Are you rigging safely?

[Thirdtap]

'Lo

This comes from several conversations I have had with regards to Safe Working Loads. Some lighting fly bars and tripod stands I have used over the years used to get loaded up and used regularly. These didn't have stated SWL on most items, now one venue I have worked in they have had the units tested and a SWL has been posted. Once the tech worked out the weights of the lighting stock the bar is only ever loaded up to the limit and has no where as many lanterns on it now. The same has happened to tripod stands. Some old Strand stands were regularly used with T bars and a few lights when in fact this was way over their intended load.

I know this is covered by LOLER and PUWER but from what I can make out most of the industry including myself seem to be in the dark about what to do.

[Ike]

Not quite sure I have got the right end of the stick but...

 

If I am designing I will look up the mass of each lantern, splitter etc that I use. I will then add a 'bit' on for cable, the amount I add on tends to be an educated guess however I will occasionly work it out. I will than check this against the SWL of the bar.

 

If I am rigging and there is no SWL on equipment I take a common sense aproach and estimate what I can rig. I would not take this approach when dealing with big bits of truss, chain hoists etc.

 

I think the most important thing here is experience and knowing your own limits. I have gone slightly over a SWL on a couple of occasions however I wouldn't suggest others do the same. SWL's are there for a reason, not only do you risk legal action and invalidate many insurance policies you also risk causing you or others serious injury or death.

[Andrew C]

Having in the past folded two sections of a three section Manfrotto in half, I am very much more careful now. There wasn't much weight on the stand, but we (my colleague) had the bright idea "to move it a couple of feet" with it fully extended. It was all going well until we got it a few degrees off vertical.

;)

[sam.henderson]

If you don't know how to do something then research it!!

 

Just cous' youy don't know doesn't mean you can't do it full stop, go check the weights do your sums and off you go. You would be foolish to ignore Safety Guidelines they are after all there for a reason (even if we do sometimes think they are just there to make your bad day even more akward)!

 

Sam

[gareth]

The only safe and permissable way to do it is to know that the supporting structure (be it a stand, tower, flying bar, truss, whatever) is rated sufficiently to take the weight that you're about to put on it. If you don't know the weight of the equipment you're going to rig, there are many ways to find out. LD Calculator Lite (download it here) is a very useful tool for calculating loads (among other things), and there are various sources of reference which can be used to determine the individual weights of pieces of equipment - manufacturers' web sites and data sheets are a good one, and hire catalogues from companies such as Stage Electrics and White Light will usually have that kind of information for the equipment in their hire stock.

 

Rigging something that's too heavy, and then using "but I didn't know how much it weighed" as an excuse when you've just bent a piece of Trilite in half by overloading it, is NOT an acceptable way of working in these H&S-enlightened times.

[Ike]

Don't forget to add the weight of the hook clams and secondary suspension etc. I know it won't add up to much but you should still take account of it.

[Jivemaster]

Reading Land Rover World recently I saw an ad among the winches for a tested electronic load cell -- to indicate the load applied when playing in the mud. Methought that ought to have a rigging application. After all its not only landrovers that hang from winches on wires.

[gareth]

Reading Land Rover World recently I saw an ad among the winches for a tested electronic load cell -- to indicate the load applied when playing in the mud. Methought that ought to have a rigging application.

It does. Load cells can be, and are, used to monitor the loads being imposed on rigging points.

[Brian]

Reading Land Rover World recently I saw an ad among the winches for a tested electronic load cell -- to indicate the load applied when playing in the mud. Methought that ought to have a rigging application.

I have a friend who weighs aircraft for a living, now that is serious stuff. You really do not want to drop a helicopter as it hangs on a single point during testing or even more expensive, have a 777 slip off its jacks.

[James]

I've been guilty of a number of sins here.

 

One of the worst cases was a powerdrive Ref 44 stand (40Kg SWL)

 

Loaded up with

 

2 1K Sill 15 (21.9Kg ea)

1 Patt 252 (16.5Kg)

2 Patt 23 (3.9Kg ea)

1 Patt 750 (4.6Kg ea)

 

gives me 72.7 Kg + Cables Grelcos etc.etc.etc...

 

However this was a stand in an inaccessable location unextended (the bar was at the minimum height and it wasn't the only means of support for the bar.

 

James

[Pete McCrea]

As fair as I now know you should only load a point to it's SWL. And if there is an LX Bar then this should have a SWL noted for it. I think that if you were rigging something and the bar didn't have an SWL, it then fell and the HSE were called in then you'd be in the brown and sticky for using an unrated peice of equipment.

 

I'm helping to put in an install next weekend for a new venue in Gloucestershire- 36 lodestars each with loadcells in the shackle of the point. As house riggers we'll be able to tell you exactly the weight on each point, as well as the loaction of the hoist on the chain in terms of links.

[Guest lightnix]

...the bar was at the minimum height...

Interesting thought just struck me there. Does the quoted SWL of a Powerdrive stand (not sure what model) refer to it's "down" or extended position. How does the SWL vary in relation to how tightly the screws have been done up. Is there a recommended tightness for the screws and if so, is it time to invest in a torque wrench ?

 

I'm not being flippant here, honest.

 

What about Manfrottos ? Surely the SWL of any extending / wind up stand is greater when the stand is not extended / wound up.

 

Can somebody competent set me right here ?

 

Maybe there should have been a response saying "Draw the plan and leave the riggers / flymen to make sure it's safe." Seriously, that's how it works in some parts of the business. After all, LDs design lighting systems. Riggers / flymen design the means to hang them safely.

 

If you don't know how to do something then research it

Or get someone who has already researched it and maybe has more experience in the matter to do it for you. Then you have the opportunity to learn from them as they do it (and probably a lot faster than you or I will, too).

[Thirdtap]

The Stage newspaper headlines

 

It looks like a the attitude of people here is good with regards to rigging, but from conversations with people in the industry they aren't given the time or information to rig safely sometimes. One person I spoke to he had to recently rig video, sound and lighting on a section of truss between two wind up stands. He did explain to the production manager his concerns about overloading the stands and was told that 'it will be ok we have done it before'. This does seem to be an attitude in some parts of the industry. How long or what will it take until people deal with rigging as they do with PAT testing?

[Ellis]

If someone more competent than me has determined a safe working load and certified it, who am I to question them (I can, however raise concerns about possible changes after they certified it).

 

Provided I follow their recommendations and all other guidelines, I am meeting my obligations under the duty of care.

 

It is important to keep all certificates to ensure that:

 

A: You can verify that someone else (presumably competent) has certified the system within accepted timescales.

 

B: The safety of the system is not obviously compromised (User Inspection - keep a diary)

 

C: You can prove it in the event of a failure.

[Chris Higgs]

With my "Slick" hat on, since it was mentioned in a post - please do not use 'wind up' stands intended for lanterns for supporting Total Fabs/Slick trusses without properly assessing the risks and taking appropriate action.

I can't speak for anyone else's trusses, although I don't see the difference.

Even if the stand is strong enough (which it may be in terms of vertical load bearing capacity indoors) it won't be designed for something as inherently unstable as a truss and load which will probably weigh upwards of 50kgs and span as much as 10m. Lights get knocked, moved, people walk into stands, etc.etc..

The stability is compromised and collapse should be guarded against with appropriate secondary means of support or redundancy. Not a loadstrap around the nearest thing above the most accessible ceiling tile..............

I have seen some lighting (as opposed to rigging) companies use 'wind ups' to get the truss to height BUT then install ground support with returns/outriggers/kentledge before removing the lighting stands.

I often used Genie Superlifts for the lifting, but added appropriately stable (truss) towers to support the truss long term.

What would the loss adjuster say about using lighting stands when it all collapses?

What would the lighting stand manufacturer say?

I am a bit concerned about some of the 'brackets' you can get that seem to ask you to clamp your truss (apex down, irrespective of engineering design?) to a TV spigot so you can use a lighting stand.

Just a thought.....

 

Chris Higgs (Total Fabrications/Slick Ltd)