It’s December, winter is here, and the past year’s summer time outdoor events are far behind you by now. It’s time to start planning for next year, with equipment and staffing projections lurking underneath those piles of project documents you have to review for a bid that’s due next week. “I’ll get to it”… you say, but right now you have a standing appointment to address those regular daily business matters, while equally pressing project fires ignite with their usual flare, sure to interrupt at any time. That’s business. That’s entertainment.

Wake up. Look around. We’ve seen roof system collapses, reminders that bad things can happen to good people. Please take a moment to evaluate your current state of preparedness, and consider the following questions.

How many incidents did you experience this year, beyond what everyone’s heard about?

Many incidents go unreported. These are land mines of avoidance, classic examples of why you should reassess your procedures to implement and enforce proactive measures so incidents don’t happen.

How many near-misses did you have this year?

Have you seen things, overlooked or avoided things that in retrospect made you breathe a sigh of relief for the fact that it wasn’t you, knowing it could have been? Reality check: those things you saw happened to someone.

When was the last time your system was inspected?

I don’t mean the frequent inspection that might have happened last time someone looked at the end of a truss because they were bolting it together while assembling your most recent event. I mean when was the last time your system was inspected? Section 6 of ANSI E1.21-2006 requires both frequent and periodic inspections. Frequent inspections are required prior to each use and immediately after an incident that may have caused damage. Periodic inspections are required at least annually and the system must be removed from service for this inspection. They must be documented.

If your system is aluminum, then ANSI E1.2-2006 also requires inspections. The requirements of both standards are consistent with each other in that they intend for the user to establish routine, regularly scheduled inspections and documentation procedures. It’s an industry standard.

In this respect nothing is as important to us as keeping the public aware of safety.

Do you have an Operations Management Plan (OMP)?

In our opinion, there’s no reason to not have a response plan to address foreseeable hazards. Repeat: foreseeable hazards. Consider that an operations management plan is nothing more than a choreographed script, to which our industry is inherently accustomed. As an industry we pride ourselves on being capable of reacting to the most adverse condions under the most restrictive time constraints. That’s entertainment.

Work with the rest of the industry to keep it safe. In this respect nothing is as important to us as keeping the public aware of safety.

Do you have engineering documentation?

E1.21 also has extensive engineering requirements, from design through manufacturing. Analysis of the system is necessary for proof-of-design, to verify such critical information as payload capacity, and to determine the lateral force resisting system criteria. This analysis produces engineering controls which in turn support the administrative controls required to be detailed in the Operations Management Plan. Engineering analysis is required for compliance with ANSI E1.21. If you do not have this documentation, start with your system manufacturer. Most manufacturers maintain information on standardized system configurations, but if it’s not readily available there, ask a structural engineer who specializes in these systems for assistance. If your system is customized in any way, that’s all the more reason to get it. And, let’s face it: engineering isn’t cheap, but the alternave risk exposure costs far more, especially when lives are at stake.

Your engineering documentaon must also contain detailed drawings of the system (its components and connections), especially critical load path elements and the lateral stability system – all are important detailing requirements.

Did you know that one engineering review cannot consider all possible load cases?

Each installation is different; each show has different production requirements and therefore different load cases placed on the system. Granted, uniformly distributed load (UDL) cases are generally easy to analyze, but are frequently challenging to replicate in an actual show condition. When UDL’s are supplemented with point loads, each point load location changes the truss behavior. However, the real culprit in these load cases is the interaction between gravity loads and lateral loads, and this culprit lurks in the midst of all load cases, hiding in the member interactions. Make sure you have your engineering processes in order, so you can in turn make sure your OMP is up-to-date.

Do you assign an on-site designated person to your shows?

The designated person is one who understands the system, its engineering and administrave controls, and is the person who will implement the OMP requirements when it’s time. Section 5 of E1.21 requires a designated person on site at all times when systems are in use.

Structure safety is imperative. Help keep our industry, and the public, safe with these tactics in mind.

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