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I should know this, but I don't. Educate me.

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scottstephens:
Hey All,

 I was always taught that anything that goes up in the air, must have a safety cable(s) attached.  Is this a law, or common sense or just a CYA ?   I am asking g because a couple a weeks ago, I attended a local Christmas show at a local church and the sound co had 3 QSC KLA's, about 12 ft up on about 40 ft of truss. And on the truss was also 18 small lights. Something like the small par Chauvet's, with just the clamps. Some were on top and some were hanging below the truss.  And there wasn't a safety cable anywhere. No chains or cable on the T-Bar either. Nothing.   Is that legal? Or just stupid? 

Just wondering.

Scott

Tim Weaver:

--- Quote from: scottstephens on January 10, 2022, 11:43:44 AM ---Hey All,

 I was always taught that anything that goes up in the air, must have a safety cable(s) attached.  Is this a law, or common sense or just a CYA ?   I am asking g because a couple a weeks ago, I attended a local Christmas show at a local church and the sound co had 3 QSC KLA's, about 12 ft up on about 40 ft of truss. And on the truss was also 18 small lights. Something like the small par Chauvet's, with just the clamps. Some were on top and some were hanging below the truss.  And there wasn't a safety cable anywhere. No chains or cable on the T-Bar either. Nothing.   Is that legal? Or just stupid? 

Just wondering.

Scott

--- End quote ---


It's a church. They often DIY stuff that they have no business messing with.

Also, I don't think its a "law" that stuff must be safetied, but it is industry best practice. The real enforcement would come from the insurance company denying your claim when the light falls and hits someone on the head.

Also, did these light's have the cheesy plastic cheseborough clamps? Or better yet the piece of bent steel bar with a couple of threaded holes, which always seem to be oriented so that they straight up fall off if the screw isn't tight?


https://www.sweetwater.com/store/detail/CClamp--adj-c-clamp-heavy-duty-lighting-clamp
Look at where the load is, and where the pipe goes. This WILL fall if the clamp isn't tight, and I know that these poorly done course thread holes won't hold tight.

John L Nobile:
All my lamps have safety cables. Don't know if it's a law but my thought is that thumping bass loosens screws and those cans are sharp and heavy. To me it's common sense like "you don't piss in the wind"

Brian Jojade:
Most safety cables are strung through the yoke of the light to the crossbar.  This means the ONLY thing the safety cable is providing protection against is a failure  of the temporary clamp holding the light in place.  Failure of the yoke mounts would cause a light to fall, leaving the yoke in place.

With proper clamps and a normally hung light, the only failure mode would be the clamp physically breaking, or the bolt securing the light coming loose and releasing.  Both are fairly unlikely scenarios once the light is in place.

The most common place that a light would fall is when it's being moved and adjusted, or if someone simply forgot to tighten the fixture in place.

For the fixture that someone forgot to tighten, it would take an inspector time to physically go to each instrument and see that it's secured.  A safety cable allows for a quick visual inspection to see that the light isn't going to fall even if it was installed improperly.

For permanent installs, inspections make more sense, as there is time for that, and therefore stuff gets hung from the air all over the place without additional safety cables.  The nature of temporary lighting leads to more rush installs and inherently more mistakes, thus safety cables are there to protect against that.

In your case, if you looked up at the truss and saw safety cables, you wouldn't think twice about it.  But the lack of safety cables now means you don't know if that light was installed securely or not.

On a positive note, with lightweight fixtures, the power and signal cables can act as safety cables as well, in the event of a failure.  There's enough strength in the cable such that if the light were to come loose, it would hang by the cables and be unlikely to completely fall to the ground. (as long as it's a permanently attached cable and locking XLR connector, that is)

Scott Helmke:
This might be folk wisdom and not modern knowledge, but my understanding about safety cables through the yoke came from the days of those cast iron "Alltman" style clamps.  Supposedly those actually would spontaneously break apart on occasion.

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