Is Stainless Steel Band Strapping Allowable To Secure PVC coated RMC?

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mikeanthony827

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I have encountered stainless steel strapping used to support PVC coated RMC on roadway sign structures. I cannot imagine how that could be code compliant. NEC Art 344 doesn't specify types of approved supports. We all know one hole straps, strut straps and MayWests, etc. But Sign Strapping? How can I prove to my quality control colleagues that using stainless steel sign strapping is no permissible by NEC codes? I have scoured the codebook, googled how to find out a materials listed UL uses and I keep coming up empty. Please help guide me. Thanks
 
Does it work?

It seems to me that the important thing is that it works not whether you approve of it or not. Being stainless steel it certainly suitable for the environment and it seems like it would be strong enough. My only caveat would be whether it damages the PVC coating or not.

I'm also not entirely sure that the national electrical code applies to the application that you're referring to. I would take a look at article 90 and see if your application is actually covered by the national electrical code.
 
Stainless steel banding is used all over the country so secure equipment to roadway sign structures. One only has to drive down the highway and look around to see how much banding is used on signs.

Why are you convinced it is a substandard method for securing conduit?
 
mikeanthony827 said:
I have encountered stainless steel strapping used to support PVC coated RMC on roadway sign structures. I cannot imagine how that could be code compliant. NEC Art 344 doesn't specify types of approved supports. We all know one hole straps, strut straps and MayWests, etc. But Sign Strapping? How can I prove to my quality control colleagues that using stainless steel sign strapping is no permissible by NEC codes? I have scoured the codebook, googled how to find out a materials listed UL uses and I keep coming up empty. Please help guide me. Thanks
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Answered your own question there.

Supports do not need to be listed. Is dirt listed when buried or concrete listed when embedded? What about when supported by drilling holes in framing members?
 
Petersonra,
It looks like a hack installed it, doubt it has any substantial rating when it comes to the weight of RMC especially in the event of a vehicle crashing into the sign structure. I would think there is a reason almost all pipe is secured using common methods so when you come across something unusual I think it is fair to ask. I do appreciate your time and I will look over the code again, but I am fairly certain the answer I am looking for lies elsewhere.

Cow,
Signs are not anything like RMC. Both can be heavy sure but this type of banding is used on small signs but are no where near the weight of a vertical riser 50' tall of 1&1/2" PVC-RMC. Also if a sign falls serious damage can be done, but if electrical conduit is disturbed in any way it can cause equal destruction with the added danger of electrical energy. That is my line of thinking in regards to why I believe it is substandard.

Kwired,
Just about every fabricated piece of building material has a UL listing or rating and the code mentions "listed" in almost every single article Supports absolutely have to be listed and approved. Dirt is dirt and in certain arena's can be subject to testing and standards and concrete is usually checked vigorously on large pours. Why don't we just use tie wraps to hold up conduit instead of trapeze?!?
 
mikeanthony827 said:
I do appreciate your time and I will look over the code again, but I am fairly certain the answer I am looking for lies elsewhere.
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The answer you are looking for is the NEC, it just so happens it's not the one you want to hear.[/QUOTE]

Just about every fabricated piece of building material has a UL listing or rating and the code mentions "listed" in almost every single article
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That is incorrect, at least when it comes to strapping and supporting.

Supports absolutely have to be listed and approved.
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It's been a while since someone put this up on the forum but Charlie's Rule is worth taking a look at in the midst of this discussion

Charlie?s Rule of Technical Reading

It doesn't say what you think it says, nor what you remember it to have said, nor what you were told that it says, and certainly not what you want it to say, and if by chance you are its author, it doesn't say what you intended it to say. Then what does it say? It says what it says. So if you want to know what it says, stop trying to remember what it says, and don't ask anyone else. Go back and read it, and pay attention as though you were reading it for the first time.

Copyright 2005, Charles E. Beck, P.E., Seattle, WA
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Charlie’s rule sounds great, if I could find what I am looking for. Four replies many with cryptic opinions and snide. You say the answer is in the code and I couldn’t find it. I thought some fellow tradesmen could point me in the right direction. Perhaps this is a common support method and I have not seen enough traffic work in my career. It looks terrible, does not have the support strength of properly mounted strut or other approved mounting methods using LISTED material and if it is an authority having jurisdiction decision to allow this then we are not wearing our thinking caps
 
Again, that is your opinion, completely unsubstantiated by the NEC. The NEC is a permissive code, if it doesn't state specifically that it is not allowed or has to be done a certain way, then it is allowed.

If you feel as strongly as you do about this, several members on this forum have submitted code change proposals in the past. That is an option. Be prepared to substantiate your claim on why you think the code change is necessary.

Please keep in mind though, just for reference, the NEC allows conduit to be supported by ceiling tie wire. Which has nowhere near the rigidity of a sign structure. I would say stainless banding on a sign post is quite a bit more secure than that. So you will most likely have an uphill battle if you were to propose a code change to not allow banding.
 
I was not being cryptic or snide. And this is the best site on the net to get solid information and feedback from some of the best folks in the trade. What you got was no support for your opinion and that's because there is none. I hope you continue to strive for excellence in the trade, and I hope you continue to participate on this forum.

There is no requirement that straps and supports be listed. One hole straps are not listed, unistrut is not listed unless it is used for a raceway system, unistrut straps are not listed....

There are different levels of requirements for some items in the NEC, listed, identified, and approved.
 
I see no cryptic answers or snide, in fact some very good advice.
For PVC Coated RMC, the appropriate section is 300.11 Securing and Supporting.
I worked on traffic signals and street lighting for 30 years, and was IMSA certified in both. I also wrote NEC articles for the IMSA Journal for 10 + years and was awarded two Journalistic Excellence Awards for my articles. And I am a master electrician and first chief moderator of this forum. If I am at one of Mike Holts seminars, and a question comes up on traffic signals or street lighting, he will often defer to me or have the person email me. I once gave a class on Grounding, one of the lead persons from the City of New York traffic Signal Dept was there, and based on what they learned, they were changing the specs on signal grounding (they have 15,000 signals).
Comments:
1. Use of a Band-It (I have installed a lot of this) for securing P-RMC would work well. If this application is on the outside of a metal signal or wooden pole, it would avoid having to drill and tap a hole in the metal pole or use a SS fastener in the wood pole. Wooden pressure treated poles require SS or HDG hardware as the PT compound is corrosive. Band-It, is fast and easy to install, and can be removed,
2. You mention strut, for P-RMC, it requires a PVC coated strut strap and strut. Is that being used?
3. If you work for a government agency, the simple solution is to write specifications/drawings to support what you want used. My state (WA) DOT has excellent specs/drawings, easy to follow.
3. We would appreciate a picture to see the installation and why it looks terrible. If its no workman like, thats best addressed in specs/drawings.
4. As mentioned, if submit a public proposal for code change. I have had many accepted, including one for a new article.
5. Curious why P-RMC is being used? I have never seen it for a signal.
 
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