Anti-Short Bushings "Redhead" Not Required?

We have been officially advised by NEMA that anti-short bushings are not required when Type MC cables are installed.
http://www.nema.org/DocUploads//8B117E35-EFF9-4B09-B6E4722E1E6DFEF3/BULL90.pdf

The picture here shows a Type AC 90 degree fitting, and the inspection hole shows where the anti-short bushing "redhead" was installed to comply with the Code.

Question: If this fitting was also permitted to be used to terminate Type MC cable would you require an anti-short "redhead" bushing? I think that it would enhance safety and should be installed.

[Linked Image]

I cannot imagine the true or real reason for the different rules!!

[Linked Image]

We still use them Joe. I can't think of a good reason not to.
The "red devil" as we call them,will just about eliminate any chance of damage from the rough edges of the armor.

Russell

What is your preferred technique for cutting the armor. I use the rotary cutting saw (MC goes into a hand-held clamp, you squeeze, and rotate the handle, and the blade cuts the armor. Works _great_, except that the cut goes the long ways and leaves a very sharp point to the armor. I'd think that a 'redhead' is absolutely essential with this sort of cut. I much prefer the _results_ that I get when using a hacksaw...but the rotary cutting saw is ever so much faster.

-Jon

Joe: When you ask "...would you require...", are you talknig from an inspection point of view or an installer's point of view?

As an inspector, I can not require it. See the definition of assualt and malicious prosecution.

As an installer, yes I would ask that my employees use them. Even it eliminates one service call, if was worth the money and time.

There is a third perspective: the customer's.

I as a customer would require them, even if code does not.

Further question along these lines: when you are wearing your inspectors hat, do you verify that the installation is up to code, or do you also verify that the installation is up to whatever additional requirements the customer has specified? So, for example, if I as a customer requested anti-short bushings, and this was agreed to in the bid, is it the business of the inspector to report this if they are noted to be missing?

-Jon

If this fitting was used as I asked, "I would insist on the "Redhead" and would dare the Judge and Jury to yank the cable while it was energized feeding this furnace.

Let's not have the new kids become brainwashed by the code, those with only a short time in the field with the tools.

Most "seasoned mechanics" would agree "put the red devil" in and be done with it!

This is another issue that will grow so old it will be able to vote!

PS: I used the hacksaw for the time when I worked in the field and the tool that cuts the armor is good too, but still leaves a sharp edge.

Joe you have me totally confused.

It was you that posted a statement from NEMA or UL that clearly stated they are not required.

The NEC does not require them.

So what are you saying with this post?

By the way I use them and expect the workers under me to. [Linked Image]

Bob

Bob:

If the fitting I posted above was used it would expose the end of any Type AC or MC, cable and I would call for the bushing.

I am sure that the NEMA report is what everyone in the field understands and believes.

I would challenge each of the members of that committee to install a piece of AC and MC cable in the same box and expose the MC to a fault at its termination in a fitting, however you want, and the lack of the bushing will prove a point --- it will cause an arc, and a fire and create a hazard.

I call for a public meeting in a place where we can perform this test and see the results, or maybe someone would agree to do a video of the same test?

PS: I am glad you do approve of the use of the busings anyway, you are a "seasoned mechanic"!

Joe,
'yanking' live wiring through any number of raceways would probably result in fireworks despite the best of installs...

of course, should NEMA choose to pursue this manner of testing, i'm sure there will be an accomodating NRTL

~S~

Joe how can you say "I would call for the bushing"

You have no code article to cite.

Now in reality if I was presented with this situation it would be easer to put the bushing in than fight the inspector on this.

But an inspector is to enforce the code and not his or her own preferences right? [Linked Image]

Bob

OK then, maybe this would work:

A permit and plans have been submitted for a plan review and the AHJ begins that procedure, and in the specifications it states that "NEMA says we don't need the bushings", and I ask the question:

"Are you planning not to use bushings? You say, I plan on it anyway and I will use the bushings."

Some electricians have to wear the AHJ hat for a while, and that may come later after they tire from the cold, and climbing the ladder, and the dirt and sore back!

Bushings are required for AC but not for MC cable.

If they have been deemed "not required" then why do the manufacturers still go through the trouble and cost of attaching a complimentary bag with each spool? Just curious??

Tradition

We would ask for them [Linked Image]

I actually had to buy some recently.

I often grab up partly used 1000' spools from job close outs and all the red heads are gone.

I wonder how many of us would feel comfortable about the job if we didn't use'em?

Russell

As a unbiased comment to this thread, some manufacturers recomend using "anti short" bushings on MC regardless of code requirements. Now with that said, does this manufacturers "recomendation" mean anything or have any substance as far as liability is concerned?

Roger

Remember about 10 years ago red devils where redesigned with the little points sticking up so inspectors could see them being used.
Every fault I have seen in an m/c install was do to the lack of not using a bushing!
It should be a code requirement, not a design issue!

I always use the redheads, but they often tend to fall out of the cable unless secured with a wrap of tape.

AC cable allows you to backwrap the bonding wire to secure the redhead...

After all is said and done, the listings and code call for the use of "approved fittings" be used for termination. Most if not all AC fittings are not approved for terminating MC cable. MC fittings have a guide built in that hold the wire centered, away from the edge. AC connectors do not. The biggest problems I have seen analyzing failed industrial equipment have been 1)cutting MC or AC with improper tools; 2) using AC connectors with MC cable and no bushings; 3)failing to properly torque the termination fitting so that the cable pulls out. The next time you go to the supply house to get MC fitting, especially 90s, look and see exactly what you get. You might be surprized.

Here is the text from NEMA statement on Anti-Short bushings that Joe and I referenced.

You can download it from NEMA here.
NEMA Bulliten 90 Use of Anti-Short Bushings (pdf)

Quote

NEMA ENGINEERING DEPARTMENT BULLETIN No. 90

August 14, 2002

Use of Anti-Short Bushings for Terminating Type MC Cable

There has been much confusion within the Installation and Inspection communities regarding the use of anti-short bushings for terminating Type MC cable. The confusion stems from the fact that some MC cable manufacturers include anti-short bushings with their cable. The inclusion of anti-short bushings with coils or reels of MC cable is based on historical practice relating to the requirements of 320.40 of the NEC, which mandates the use of anti-short bushing or its equivalent protection for Type AC Cable.

Fittings used with Type MC Cable are required to be listed per 330.40 of the NEC. NEMA supports the use of listed fittings for MC Cable. The design of these fittings may or may not include an insulated throat however, they are required to be provided with a smooth, rounded end stop so that the metal sheath of the cable will not pass through and the wires will not be damaged in passing over the end stop. Whether or not an insulated throat is part of the listed product, these listed MC fittings do not require an additional anti-short bushing. Anti-short bushings that may be supplied by MC Cable manufacturers are for optional use by the installer, however they are not required.

ROP #7-116 from the May 2001 Report on Proposals (ROP) for the 2002 NEC was a proposal seeking to require anti-short bushings on all MC Cable termination installations.
The following is an excerpt from the Panel statement rejecting the proposal:

Anti-short bushings are not required for Type MC cable in accordance with the listing for the product. The termination fittings approved for use with Type MC cables are designed such that the wires will not come in contact with the cut edge of the armor; the throat of the fitting is small enough to prevent contact with the armor. Type MC termination fittings perform the same function for Type MC cable as Type AC terminations plus the anti-short bushing do for Type AC cable.

NEMA supports the uniform adoption and enforcement of the NEC and recommends that local Authorities Having Jurisdiction follow the requirements of NEC Section 330.40, Boxes and Fittings for MC Cable. Section 330.40 requires that the fitting be listed, but does not mandate the use of an anti-short bushing.

Distribution List:
Standards and Conformity Assessment Policy Committee
Codes and Standards Committee
NEMA Executive Staff

I ALWAYS use them.
The hole in the fitting is for inspecting the required AC bushing.
ALWAYS use them, why not, they're FREE!!
...S

[This message has been edited by electure (edited 11-28-2003).]