Cabling-hanging and the NEC

Q: At the recent Cabling Installation Expo `97 in Charlotte, NC, a letter was distributed by one of the vendors stating that according to the National Electrical Code (NEC) and the revised tia/eia-569a, it is permissible to attach appropriate cable fasteners on suspended ceiling support rods or wires that may carry multiple cables. They state in the letter, "But what happens if the local inspector will not permit it? Here are the facts: Nearly all local codes are based on the nec. There is a pro

Q: At the recent Cabling Installation Expo `97 in Charlotte, NC, a letter was distributed by one of the vendors stating that according to the National Electrical Code (NEC) and the revised tia/eia-569a, it is permissible to attach appropriate cable fasteners on suspended ceiling support rods or wires that may carry multiple cables. They state in the letter, "But what happens if the local inspector will not permit it? Here are the facts: Nearly all local codes are based on the nec. There is a provision in the nec, Article 90-3, `Code Arrangement,` that says, `Chapter 8 covers communications systems and is independent of the other chapters except where they are specifically referenced therein.` Article 300-11 is not referenced in Chapter 8, therefore its restrictions do not pertain to telecommunications systems."

To begin with, this sounds like an interpretation of the NEC. I wouldn`t want to be butting heads with an inspector after the fact, especially when a deadline is looming. Also, I checked with the City and County of Denver inspectors in Colorado and they informed me that this practice is illegal according to the Uniform Building Code used in their jurisdiction. The same was true for the City and County of Boulder.

Is the local inspector the definitive source of information on codes in a situation like this?

Scott English, President

Data Structures Inc.

Louisville, CO

A: contend that every time someone reads a section of the code, that person makes his or her own interpretation as to what was intended. It is the nec Committee`s challenge to write a document that is as unambiguous as possible. However, a peek inside the front cover will show you that the code is written primarily by people representing product manufacturers--each attempting to protect its own turf.

erico has done its homework-- so well, in fact, that it convinced the TR-41.8.3 Working Group to remove the previous "shall not" statement in the newly published ansi/tia/eia-569a. Its argument was "harmonization with the NEC."

Your question reminds me of the old public-service announcement in which an ominous state trooper standing in front of a fatal traffic accident pointed at you and said, "You can be right--dead right." I agree with you that the real concern to the contractor, installer, and end-user is this: What does your authority having jurisdiction--the local building inspector--think the NEC is saying?

Donna Ballast is a communications analyst at The University of Texas at Austin and a BISCI registered communications distribution designer (RCDD). Questions can be sent to her at:

Cabling Installation & Maintenance or at PO Drawer 7580,

The University of Texas,

Austin, TX 78713;

tel: (512) 471-0112,

fax: (512) 471-8883,

e-mail: ballast@utexas.edu.

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