometimes the result can be that they don't understand the unique way in which we do things in the entertainment industry, and things which are signed off as OK are not always so. It can be useful to have a periodic inspection at your theatre performed by a company like PSI or ISS, who are more experienced in theatre flying, as they may spot hazards that are not apparent to people who solely do lifting. They will also be able to carry out quick fixes on equipment that general lifting inspectors are not familiar with.

 

Their attitude is to ignore existing paperwork and inspect properly and comprehensively. The safety documentation then covers everything. They found the notion of excluding certain items from the inspection ridiculous. They've just done my poorly maintained venue's kit. Not just the usual theatre stuff but other equipment too, identified by the insurance company. There is mention of work required to timber safety handrails in the grid, and in one non theatre area, comment on a steel wire rope that is cutting through a nearby timber strut. Their attitude is that everything they see or identify gets listed.

 

To walk in and treat it as a new project is quite common, and inspecting everything is a concept I think is good. You yourself have said (recently) "install it as a fixed bar and then you don't have to have it inspected under LOLER" , but is that the right attitude? Should we be designing things to engineer out the need for inspection? Or is the need for inspection still there, just not the legislation to support it? I have inspected many freestanding structures which do not necessarily require an annual inspection by law, but the custodians of these structures feel that, since it is a demountable structure to support loads over people, it should be inspected, legislation or not.

 

You will find the attitude is shared by the good theatre inspectors. The benefit of using the theatrical inspectors is they can often make recommendations based on industry knowledge, and recommend suitable products produced to fix such issues. I am not trying to make a sale for anyone here, I do think it's a genuinely good concept to use inspections companies who are familiar to the particular industry in which you are working. I went into a theatre who had had their counterweight bars load tested to their full capacity, and given nice little stickers to say they were all fit to take 350kg. Was any comment made about the fact that many had slack lines on them, where the rope was so loose it could easily hop off the pulley and sit on the bolts? No. Was any comment made on 2 of the hemp lines being extremely worn out and in dire need of replacement? No. And was any comment made about the fact that there was nothing preventing the travel of the fly bars into the sprinkler system? No. (Flymen - "that's just how it is here, we just have to get somebody to watch out from the grid"). It took us a few hours to tighten the slack lines, measure up for new hemps, and add a simple hard limit to prevent the bars being driven into the sprinkler system. But the previous few years of 'industrial' testing had not considered any of these things an issue.

 

Getting the manufacturers spec on a bit of truss, and then loading up to almost that limit is within the law, but is it sensible or responsible? The company that did my truss did not know the specs, but they knew the material, they inspected the welds and decided all was well based on what they do.

 

It depends what you are doing. It is an often misunderstood point, but "LOAD TESTING" and "THOROUGH INSPECTIONS" are different things. A thorough inspection will look at the truss in detail, check the tubes for signs of wear and damage, inspect the welds and the connections... and ultimately if there is nothing on that piece of truss to suggest that it's any less capable of supporting a load than it was when it came off the production line, it can be passed. Load testing is the act of putting test weight onto an item (either through actual weights - IE stage weights; or using something like a pull tester, which is basically a hydraulic ram on a hand screw that can pull away at eyebolts etc with little human effort) to 'prove' it is still capable. Considering that most truss will have at least 4:1 safety factor, loading it to 125% of it's SWL should still be only 30% of it's MBS, and so not particularly irresponsible. In controlled conditions you can test full on structures, last year I ran a 100 ton load test on a roof grid, since the previous rating had been made by calculation only, and an incoming production was insisting that it's rated capacity be proven.

 

Maybe were over analysing all this? The OP wanted a load bearing certificate, so get the right people to produce one, and sleep easy!

 

The only unfortunate thing is that engineers to come and inspect and produce documentation can be expensive. You will be looking at 400 GBP per day per engineer (and it frequently takes 2), plus the administrative fees and any costs for test equipment, which is usually hired from the local HSS, because driving a van full of a test weight is a false economy.

 

For the OP's purposes, I should imagine that flashing the certificates provided with the truss and with the deck will be adequate to get the health and safety man aroused. But topics like this can be good for theatre custodians, indeed like yourself, in getting guidance for what they need to be doing in terms of inspections, as it is still tetchy ground where anything that doesn't actually move up and down with stuff on it can prove to be uncharted territory.

[Seano]

Maybe were over analysing all this? The OP wanted a load bearing certificate, so get the right people to produce one, and sleep easy!

 

Except that the term "load bearing certificate" has no specific meaning and it doesn't seem to have been established what the person asking for one actually wants. (Or indeed whether they even know what they want.) The assumption underlying the last few posts, that "load bearing certificate" means evidence of a thorough examination, is just that - an assumption.

 

I have inspected many freestanding structures which do not necessarily require an annual inspection by law, but the custodians of these structures feel that, since it is a demountable structure to support loads over people, it should be inspected, legislation or not.

..last year I ran a 100 ton load test on a roof grid, since the previous rating had been made by calculation only, and an incoming production was insisting that it's rated capacity be proven.

 

You say this kind of thing a lot, but you're always vague about the details and of course you post anonymously. I, for one, am inclined to take it with a big pinch of salt.

[Bobbsy]

Frankly, to me this sounds like the typical game of liability shifting in case something goes drastically wrong. The organisers want to show they did due diligence about the safety aspects so they ask you to, in effect, guarantee that everything is safe with a "load bearing certificate". You, of course, can't issue such a certificate (neither could I) so you have to get somebody (a structural engineer or maybe the manufacturer of the truss and deck system) to give you an okay...and so on. This is a game for lawyers. Obviously I can't know but I'd be willing to bet your organisers would accept any bit of paper as long as it shifts any blame off them.

 

However, more important is to find out if the system IS safe and what environmental conditions the safety is judged for. Will your truss and marquee stand up in 40mph winds? 50mph? That sort of thing. You need only see some of the horrific videos of what can happen when temporary outdoor structures are badly installed or struck by bad weather.

 

Where does this leave you? I think you have two interconnected issues. First, you need somebody "qualified" to sign off on your plans the implementation of the plans just for the legal side. Second, and for me more important, you need that person to actually have the skills to genuinely be able to judge the safety.

 

...which is all my roundabout way of agreeing with Paulears that you need to find somebody with the right skills and experience to A) judge the safety and, B) give you a piece of paper with their professional opinion.

[Seano]

The organisers want to show they did due diligence about the safety aspects so they ask you to, in effect, guarantee that everything is safe with a "load bearing certificate". You, of course, can't issue such a certificate (neither could I) so you have to get somebody (a structural engineer or maybe the manufacturer of the truss and deck system) to give you an okay...and so on.

 

Well, again - that may depend on what is meant by the term.

 

Assuming the OP is competent to build the thing and all is well, he certainly should be able to give the event organiser a written sign-off sheet/certificate/whatever.

 

That's one of several things it occurs to me may be meant by "load bearing certificate", and essentially it's just a scrap of paper to say "I [insert name] have built this in accordance with manufacturers instructions and industry 'best practice', as of [insert date/time] the structure is complete and ready for use."

[indyld]

That's one of several things it occurs to me may be meant by "load bearing certificate", ...

 

Every time I read the title, a stiff piece of cardboard springs to mind. Maybe even corrugated, due to the truss-like structure. :-)

 

(Yes, I do spend the weekends helping my daughter build load bearing structures using drinking straws and rolled up newspaper tubing. "Oi, who's had all the Sellotape again?")

[Bobbsy]

Well, again - that may depend on what is meant by the term.

 

Assuming the OP is competent to build the thing and all is well, he certainly should be able to give the event organiser a written sign-off sheet/certificate/whatever.

 

That's one of several things it occurs to me may be meant by "load bearing certificate", and essentially it's just a scrap of paper to say "I [insert name] have built this in accordance with manufacturers instructions and industry 'best practice', as of [insert date/time] the structure is complete and ready for use."

 

To a certain extent I agree but this is where I get all cynical.

 

From my days working on TV OBs and satellite uplinks I recall that, all too often, event organisers have no idea what they mean either but have been told by "somebody" that they need a load certificate/risk assessment/acceptance of liability/promise of first born child or whatever. All too often, the person asking doesn't know exactly what it is they're asking for either so anything provided will likely be accepted.

 

It's for that reason I suggest that the more important issue is to actually be sure everything IS properly specced and properly installed. I'm the first to admit that my rigging knowledge is near nil but, at least for me, there are enough grey areas in the description to make me unsure as to whether it's as simple as "installed to the manufacturers instructions and best practice" or not--certainly moving outdoors introduces a whole slew of extra variables. For example, I notice mention of a marquee. Is the marquee in any way attached to or supported by the truss? If so, it gets into all sorts of silliness about wind loadings and so on. Or, how solid is the ground the truss system is being erected on? What works inside on a concrete floor might be less safe on loose soil on a rainy weekend.

 

I don't want to be one of the "if you have ask don't do it" mob but, at the same time, outdoor rigging is something I'd really want to get right and, if it takes paying an expert to vet and sign off on things, I'm paranoid enough that I'd do it.

[top-cat]

You say this kind of thing a lot, but you're always vague about the details and of course you post anonymously. I, for one, am inclined to take it with a big pinch of salt.

 

Feel free to. I value my clients confidentiality (and the fact that if they want to publicise these things they will do via their own marketing departments) higher than I value your custom for which there has thus far not been any. Hope that's ok for you.

 

The service that I or the company I represent has Been elected to provide involves inspection, testing, certification of equipment. It does not involve writing up about them on the web, and I would not want to compromise my relationships with anyone by writing it up In a manner they would not be happy with. I would rather let them write it up themselves. If any such work is written up by a client for a case study or TPI article or whatever I will be happy to link to it.

[Roderick]

From my days working on TV OBs and satellite uplinks I recall that, all too often, event organisers have no idea what they mean either but have been told by "somebody" that they need a load certificate/risk assessment/acceptance of liability/promise of first born child or whatever. All too often, the person asking doesn't know exactly what it is they're asking for either so anything provided will likely be accepted.

And that is the real underlying problem, utter absence of basic knowledge.

Most of my current work is in the corporate event sector and there is a definite decline in the recognition of qualifications. Too often I am finding that event organisers omit a technical or production manager and leave it to the suppliers to 'sort it out amongst themselves'. And that is where these sort of issues come from. Somebody in the office pipes up and insists that the get a 'insert any technical term' certificate because that's what they had at the last job - for some reason.

And when they then get a piece of paper, everyone feels warm and fuzzy because they have looked after the safety of the job. Never mind that the piece of paper actually had no bearing on the event, the structure or service provided.

 

Recently I was working on an event and when I questioned why the LED screen provider came from 900km away the straight faced answer was that this company had the highest SEO rating. I instantly doubled my fee for the job because I knew it was going to be very painful. And it was.

And now we have arrived at the next level of incompetence where even the suppliers aren't quite sure what the acceptable level of certification, and therefore suitability, is for the services they provide. People buy 'pop-up' marquees at their local hardware store and assume that they'll be OK to use on a job. Wind loading? Counter weights? Who needs them!

And when in trouble, just whip out your 'smart' phone (what a contradiction in terms that is!) and Google your way to a solution.

 

Very soon somebody will die or be seriously injured, maybe that is what is needed to wake-up people.

</rant over - for now>

[top-cat]

Completely agree with all the above in terms of certification, event organisers don't know what they're looking for, all they know is that you need 'a ticket'. I once left my forklift license in the wrong bag and went to a job without one, nevermind, a cherry picker ticket works just as well, they don't know the difference!!

 

But it's the same as the safety people. Work at height without a harness? Dangerous. Work at height with a harness? Safe. What you're stood on, what you're clipped to, what the risks are... all utterly irrelevant. They just 'know' if you are wearing a harness it is all good and if you are not then you are certainly unquestionably going to die.

 

As for somebody dying 'very soon', I do believe they already have, on a number of occasions. All that seems to happen is events are even more determined to hire as many idiot health and safety advisors/consultants/experts/officers/etc to demand pointless tickets and unnecessary PPE as frequently as possible!!

[paulears]

I've actually got sympathy for the organisers and bosses. The legislation, and guidance is now so confusing and misunderstood that you can't blame them for employing an 'expert', with H&S as their primary role, to at least attempt to ensure compliance and have a safer workplace. As we've often commented upon, common sense is no guarantee of 100% compliance. Over zealous and restrictive H&S practices make work difficult, but reduce the risk in most cases. The fact they're frequently not very good systems to work with just has to be lived with. It might even be the case that some members could make a better living BEING the H&S person, as they actually understand how it should be - but it would be a horrible job, and you'd be Billy No Mates. These H&S people we find annoying know they are responsible, so I can never blame them for not taking the risk, when they don't understand it.

 

If they have a piece of paper that says something is safe (but don't understand what it means) it keeps them happy. A certificate that states an item can take a specific load is quite a sensible idea. In laymans terms, a "Load bearing certificate" is a perfectly good example of what they want, and any competent engineer will know and understand what they want and produce one, and send the invoice. I doubt any will take the mickey about the clients ability in the terminology department. After all, isn't it the safety version of the client who asks for power cans, Freshnells and go-boes?

 

Sometimes we take ourselves a bit too seriously, and don't make allowances for people with less knowledge. The people at the top do not have to know everything, that's why they employ us!(and we employ other people who know the specifics).

[top-cat]

The problem is that the "Health and Safety Experts" hold the generic qualification for health and safety, but no qualification for the subject matter in which they are consulting.

 

So you have "health and safety experts" telling riggers that trusses need safeties, or that the diagonals in the truss need to form a continuous pattern in the truss; and make a huge palava about it all, based on their very limited knowledge of rigging. And rather than say "OK, you're a rigger, so I'm asking you to explain this", they enforce their very basic knowledge onto people with extensive knowledge with no option to budge.This is my problem with them. In their quest for a safer world, they insist on telling every department on site how to do their job properly. To be a health and safety man you do a 1 week course, and that seems to qualify you as more knowledgeable in every department on site, than the HODs of those departments who have EACH been doing the job over a decade.

[the kid]

I think you do have a brush there with a bit of tar on it.

 

Having worked with a couple of different H&S guys the ones I have delt with except for one have been very open and questioning, and accepting of "our" rules if we can just provide the reasons why it should be like b and not a.