Friday, June 28, 2013

Gut Feeling Can Prevent Accidents

A Pat Benatar benefit concert scheduled for Friday, June 21, 2013 was cancelled at the bequest of her stage crew.  Upon arrival to the venue, an outdoor covered arena in Iverness, Florida, the crew was presented with a stage platform that they did not think was robust enough for the show.  Rather than risk the potential for a structural collapse, they requested that the promoter have the stage structure inspected and reinforced.  A local engineer was brought-in to certify the stage, but the caveats included with the inspection did not satisfy them in time to mount the show.

An article at Celebrity Examiner (www.celebrityexaminer.com/2013/06/26/benatar-releases-photos-of-substandard-stage) describes the scenario at length. Below are some picture released by Pat Benatar and her husband Neil Biraldo that show the deficiencies they found.  It is noteworthy that a performer and crew would postpone an event until it can be presented safely, rather than throwing caution to the wind and saying "Damn the torpedos - full steam ahead!

Just because it might have worked doesn’t mean you shouldn’t give it a second look.   If something looks ‘hinky’, give it a good going-over.


WalkerFest Stage
Upstage End Looking Towards Downstage Right

I’ve seen stages with these types of support legs before, and they are generally pretty strong as far as static column loading, which may have been the assumption by the engineer that allegedly certified the stage.  He may have not been considering the lateral dynamics of movements on the stage during load-in, performance, and strike.

The lack of regular diagonal (cross) bracing would make it a wobbly experience.  Note that the 2x4 diagonals shown along the upstage end are not pinned in place to fix their length, instead, they are only pinched against the suport legs with C-Clamps, a connection that can slip loose when loaded becasue it is only held together by friction.

 
WalkerFest Stage
Understage View Looking From Upstage Towards Downstage Right

The understage picture shows the manufacturer’s Quick Connect Braces along the downstage row of support legs, but does not show any other intermediate braces or braces along the side stage support legs.

Surprisingly, the manufacturer’s catalog (www.graniteind.com/DOWNLOADS-SeatingStagingFencing.asp) has a chart of the required number of diagonal braces (not cross-braces) that are recommended for stages of various sizes, and it appears to advocate only installing the diagonal braces at about 50-90% of the perimeter locations, with none at the interior supports; whereas their competitor, BilJax (Model ST8100, www.biljax.com/products/events, also sold as AlphaDeck in Europe, www.alphadeckstaging.com recommends a higher number of X-Braces along both axes and between the interior support legs.

The stage in the photos appears to be about 54” tall (as measured by counting the hole spacing in the legs), and according to both Granite and BilJax, stages over 48” tall should have two sets of braces at the recommended minimum spacing.

Stages need diagonal bracing along both axes,  not just one, and all support legs should be braced to prevent them from being skewed from vertical by unexpected circumstances.

The 2x2 or 2x4 stringers seen running along beside the support leg feet do not appear to be attached to the support legs, but even if they were, they would only serve to keep the feet spaced relative to each-other, not to counteract any parallelogram type collapse of the structure.  Diagonal X-braces would both prevent the legs from tilting away from vertical and provide sway-bracing for the entire stage structure.

The foot-pads on the ends of the support legs are resting on what appears to be a dirt arena floor (but it could be dust on a concrete floor, or a canvas drop-cloth – it’s really difficult to tell from the pictures).  Note the plywood square ‘mud seals’ lying adjacent to each leg – they were NOT installed, so the legs could sink into the surface below if it is not a concrete deck.  The ground surface appears dry in the picture, but that doesn’t mean it will stay dry; nor does it mean that the ground is dry and compacted below the visible surface.

HEY!  Er, ah, HAY!  What's that hay doing under the stage?  It's a fire hazard that should have been removed, too.

Show Some Moxy.  If it 'just don't look right', then verify that it will be safe.  Risk Analysis is part of your job!

1 comment:

  1. Bill Reynolds, the Director of Theater Safety and Occupational Health at Yale School of Drama/Yale Repertory Theatre, commented that "Stages over 48 inches tall [in many jurisdictions] should have fall protection railings. There appears to be a piece of railing in the left edge of one photo. The entire backstage perimeter should have railings in place before work is done on the elevated stage deck. The downstage/audience side edge of the deck could [should] have temporary railings during load-in that are removed for performances.

    It's good that performers and road crews are checking and asking these questions. And demanding better and safer venue setups."

    Another good reason to have railings is to keep those road cases full of expensive fragile equipment from rolling off of the stage. At just a few hours before showtime, it is good to have equipment that is functional and not in need of a trip to the repair shop! Not to mention the royal PIA it is to hoist a fallen road case back up onto the stage - especially if it is filled with electrical cable - those are really heavy!

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