Safety guidelines/training for use of portable trussing

[parky58]

Hi all,

 

this is my first venture away from sound and lighting discussions. I hope there are some experts who can point me in the right direction.

 

We have just purchased a pair of mobiltech stands (4.1M) and 10M of trussing to use to hang lights and perhaps a couple of speakers at indoor and outdoor gigs. We erected them this afternoon and I am very impressed.I am not concerned with loading as we will be well within the loading parameters of the equipment. I had intended to speak to the technical people at mobiltech about these points, but it is now four o clock in the afternoon leading into a bank holiday weekend, so rather than wait till tuesday or scour for info on t'internet I would appreciate a few pointers. Here goes;-

 

Is there a formal code of practice for use of this equipment?

 

Is there a training course which will satisfy H&S and insurance etc?

 

The truss came with nuts and bolts to join the lengths together - could we use pins and R clips?

 

The end plates on the trusses have 3 holes. Is it advisable/ a requirement to also bolt the lengths together?

 

Is it a requirement to guy the truss indoors/outdoors?

 

I know there will be threads which deal with at least some of these points in the BR but I would appreciate if a kind soul could answer the above, then I can change my thoughts to something else for the rest of the weekend.

 

Thanks in anticipation,

 

Steve

[Simon Lewis]

Steve,

 

I would suggest:

 

Is there a formal code of practice for use of this equipment?

 

Not as such - but as you are in business the activity does come under general H&S and specifically LOLER (at least my lifting inspector counts my wind up Manfrottos as 'lifting equipment'), PUWER etc.. There is a requirement to demonstrate competence, and to work within the manufacturers guidelines.

 

Is there a training course which will satisfy H&S and insurance etc?

 

There's a national rigging certificate - but that's somewhat OTT for a pair of wind up stands. A basic rigging / Work at Height awareness course would be useful though. H&S (and your insurers?) want to see competence - a mix of (mentored) experience, knowledge, training and understanding.

 

The truss came with nuts and bolts to join the lengths together - could we use pins and R clips?

 

If the manufacturer says so, then yes. But it looks like a tube coupler and bolt system.

 

The end plates on the trusses have 3 holes. Is it advisable/ a requirement to also bolt the lengths together?

 

If the manufacturer says so, then yes (you can see where this is going...!).

 

Is it a requirement to guy the truss indoors/outdoors?

 

Here's where the problems start... 10m of truss on two 4.1m wind up stands indoors may well be stable and never fall over, but if it's the stuff I think it is, the truss has an UDL of 148kg. You state that you'll be well within the loading, but a knocked stand or uneven winching can change weight distribution rather quickly. It's a big piece of truss to be winching up.

 

Personally, I would be slightly uncomfortable using such a system outdoors. Factors such as getting the feet level, ground stability & load distribution (the feet are pretty small) and most importantly use of a goal post (apply a K factor of 2) with the attendant problems of windage etc. means lots of potential problems. Of course, you may never experience any issues, but as a system morphs from a simple 6' DJ goalpost to something bigger and heavier, at some point you have to apply the same rules as you would with a outdoor stage system. Guying introduces additional problems - not least the extra down force upon the stands.

 

At the very least I would seek guidance from the stand & truss manufacturer concerning the conditions their products are manufactured for.

 

Just my 2p...

 

Simon

[paulears]

It does strike me that two support points on 10m of truss is going to be pushing it. The typical style of truss that can be supported on wind-ups isn't the heaviest duty, and if it uses bolt together plate coupling, then it's going to sag like mad as the bolt plates bend. Some types are rigid enough to cope, but once you've got a bit of weight up there, it'll probably look like a roller coaster.

 

Stopping the damn thing falling over at 4m would worry the hell out of me. using it on soft ground even more so!

[parky58]

Thanks Simon and Paul for your advice. I will certainly read up on the H&S regs identified. I have done a working at heights course albeit 5 years ago. I certainly won't be needing the mast climbing aspects though.

 

It seems obvious I need to speak to the manufacurer. The system is Mobilteck SpTek400 and pad250 trussing which was sold as a package. We are only likley to load with 12X PAR64 or 5 X Spectres so loading less than 40Kg. Id does use tube couplers and appears to be able to use bolts through the plate as well. I will of course contact Mobiltech next week.

 

I am, by nature a very safety concious person so will certainly not push things to the limit. I appreciate your considerations about the height, guy downforce and correction factor etc.

 

Thanks again chaps