In New Constrcution its usually spec'd in the construction documents. Maintain 2" minimum clear or even
greater and that all Services will be independently supported!
It's funny that the NFPA 72 tells us how to attach it and at one lengths
but it will not say that one can't use other structures to do it.
Not that this case doesn't happen, but in those cases that this does usually it due to a limited
application of "Space", and someone in the "Know" will sign off on as to this one type of application.
In the worst case they will use the support rod or structure but never put it directly to another service!
You might check with your Building Codes and get the AHJ to
eyeball this drama!
& IMO;
And of course if we knew where the work is, someone could address this
more exactly as to how to answer this question!
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