Horizontal Rope-Access Lines?

[TeTimothy]

Hi,

 

One of the Venues I work in are looking into implementing an access solution for one of their trusses, Previously a Tallescope was used, but the management have decided they want to stop using it due to the recent HSE hype.

 

The Truss (Prolyte H30V) is about 7m off the floor and about 50cm away from the ceiling.

Their floor is not strong enough to support a genie or cherry-picker etc..

 

Someone came up with the idea of possibly getting someone in to string a steel line from one wall to the other (about 15/20m), and then use the line to traverse back and forth across the truss to focus the lights.

 

I've seen horizontal steel lines used for fall-arrest systems, but was wondering if anyone knew if it was actually possible to use this kind of thing for access, or had come across such a system anywhere?

 

Thanks in advanced,

Tim

[Ynot]

I can't say for certain but I seriously doubt this would in any way be feasible.

 

For this to work you'd need the line to be pretty much totally rigid, so that anyone in a harness/whatever traversing the line was at the same height all the way along.

To get a steel line taut enough to keep it anywhere near this rigid state would require enormous tension, even if it were feasible. I'd say that even with it being taut enough, there would likely be enough give in the line to create a dip in the midle of the line so as to put the focus-op a foot or three lower than at the ends.

 

I'd say this was a no-brainer (though if anyone knows it CAN be done, please educate me...)

[andy_s]

Why does the venue management want to stop using the tallescope? it seems to me to be a suitable form of access equipment if powered access is not a viable alternative.

 

What they must do in order to stay on the right side of the HSE is to establish a healthy and safe regime that ensures that the 'scope is not moved while someone is occupying the basket at the top.

 

I have seen a catenary wire installed to support the weight of a human being on a trapeze (many years ago, in a converted church. very massive stone walls to take the load on the catenary. Circus marches to a different drum...), and the deflection is indeed as Tony expects.

 

(edited to add - this wasn't a show I was working on, and I couldn't vouch for this as a sensible practice..... however, neither the church nor the trapeze fell down......)

[TeTimothy]

Thanks for the replies guys,

 

I can't say for certain but I seriously doubt this would in any way be feasible.

...

I'd say that even with it being taut enough, there would likely be enough give in the line to create a dip in the middle

 

That was my first thought, and as you say it would be incredibly un-practical when actually trying to focus in the centre, not to mention the potential swaying etc. - Its just not a sensible idea!!

I guess you might be able to support the line at regular intervals along its length, but then you have to deal with negotiating past the anchors.

 

Why does the venue management want to stop using the tallescope? it seems to me to be a suitable form of access equipment if powered access is not a viable alternative.

What they must do in order to stay on the right side of the HSE is to establish a healthy and safe regime that ensures that the 'scope is not moved while someone is occupying the basket at the top.

 

To be honest I'm not sure exactly why they want it to stop being used, from what I gather it was a last-minute decision before the boss went on holiday he banned the use of the 'sope and he wanted some alternative access solutions to be looked into. But personally I agree with you, as it looks to me as it's the most sensible option - Just someone suggested this and as I said I have not seen it before, so just wondered if anyone else out there may have come across a system similar. I'm sure there will be discussions first thing on Monday on his return!!

[mac.calder]

If your venue is so against a tallescope, instead of wire, look at getting a bosuns track with a horizontal line to act as a safety. That said... In the event of something going "wrong" in the air, how will you enact a rescue? Harness work has an entirely new range of of issues that standard work platforms don't.

[Tomo]

If the truss is always at that height and location, then a track with fixed bosun's chair would probably work well.

 

Seen those used on ships quite a lot - access to the end of the track then get into the chair from a small platform there. A rope system (much like tab track) is used to traverse the space.

(It's usually for front of house - this system is much safer than a ladder on a moving ship)

 

Rescue is generally back to the loading platform by pulling the chair back in on the rope, though you'll need good access to that platform of course.

[paulears]

Forgive me - but this is exactly what I suspect many people thought would happen with the publicity and interpretations of the HSE position. Tallescopes being abandoned in favour of far more potentially dangerous practices.

 

I used an old rope rigged bosun's chair and it was the scariest focus session I ever did! The track is much better, but half an hour in the harness is far more uncomfortable and tiring than even repetitive climbing up and down.

[TeTimothy]

Thanks again Guys,

 

Bosun's chair on a track sounds like it might be a solution. Rescue should not be too much of a problem, as all the Techs are Rescue trained we would just need to sort out rescue plan and do some specific re-training on it with everyone.

Any ideas on possible manufacturers/companies who may install such a system? I've done a little searching, but cant seem to find much relevant info.

 

All that said, I'm hoping we will just be able to make the case to continue with the use of the 'scope and put in-place some work regimes for it.

[kerry davies]

With Paul all the way. Wires and bosuns chairs are not a good idea and having a modicum of thought BEFORE issuing inappropriate knee-jerk bans might be an idea.

 

Why is current UK management so daft as to prohibit something vital to operation and then expect staff to come up with a retrospective fix? This is the kind of lazy lack of thought that creates the Myth Of The Month cartoons. All that needs to happen is to use the damn thing correctly, rather than the blame culture automatically using the HSE as an excuse.

Rant over. How much do they want for the tallie?

[Jivemaster]

Do yourself a simple calculation of the load you expect the cable to support. As the sag gets less then the tensoin approaches infinity and the wire breaks or the walls cave in.

 

I'd also wonder about the "rescue training" of a crew provided by an establishment with this attitude to safety.

 

The simple and compliant method is to use the tallie within the regs and ACOP and HSE's current advice. After that a good solution would be to put in a floor that will stand a MEWP, with a parking space. Alternatively arrange for an access walkway to be architecturally installed between each truss and within safe working range of each fitting.

[karl]

With Paul all the way. Wires and bosuns chairs are not a good idea and having a modicum of thought BEFORE issuing inappropriate knee-jerk bans might be an idea.

 

Why is current UK management so daft as to prohibit something vital to operation and then expect staff to come up with a retrospective fix? This is the kind of lazy lack of thought that creates the Myth Of The Month cartoons. All that needs to happen is to use the damn thing correctly, rather than the blame culture automatically using the HSE as an excuse.

Rant over. How much do they want for the tallie?

The problem is that people won't use tallescopes properly because it's too much like hard work so management feel the only safe option is to ban them completely. This suddenly leaves a huge problem regarding access and people start getting creative with potentially lethal consequences. I suspect we'll be hearing of numerous people maimed and injured as a result of using Heath Robinson approaches to replacing their tallescopes. Step ladders on a trolley any one?

[kerry davies]

Oh Karl, do keep up..... the mad hippy have beat you to it...

http://www.blue-room.org.uk/index.php?show...40865&st=50 See post #56 which clearly shows that those drilling holes in their own heads are not alone.

[TeTimothy]

This suddenly leaves a huge problem regarding access and people start getting creative with potentially lethal consequences. I suspect we'll be hearing of numerous people maimed and injured as a result of using Heath Robinson approaches to replacing their tallescopes.

 

Just to clarify, I wasn't intending on installing some Heath-Robinson system and was just interested as to whether anyone knew of a system that did that kind of thing, Which could be properly Installed!!

 

Anyways, Seriously after a heated debate with the management this morning you will all be pleased to know that it has been agreed that we can continue to use the 'scope after a set of working practices have been written up.

 

Thanks for your help

[dynamo_ozz]

This suddenly leaves a huge problem regarding access and people start getting creative with potentially lethal consequences. I suspect we'll be hearing of numerous people maimed and injured as a result of using Heath Robinson approaches to replacing their tallescopes.

 

Just to clarify, I wasn't intending on installing some Heath-Robinson system and was just interested as to whether anyone knew of a system that did that kind of thing, Which could be properly Installed!!

 

Anyways, Seriously after a heated debate with the management this morning you will all be pleased to know that it has been agreed that we can continue to use the 'scope after a set of working practices have been written up.

 

Thanks for your help

 

It's becoming alarming that venues started to consider banning the 'scope and thinking of installing much riskier systems. The scope is the least dangerous piece of access equipment compared to any horizontal fall arrest systems as long as; a) It's used in line with manufacturer's recommendations, b)used on a flat, levelled surface, c) as with any other work equipment, regulary inspected for safety. I think this is the second or third time I am hearing let's ban the tallerscope approach this week.

 

Keep us updated here TeTimothy.

[andy_s]

and of course the tallescope can be deployed on non - flat unlevelled surfaces by using the adjustable legs and incorporated spirit level to ensure correct set-up.