Event Safety and Temporary Stage Design

Following the recent news of several stage and event structure collapses, On Stage Lighting looks at where we have come from as a fledgling industry and where we might look for a path in the future.


Stage Roof Collapse

This last month or so, it’s been a regular event: The reporting of a temporary structure failure at a show, leading to serious injury and loss of life. In recent years this kind of news is no longer unheard of, either during a build or a show, something in a roof support or rigging system fails and sets off a chain of events that is putting people in danger.

There has been, and will be, a lot of speculation about specific recent failures, much of it temporal conjecture and even more of it political wriggling, blame and avoidance. Once the bereaved have been comforted, scapegoats cited (like the Weather Gods), legal proceedings done and lip service paid to future event safety, there is the horrific possibility that the “show will go on.”

My hope is that there will be some actual lessons learned and disseminated throughout the industry – but how?

We Are Toddlers

The live event business has grown up fast, now calling ourselves an “industry”. Not long ago it was nothing more than a collection of individuals putting on shows with whatever they could hack together. Look around you at the tools and systems we have now, many of them nicked from a wide range of unrelated industries, construction, lifting, cargo, shipping, military, telecoms, rescue – the list goes on.

Not so long ago, we were using electric hoists in vibrant colours with the decals “upside down”, the casings sprayed black to make them less obtrusive in a show environment. Spansets only came in a range of colours based on their working load. Now they come in black and are sold by sales reps that actually know which way is “out”. We design structures using things we already use, added to other things that we already use with some custom fabricated items. And then put a roof covering on it.

We have a short history of finding ways of doing things quickly, cheaply and to satisfy the needs of the show for the short period that it runs.

What we don’t have is a long history of shared design standards and practice. The industry has just started, in relative terms, we have the beginnings of all these things and have come a long way in the last 40 years.

The Institution of Civil Engineers (ICE) was founded nearly 200 years in a London coffee house and continues to provide a platform for the sharing of knowledge, as well as being a qualifying body and promoting the profession. We have PLASA (encompassing ESTA), which produces things such as “ANSI E1.21-2006 – Temporary Ground-Supported Overhead Structures Used To Cover Stage Areas and Support Equipment in the Production of Outdoor Entertainment Events”, written by industry professionals and currently under review. It is, however, important to remember that PLASA describes itself as a “pro-active trade association”, which means it rightly represents the interests of it’s members.

On the structures guides front, there is also the “Temporary demountable structures. Guidance on procurement, design and use” from the Advisory Group On Temporary Structures at IStructE (see, another professional body).

This continuing professional body model, like the ICE or IStructE, is surely vital in our future and hopefully still doing great work in 200 years time.

A professional body should be able to collate and disseminate design or implementation failure information, outside of the politics, lobbying or blame investigations, and make recommendations specific to the industry that it understands.

The Show Must Go On

It’s a badge of honour in our business. No matter what, by hook or by crook, the audience will not be disappointed and the show must go on. It’s a great way to galvanise the highly committed individuals in show business, getting the best out of people against the odds. But it leaves a legacy.

The idea that someone would dare to put their head above the trench and say “Stop” isn’t entertained. Stop, it’s dangerous. Stop, this person is too tired. Stop, this needs to be done in a way that costs more time and money. Stop, it’s just not possible. Sometimes, someone needs to have the conviction to walk out on that stage and say “Sorry, 20,000 people. We just need to stop.” I’m not talking about the automation tripping or the show Mac locking up and stopping the show, I mean saying “OK, things might seem fine right now but there is a risk…… And we can’t continue.”

The transient nature of live events is that, unlike a permanent building, it only has to get us to the end of the show – not last 50 years. This leads us to bodge perfectly safe solutions when a smoke machine duct hose goes missing or we need to use a road box as a table but it’s that same culture can lead to holding out and hoping that things will be ok for the next couple of hours. This is obviously not acceptable when it comes to serious stuff like the stability of structures.

Pseudo Safety

Sometimes people like to feel safe, so they do things to make themselves (or someone else) feel better. That might be using some form of under-spec’ed secondary safety bond, or attaching it to a point that is not actually going to take a decent shock load. It could be fitting an anemometer to a PA wing and occasionally checking the Met Office website first thing in the morning.

Say you have a structures guy with your gig. He clears the standing water regularly, keeps an eye on how the rig is loading the roof and generally sorts stuff out with 5 ton ratchet straps. The anemometer spins away on the PA wing, telling somebody that things are “safe” – it’s there reading wind speed after all.

What is the procedure if the wind speed reading gets to a certain point? Does he mention it to Production and what is their response? Is there a system in place to quickly remove the coverings to reduce wind loading? Now the structure is fully loaded with kit, can he even get to the coverings? Are the stage crew briefed on how to do this? Will anyone even entertain the idea that the covers need to come off, despite the thousands of pounds worth of moving lights and other kit that will get soaked by the rain? At what point will someone make the decision to systematically clear the stage area and crowd and stop the show? Who will make that decision? Will anyone actually do it – especially if the weather is not even on site yet?

Without all the following questions answered BEFOREHAND and the system in place, the anemometer is pointless.

I’ve seen many instances of pseudo-safety and box ticking in my career, things that don’t in themselves make life any safer but reassure you or others that something is being done. Luckily, most of the time this pseudo-safety isn’t actually tested.

Design Standards

Safety procedure is about having systems in place and actioning them. But we are also responsible for designing and erecting these structures.

Looking again at engineers in other industries, if you designed or built a structure that flat packed after a few 70 mph gusts that would be the end of your career and rightly so. Being responsible for a permanent structure that couldn’t stand up for it’s lifespan is unthinkable and even then the unthinkable happens, it’s because of a genuinely unforeseen set of parameters that were not understood at the time (like the collapse of the WTC.) These events change design standards for good.

Engineers design things to withstand certain conditions, in some disciplines this might be a weather event that occurs once in one hundred years, or once in five hundred. If you designed a building to withstand a 100 year event, if the building was going to be useful for 100 years then you would assume that such a design standard would be prudent.

Our temporary structures might not be up for more than a weekend. Does this mean that a 1 in 50 year weather event isn’t going to happen in that time? Of course not.

A lot of the catastrophic failures of temporary alloy structures in our business play out as a cascade of events. Something fails and the rest of the system follows. We are using lightweight, portable and demountable components that seem to be nearing their limits as a system without a more fail-safe approach. Let’s not forget that in recent years we are asking so much more of our temporary structures – the average moving light weighs 10x more than a PAR can. In the 70’s if a bit of tarp blew off the meagre scaffolding structure, it wasn’t a big deal. All of a sudden, we are putting more in terms of weight overhead than we have on the deck.

A fail-safe design takes into account the possibility of individual component failure, without jeopardising the rest of the structure as a whole and seeks to avoid further damage or injury. So many entertainment rigging failures have caused additional failures, rather than behaving in rip-stop fashion.
Another design standard that should be considered is the time it takes to avoid injury and loss of life. This is not somehow coming up with a design that is never, under any circumstances, going to become unstable and collapse – that would be uneconomic if not technically impossible.

Given that failures occur, how long can a building remain in an unstable state without complete failure, in order for the occupants to be alerted and evacuated to safety? Back in our world of temporary event structures, time between the initial failure and the catastrophe is unreasonably short at the moment.

The Future?

It is important that us toddlers are grown up enough to realise where our tiny industry is and how far we still have to go, including in areas of safety procedure and design standards. We need to continue to follow any good examples set by more established professions in terms of the sharing of knowledge and qualifying.

We also need to ensure as an industry that we make our own investigations and are realistic about the facts when things go wrong, it would be too easy to go along with the idea that it’s just “one of those things” and walk blindly into the next catastrophe, muttering “The Show must go on..”

Image based on a picture from helixblue on Flickr

4 thoughts on “Event Safety and Temporary Stage Design”

  1. Hey Rob,

    Great article as always. Got a few choice phrases now in large print taped to our control room wall, just a subtle reminded :-P

    Cal

  2. Great article, very interesting read.

    I myself was present at Pukkelpop in Belgium when disaster struck.
    The weather event that took place was indeed such a ‘once in 50 years’ kind of thing (in our region anyways, it was very unreal).

    The structures that failed were a tent, wich collapsed entirely (taking down the stage inside), a huge sunshade construction and a LED screen that was supported by a free standing structure in front of another tent that toppled. All of those structures had been inspected and had passed inspection.

    The severeness of the storm however was more then any of the structures were designed to handle, and what you are stressing in your article, being the lack of actual action when things go bad, is exactly what went wrong.

    Nobody had the guts actually to cut down the covers and other huge wind-catching objects. Nobody was briefed on what to do when the limits of the structures were breached.

    The weird thing is, after the Indiana-incident (and a week before Pukkelpop) I was actually debating with someone I know that rents and builds prolyte stages. He had devised a more ‘mind soothing’ then realistic action plan, being to cut down the sides of the stage when things would get dangerous. How to actually do that however, with a stage height of 10 metres, still remains a big question. I was only at Pukkelpop as a guest, but from what I witnessed the crew was just as helpless and clueless on what to do as the crowd. Luckily, the lack of communication ment that everybody just stayed calm after the storm had passed. There was no huge outburst of panic, wich could have caused a lot more injuries and maybe even deaths.

    What the industry (here in Belgium anyways) seems to have done to act on last summer’s drama’s is improve the communication tot the crowd. In the actual stage building however, I don’t see much change. Things already were rather strict on their own, even though there isn’t really any regulation. (Getting the stages checked by an external firm is not always a requirement, that depends on the wishes of the local fire- and police departements.) Practically, most big festivals in Belgium provided an emergency Public Adress network, that relies on a radio frequency and 100 volt horn systems on their own power unit and they use the Screens next tot the stages to give proactive emergency instructions.

  3. Thanks for your thoughtful and interesting comment Bavo. I recognise your concept of ‘mind soothing’ plans or actions. Perhaps it’s human nature to find comfort easily in making such plans or taking such action, even if it’s actually ineffective.

  4. Its crazy how fast this industry is going. Every year, they come out with amazing new technology.

    Ive only been in it 6 years and can’t believe all the new advances such as wireless dmx and LEDs.

    Great Article.

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