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Cable above suspended ceilingHelpful Member!(2) 

franklin97355 (TechnicalUser) (OP)
3 Jan 05 19:06
Can someone tell me where to find reference to the support of cables above a suspended ceiling...(please)
Helpful Member!  ISDNman (Vendor)
3 Jan 05 21:21
National Electric Code (NEC). See 300-11. Probably covered in other sections as well.

May be included in other standards too
Helpful Member!  dhnl (Vendor)
3 Jan 05 21:47
TIA/EIA 569-A Section 4.6

franklin97355 (TechnicalUser) (OP)
4 Jan 05 11:34
Thanks guys.
bikechuck (Programmer)
4 Jan 05 13:45
basically whatever supports your cables should support only your cables. If using plastic devices, make sure they are plenum if necessary
hbiss (Vendor)
4 Jan 05 21:34
National Electric Code (NEC). See 300-11

No, and I sympathize with you for not knowing because the NEC is not easy to understand and I don't think anybody really understands all of it.

Article 300 refers to class 1 wiring- that which would be used for power and lighting, etc. Article 800 covers data and other types of low voltage wiring.

Key thing to understand here is that the requirements set forth in article 300 (also referred to as chapter 3) only cover installations referred to in other articles up to article 725. The requirements of chapter 3 apply to articles 725 and higher ONLY when specifically indicated.

800.5 and 800.6 are the applicable sections here:

800.5  Access to Electrical Equipment Behind Panels Designed to Allow Access
Access to electrical equipment shall not be denied by an accumulation of wires and cables that prevents removal of panels, including suspended ceiling panels.

800.6  Mechanical Execution of Work.
Communications circuits and equipment shall be installed in a neat and workmanlike manner. Cables installed exposed on the outer surface of ceiling and sidewalls shall be supported by the structural components of the building structure in such a manner that the cable is not damaged by normal building use. Such cables shall be attached to structural components by straps, staples, hangers, or similar fittings designed and installed so as not to damage the cable. The installation shall also conform to 300.4(D).

(Notice here we have a reference back to chapter 3).

300.4(D)  Cables and Raceways Parallel to Framing Members
In both exposed and concealed locations, where a cable or raceway wiring method is installed parallel to framing members such as joists, rafters, or studs, the cable or raceway shall be installed and supported so that the nearest outside surface of the cable or raceway is not less than 32mm (1-1/4 in.) from the nearest edge of the framing member where nails or screws are likely to penetrate. Where this distance cannot be maintained, the cable or raceway shall be protected from penetration by nails or screws by a steel plate, sleeve, or equivalent at least 1.6mm (1/16 in.) thick.

To sum up, there is nothing in the NEC that would prevent you from attaching data and telecom cables to suspended ceiling hanger wires etc. It's also up to interpretation (and much debate) what exactly 800.5 means. One interpretation would allow cables to be run on the grid as long as they do not prevent the removal of tiles below other cable or electrical equipment.

Note that the NEC is adopted as code in just about all areas of this country. BICSI, TIA/EIA are only suggested industry standards and carry no weight as far as codes are concerned. Note also that there may be local amendments that have something to say about the subject. The final say is always up to the AHJ (Authority Having Jurisdiction). The AHJ is not necessarily the building or electrical inspector.   




franklin97355 (TechnicalUser) (OP)
4 Jan 05 22:48
Seems to me 300.1 (A) says "This article covers wiring methods for all wiring installations unless modified by other articles."
Sphoneman (Vendor)
5 Jan 05 0:13
Any Data work I've done in New Jersey for the last 3-4 years (different townships- they follow NEC state wide)it has to be supported to structure, in saddle type hangers, & not run on top of the bar joist L channels (as not to damage the cable jackets by the knife points). If suspended lower than bottom of joists you must use separate ceiling hanger wires- not the grid support ones- for your cabling.

PA & DE haven't allowed any wiring to lay directly on grid/ceiling tiles for a number of years.

I had performed a paging installation about 4 years ago where a particular Township required the ceiling tile bridges to be tied with wire in two spots-supposedly due to them being by a fault line.


hbiss (Vendor)
5 Jan 05 21:30
Seems to me 300.1 (A) says...

Franklin, gotta start a book from the begining! Read 90.3, Code Arrangement.

Sphoneman, I agree with you and not only have I never done it any other way it's always been understood that it's a requirement and inspectors will red tag you on it if you do not follow it.

Problem is where is it written? Inspectors are not free to make up rules and if there is a problem they must cite the relevant code sections they believe are being violated. I've given the code sections applicable to this above. What's your interpretation?

If you think an inspector is an expert on the code you are very wrong. As I said above, I don't think anybody really knows the code inside out. Most inspectors know the sections relating to the everyday electrical work they see the most of, but the "technology" stuff can be confusing.

It pays to know as much about the code yourself, or at least those sections relevant to your work. Most inspectors are not hard as** and will be happy to discuss and debate- as long as you know what you are talking about yourself. Make a good point, cite the code sections, and he may even change his mind.

franklin97355 (TechnicalUser) (OP)
5 Jan 05 22:58
So technically the NEC does not cover network cabling at all since it's not in the scope of article 800?
Sphoneman (Vendor)
6 Jan 05 0:35

I've dealt with the best (Ones that know what they want, & tell you the their peves ahead of time,&/ or are responsive to returning your calls by the end of day to answer your questions) & the worst (Don't really look, collect the fees, then write you up for some stupid things- always leave something stupid so that they don't have to look harder to find something to write up) of inspectors. It's not that they are necessarily experts, but they see or have heard of more than we have when problems have come up over the years after the fact.

You can defend your end with any inspector, but do you have the time & the timeline to play with before the GC or the customer needs their TCO.

The codes are written to protect the customer. Be it the present or future landlord, end user, or the public. (Someone to oversee the minimum quality of installations/removations).

The bottom line is that the NFPA is a minimum guideline &  is left up to interpretation by the local juridiction.

 It is their territory & liability if it later results in a lawsuit because of a  potential "fire or safety" situation & that is all they have to cite really.

It covers all low voltage telecommunications media. I would bet that parts of BICSI standards will be used in the future editions.


hbiss (Vendor)
6 Jan 05 13:45
The bottom line is that the NFPA is a minimum guideline &  is left up to interpretation by the local juridiction.

Minimum guideline, yes. But if a jurisdiction adopts the NEC they have to go by it, they can't make up their own rules unless they create formal amendments and can show them in writing. An inspector can't just say "I want it done this way" unless he can back it up.  

True, it often is easier just to do what he wants especially if your a** is on the line, but sometimes if what he wants is going to cost you a lot of money it pays to challenge him when you know you are right.

Keep in mind that many of these "local requirements" are not based on safety but are politically motovated. Why do you think Chicago requires all RESIDENTIAL construction to be wired with conduit? Because the IBEW is a big contributor to the politicians.

It is their territory & liability if it later results in a lawsuit because of a  potential "fire or safety" situation & that is all they have to cite really.

AHJ's, inspectors and municipalities are actually immune from these kinds of lawsuits. Most areas that have licensing will make you sign a hold harmless agreement and require you to name them on your liability policy as a condition of your license. That puts all liability on you and anybody else the lawyers can dig up should something happen, not them.

There was a story awhile back about an old guy who worked part time for a carnival connecting their rides electrically. State inspectors inspected work, kid dies from electrocution. Guess who is in jail.


bikechuck (Programmer)
6 Jan 05 15:28
Inspectors I've worked with in Col. want separate suppport for everything above the grid. Cat5/6 cable are just like any other electrical wires or light fixtures. Now the fixtures have their own support and don't use the grid anymore if you noticed. My experience is grid support wires are just that, grid only. All depends on inspectors if there are any. They don't want anything laying on the grid and lots of times all the old stuff laying on the grid had to be removed if unused.
hbiss (Vendor)
6 Jan 05 20:16
As far as I know they all do and I think we all agree that that's the way it should be done that's why nobody complains about it.

If you are doing any kind of building wiring I urge you to become proficient in the codes involved- it's part of the job. Take a few nights and study through the NEC, learn how it's organized then become familiar with the sections that pertain to you. You don't have to know them by heart, just know where to look.

You bring up a point about abandoned wiring. Per the NEC it must be removed in most cases. This actually could be a moneymaker for you so it pays to know the code requirements.


Sphoneman (Vendor)
7 Jan 05 13:30
I just finished a CAT5 job to replace the Type 1. They are not removing it. They are keeping it entirely intact(Racks, Penels, Faceplates) this way they will not have to pay for the removal. Whenever they move out of the space it will be left for the Building owner or the next tenant to pay for the removal. Pretty slick.


hbiss (Vendor)
7 Jan 05 17:30
Landlords are getting slick to this too. Tell them to check their lease- most now require that the tenant remove what they installed back to the day they moved in. Doesn't matter whether it is usable or not to the next tenant. Guess they are tired of getting stuck.

While we are on the subject of removal, I remember a few months ago there was an article about the discovery that lead compounds were or are being used in the jackets of data and other low voltage cables. Seems after a few years the lead will form a dust on the outside of the cable. They warned about the hazards of removing old cables and said that at some point in the future removal will require the services of a hazmat company. So if they think it's expensive now just wait.

Sphoneman (Vendor)
8 Jan 05 0:00
I will check with some building owners when I get a chance. Usually any improvements to a location become the property of the building owners. That is why all electric is left in place & now they leave the telecom, because the old tenants would just chop off the ends of the cabling & the new tenants thought they would not have to pay for new.

My understanding of the new code, any cabling not tagged to be kept is suppposed to be removed.

Yes, I do know there definetly is lead dust & residue from the jobs that I had removed the old lead cables from.

Just like all the hammerdrilling we used to do years ago without knowing to use ear protection.



hbiss (Vendor)
8 Jan 05 13:54
Yes, I do know there definetly is lead dust & residue from the jobs that I had removed the old lead cables from.

To be clear, these are not lead covered cables that they are talking about. These are the usual plenum and I believe also non-plenum PVC jacketed (cat3, cat5e etc) cables that we use every day. These are said to contain lead compounds in the jacket formulation to limit flame spread and products of combustion.

This could turn into a BIG problem and I suspect that the cost of cable, particularly plenum, will go up if the lead must be removed from the jacket formulation.

Sphoneman (Vendor)
9 Jan 05 21:25

I'm extremely suprised by that statement. They might have to have a new legal spaciality on that.


daronwilson (Vendor)
11 Jan 05 13:57
Geez I just don't have the time to look it all up, but, the 2002 NEC 300.11 (A) talks about support  and says that cables and raceways shall not be supported by ceiling grids.  It also says you can install additional ceiling support wires for the sole purpose of supporting your cables, but, they must be attached at both ends.  As I interpret this, we go in after the tgrid is done and install additional support wires, snap our supports on them if needed, then attach them to the grid.  Some vendors offered tie wires that were painted a bright color to signify that these were not support wires for the tgrid, but for the cabling.

An inspector can't just say "I want it done this way" unless he can back it up.

Actually, he can, and he does.  I performed fire inspections in another life as a fire marshal and yes, if I deemed the situation unsafe, I did not have to pass the installation.  Let me tell you, there are many many more codes and references to pull from (Fire Life Safety Code) for example that may not apply to the construction phase of a project, but does when they want to actually occupy the building.  The only thing that prevents an inspector from making up his own rules are challenges.  I have personally challenged the local inspector three times by calling the state electrical inspector and won on two of them.  These were times he said 'i want you to do it that way' and I said 'show me where I'm required to'.  He bullied everyone else for years, it happens all the time.

Why do you think Chicago requires all RESIDENTIAL construction to be wired with conduit?

Not to say that lobbying isn't a tremendous force, the IBEW takes a fair amount of my money and I don't like them, but let's not forget the famous Chicago Fire (NOT caused by Mrs. Oleary's cow BTW) which quite likely prompted much of the code requirements there, as did the MGM Grand Hotel Fire in Las Vegas (another all conduit jurisdiction).  Having studied fire codes for a few years in that former life, most fire/safety codes are build on experience.  492 people died in the Coconut Grove fire in Boston in 1942 mostly due to overcrowding and egress issues.  The short story is what followed were major changes in the fire code regarding maximum occupancy and egress requirements.  The NEC is a portion of the National Fire Code.


Daron J. Wilson, RCDD

hbiss (Vendor)
11 Jan 05 17:34
Geez I just don't have the time to look it all up, but, the 2002 NEC 300.11 (A) talks about support  and says that cables and raceways shall not be supported by ceiling grids.

Darron, read what I said above. Chapter 3 and article 300 do not apply to low voltage wiring. Article 800 covers it and 800 is really a separate book from the rest of the NEC. The NEC is far less stringent about low voltage than it is about class 1 wiring (power and light).

Seems everybody believes 300.11(A) applies to low voltage, it does not, but that's fine. As far as I'm concerned the support requirements should be the same, can't see why they should be different. What difference does it make if you have a bunch of MC cables or a 6 inch bundle of cat5? This isn't an electrical issue, it's a mechanical issue related to weight.  

The NEC is a portion of the National Fire Code.

Not just a portion but written by them (the NFPA) to cover electrical work.

... most fire/safety codes are build on experience.

Unfortunately hindsight is 20/20.

While I like EMT I challenge anyone to dispute the safety record of other wiring methods such as AC (BX), MC and even romex. If there is a problem, 99% of the time it's because somebody inexperienced caused it, not the wiring. Requirements like this are almost always the handiwork of influential groups wanting to restrict work. Being overly restrictive can backfire because people will find ways to do their own work or hire "trunk slammers" to do it because of the money. When this happens you know that illegal materials are going to be used as well as unsafe work.  

daronwilson (Vendor)
12 Jan 05 16:18
Chapter 3 and article 300 do not apply to low voltage wiring. Article 800 covers it and 800 is really a separate book from the rest of the NEC.

Help me out please, I'm unable to find your reference for this.

300.1 Scope (A) All Wiring Installations.  This article covers wiring methods for all wiring installations unless modified by other articles.

I can find no reference to Article 800 being a separate book from the rest of the NEC.  In fact, Code Making Panel #16 covered Articles 640,650,720,725,727,760,800,810,820 and 830.  The same group of folks worked on ALL those articles.  The table of contents does not reflect anything different for article 800, it is all a portion of the National Fire Code (NFPA 70) as produced by the National Fire Protection Agency.

Enlighten me please, I just don't see where you get to completely ignore chapter 3.


Daron J. Wilson, RCDD

franklin97355 (TechnicalUser) (OP)
12 Jan 05 17:46
hbiss pointed out:


gotta start a book from the begining! Read 90.3, Code Arrangement.
Sphoneman (Vendor)
12 Jan 05 21:29
You go Daronwilson,

I hope you are not up to nine live yet. We have a lot of upcoming posts to be enlightened.


daronwilson (Vendor)
12 Jan 05 22:52
Ah I've been shot at many times before :)

Point well taken, I dug the book out of the truck again and read 90.3.  Actually I think I've gone through this with the inspector before.

Oh well, I'll put this together and go ask him tomorrow.  We don't lay it on the ceiling tile any more, we don't tie to the existing ceiling support wires either.  We don't wire tie the cables to conduits or raceway or sprinkler piping.  

In short, we install supports for our cable and secure it, and I've not had a problem with the inspector for that.

I should have read more closely, sorry, just didn't spot that section.


Daron J. Wilson, RCDD

Sphoneman (Vendor)
12 Jan 05 23:18
You guys have me confused.

I just blew off the dust & dug my 1993 version  of the NEC Code out of my truck.Article 800 is 14 pages long. I can't even find a Article 900. I thought if that is the version I am abiding by, the inspectors must follow that one also.


daronwilson (Vendor)
12 Jan 05 23:26
In Oregon, the state adopts the NEC when it is ready as well as publishing additional requirements that the state has set that are generally more stringent than the NEC.  Also, many cities adopt even tighter code requirements within their jurisdiction.  We are currently operating under the 2002 code, when the 2005 comes out AND after the state adopts it, then we will shift to that code.

Looks like about 18 pages on Article 800 in my code book.  Do you mean article 90?  I don't have a 900 either.

Daron J. Wilson, RCDD

Sphoneman (Vendor)
12 Jan 05 23:30
No wonder I couldn't find it.


daronwilson (Vendor)
14 Jan 05 0:27
Well it was a good learning experience for me.  I checked with my inspector, and he said the only reason he could see would prevent us from tying to the ceiling tie wire would be if they were bundled in a way that prevented the tiles from being opened, or if the ceiling were a fire rated suspended ceiling in which the entire ceiling structure is 'rated' and as such engineered to only support the weight of the sheetrock type ceiling tiles and grid.

Of course, there are other deisgn considerations and other cabling guidelines to consider, but as far as the NEC, it appears it isn't a violation to use the ceiling support wires to support yoru cabling.

Good Luck!

Daron J. Wilson, RCDD

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