The following letter is copied from Mike Holt's Weekly News Letter

Use of Anti Short Bushings for Terminating Type MC Cable

Dear Mike,

In the past I have emailed you questions on the code and your responses are most
respected in the field. I am quite disturbed by the NEC's lack of clarification of the usage of anti-short bushings, AKA "Redheads," in the application of MC cable installations. I have seen that the NEC only addresses its usage in AC cable and does not apply it to MC cable.

Common sense is to use them with all armor cable installations. I have personally had applications blow up in my hand when people do not use them. I am an advocate of its usage and strictly monitor my apprentices.

I do truly wish for some clarification and strict correction in the NEC. I also have argued the fact that the bushings installed in "speed lock" and "push in" connectors is to protect the wire from the connector only and DOES NOT replace the anti-short bushing that protects the wire from the armor cable sheath.

I await your response and do hope that it is addressed in the EC&M magazine as it is regarded as clarification to Code and read for corrections.

Thank you Kindly Sir

Derek
Englewood, CO

Mike Holt's Response:

Derek, I can understand your frustration, but this issue has been clearly address by the NEMA Engineering Department Bulletin No. 90, titled Use of Anti-Short Bushings for Terminating Type MC Cable.

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 Bulletin No 90 on MC Red Head Bushings

Grounding and Bonding Information:

The Southwestern Section of the International Association of Electrical Inspectors prepared an excellent set of documents that address the subject of Grounding and Bonding that we believe should be available to the public and in particular to our members and friends of IAEI.

We have attached them to our website as information available that may prove to be helpful for individuals, jurisdictions and others who are interested advancing their understanding in the subject of Grounding and Bonding of Electrical systems and circuits.Legally we make No Claim to the accuracy or technical content and leave the approval of the application of this information strictly up to the Authority Having Jurisdiction in your area to validate or approve installations within their jurisdiction that have been based upon this information. This information is offered as general information only and should not be considered a technical specification or the way that your jurisdiction allows you to install the grounding and bonding of systems.

We do feel however that these documents are important and represent clear guidance in the absence of any direction or for jurisdictions to be able to have a starting point for developing their standard installation. Authorities Having Jurisdiction does include local municipal building and planning departments, Local Utilities where the grounding is ahead of the Main Disconnect, State and Federal Agencies and Insurance Companies where applicable. Check Articles 80, 90 and 100 of the Code Year that your jurisdiction has adopted for the proper definition of Authority Having Jurisdiction.

Grounding and Bonding Pamphlet (Click Here)

Service Grounding and Bonding Diagrams (Click Here)

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Major NFPA Documents that directly interface with the National Electrical Code NFPA-70 are:

NFPA-70B Recommended Practice for Electrical Equipment Maintenance
NFPA-70E Standard for Electrical Safety in the Workplace
NFPA-79 Electrical Standard for Industrial Machinery 2002
NFPA-99 Healthcare Facilities

Other documents that are related to the National Electrical Code Are:
UL 508A Industrial Control Panels
OSHA 1910.200 and 300 sections
NEMA MG1, IC2, IC3
ANSI/NECA NEIS 1 thru 29