InspectAPedia ^TM

The Aluminum Wiring Information Website ElectricAPedia © Enter your search terms Submit search form   Search This Website - InspectAPedia.com

This website answers nearly all questions about aluminum wiring inspection, hazards, repairs How to identify & repair aluminum wiring What are the hazards of aluminum electrical wiring? What is copper wire pigtailing? Sources of COPALUM electricians & alternative aluminum wiring repair methods Our site offers impartial, unbiased advice without conflicts of interest. We will block advertisements which we discover or readers inform us are associated with bad business practices, false-advertising, or junk science. Our contact info is at inspect-ny.com/appointment.htm. Photos above show an improper aluminum-to-copper pigtail splice which is overheating, and an infra-red photo of the same connection, from a more distant view (courtesy of G. Cohen). Aluminum wire connections can overheat enough to start a fire without ever drawing enough current to trip a circuit breaker. © Copyright 2008 Daniel Friedman, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. Use the links at page left to navigate this document or to go to Other Website Topics. Green links at left show where you are in our document & website.

ALUMINUM WIRE RISK: The Aluminum Electrical Wiring Risks & Hazards Explained

Aluminum wiring, used in some homes from the mid 1960's to the early 1970's, is a potential fire hazard. How safe is aluminum wiring? According to the U.S. Consumer Product Safety Commission, fires and even deaths have been reported to have been caused by this hazard. Problems due to expansion, or more likely micro-fretting and arcing at the connectors, can cause overheating at connections between the wire and devices (switches and outlets) or at splices. The connections can become hot enough to start a fire without ever tripping a circuit breaker!

The photos shown above are not the most dramatic catastrophes linked to fires caused by aluminum wiring. But these are conditions that are found in many homes with aluminum wiring, confirming that this is a real, common, and widespread hazard.

CPSC research shows that "homes wired with aluminum wire manufactured before 1972 are 55 times more likely to have one or more connections reach "Fire Hazard Conditions" than are homes wired with copper. "Post 1972" aluminum wire is also a concern. Introduction of the aluminum wire "alloys" in 1972 time frame did not solve most of the connection failure problems. Aluminum wiring is still permitted and used for certain applications, including residential service entrance wiring and single-purpose higher amperage circuits such as 240V air conditioning or electric range circuits. The fire risk from single purpose circuits is much less than for branch circuits. But it's not necessarily because of a "new alloy" as some folks assert. It's because there are enormously fewer connections (four or six rather than 30 or 40 per circuit) and thus statistically a smaller chance of a connection failure. These connections do still burn up, as indicated by field reports.

Use links at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

More Information on Aluminum Wiring Hazards and Other Building Diagnostic Inspections and Repairs

• The Aluminum Wiring Information Website Aluminum Wiring Hazards and Repairs: in-depth info, photos, documents. Main Page.
• The Aluminum Electrical Wiring Hazard Explained (in the document you are presently viewing)
• How to Recognize or Identify Aluminum Wiring
• How to Reduce the Risk (how to repair aluminum wiring) in Buildings with Aluminum Electrical Wiring - Overview of Acceptable Repair Practices (in the document you are presently viewing)
• COPALUM Electricians: Sources of TYCO COPALUM -Certified/Trained Aluminum Wire Repair Services (in the document you are presently viewing)
• COPALUM Aluminum Wire Connector Availability: How to Get the Proper Aluminum Wire Connectors - U.S. CPSC announced that Tyco Electronics Corp. will continue offering the COPALUM connector repair system until at least 2005 - for details see the US CSPC-Tyco Press Release.
• Other Products, Ideal 65 Purple Twister (not recommended), & other Aluminum Wire Products/Articles (in the document you are presently viewing)
• Aluminum Wiring Bibliography: extensive resources on Aluminum Wiring
• Aluminum Wire Failure Reports & Photos Real life aluminum wiring field failure reports can be seen at inspect-ny.com/aluminum/wirefire.htm
• How to Identify Aluminum Wiring, recognition photos and tips
• 05/21/2007 Reducing the Fire Hazards in Aluminum-Wired Homes, [.PDF document], Jess Aronstein, Ph.D., 21 May 2007. This document answers most technical questions about the hazards and remedies of aluminum electrical wiring and includes a report on independent test results of alternative products and methods for repairing aluminum wiring. Some of the sections of this very thorough document are listed below:
• 02/09/2006 Reducing the Fire Hazards in Aluminum-Wired Homes, [HTML document], Jess Aronstein, Ph.D., This older version of the above document also answers most technical questions about the hazards and remedies of aluminum electrical wiring but lacks latest repair product testing such as the AlumiConn connector discussed above. Some of the sections of this very thorough document are listed below:

  COPALUM Copper-to-Aluminum Pigtailing Use the special AMP (now TYCO) COPALUM connector and special tool to connect short copper wires to every aluminum wire end in the Building, reconnecting the copper to the various devices (outlets, switches, lights) and splices. The TYCO COPALUM connector method is described is described at PIGTAILING USING AMP "COPALUM" CONNECTORS. COPALUM Aluminum Wire Connector Availability discusses how to get these aluminum wire connectors

  AlumiConn TM aluminum to copper lug connectors [New in 2006, U.L. Listed, 2007 completed independent testing] available from King Innovation. Results of independent testing indicate that this product "... is predicted to have a high probability of failure-free long-term safe performance, PROVIDED THAT THE SETSCREWS ARE CAREFULLY TIGHTENED TO THE MANUFACTURER'S RECOMMENDATION".

  Scotchlok 3M Special Method [- superceded by new alternate repair as of June 2007 -]: this ""Scotchlok 3M Special Method was previously recommended as independent tests showed that it performed acceptably. While this repair method has been superceded by new alternate repair as of June 2007, we have kept this description available to aid home buyers, electricians and home inspectors who may discover or need to be able to recognize this aluminum wire repair method if it was previously used in the building. A summary of this method is at "Scotchlok 3M connector" and details of this method are at Aluminum Wire alternative repair: Special Aluminum Wire Repair Method

  
  

  Other methods - not recommended: Warnings regarding other "repair" methods which are not recommended are discussed at OTHER REPAIR PRODUCTS, such as the Ideal 65 purple "Twister" connector shown in the photo at left (12 connectors cost $49. to $79.), receptacles and outlets marked "COALR" (even if these worked, which has not been demonstrated, what about all of the other electrical connections and splices in the building?) and others.

• Fire Hazards With Aluminum to Copper Twist-on Connectors & Acceptable Aluminum Wiring Repair Practices Color Photos, Current Issues. 9/28/95 CPSC Meeting Minutes
• "Is YOUR Aluminum Wiring Safe?" article discussing safety claims made by some people without looking at the wiring, J. Aronstein, 11/21/95
• "Repairing Aluminum Wiring," U.S. Consumer Product Safety Commission Publication CPSC#516 available online



• Electrical Safety Hazards and Safe Electrical Inspection Procedures for Electrical and Home Inspectors at Residential Electric Panels
• Circuit Breaker, a bad one fails to trip failure at aluminum bus-to-circuit breaker connection - field report and photographs
• Electrical Panels, How to Inspect in Buildings, safety for electrical inspectors, electrical panel, fusing, wiring defects, defective products. Inspection Class Presentation
• Electrical System & Wiring Hazard Inspection, Detection, Cause, Remedy, Prevention - Main Electrical Page
• Directory of Home Inspectors accessible via Internet


• Southwire Corporation, manufacturer of aluminum (and other) wire products
• Consumer Product Safety Commission various information resources
• What Owners Need to Know About [Aluminum] Wiring Dangers, Sandra Fleishman, Washington Post, 3 July 2004 pF01
• Carson Dunlop's Home Inspector's Home Study Course (DJF is a contributor and participant in this education project).
• FAQs on author/website credibility

InspectAPedia ^TM Home & Site Map - Building Inspection, Diagnosis, & Repair, Environmental Inspection & Testing - Research Website

Home Inspection Construction Consulting Services & advice for home buyers

Contact Daniel Friedman for website content suggestions or for fee-paid consulting

	Enter your search termsSubmit search form
	Search This Website - InspectAPedia.com

The Aluminum Wiring Website Home Page is at www.inspect-ny.com/aluminum/aluminum.htm

07/22/07 - 04/01/1995 Aluminum Wiring Home Page www.inspect-ny.com/aluminum/aluminum.htm © Website design and content Copyright 2006 1986 Daniel Friedman, All Rights Reserved

HOW TO REDUCE THE RISK of Fire and Electrical Circuit Connector Overheating in Buildings with Aluminum Electrical Wiring

Immediate Actions for Safety of Aluminum Wiring

• See if you have aluminum (solid conductor branch circuit) wiring installed in your home. Aluminum wiring identification tips are provided below.
• If there are signs of wiring failure, such as flickering lights, turn off the circuit involved and call a licensed electrician. See U.S. CPSC 516 (linked-to below) for other trouble signs.
• Install smoke detectors.

How to Repair Aluminum Wiring

Once the initial steps above have been addressed:

• Re-wire the Building replacing all aluminum branch circuit wiring with copper, as a "best repair method" for aluminum wiring, OR as a next-best aluminum wiring repair method,

Currently only these two remedies above have been formally recommended by the CPSC. Other aluminum wiring repair connector products have been sold by various manufacturers, some with good performance and some unacceptable. Descriptions are below. Emergency temporary repairs necessary to keep an essential circuit in service might be possible following other procedures described by the CPSC or by industry experts.

• Aluminum Wiring Repair Method Details including step by step instructions for recognizing and repairing aluminum electrical wiring hazards are provided below.

Use links at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

HOW TO ID & REPAIR ALUMINUM WIRING: Aluminum Wiring Repair Method Details and other research articles about Aluminum Wiring

• How to Identify Aluminum Wiring, recognition photos and tips
• 05/21/2007 Reducing the Fire Hazards in Aluminum-Wired Homes, [.PDF document], Jess Aronstein, Ph.D., 21 May 2007. This document answers most technical questions about the hazards and remedies of aluminum electrical wiring and includes a report on independent test results of alternative products and methods for repairing aluminum wiring. Some of the sections of this very thorough document are listed below:
• 02/09/2006Reducing the Fire Hazards in Aluminum-Wired Homes, Jess Aronstein, Ph.D., This older version of the above document also answers most technical questions about the hazards and remedies of aluminum electrical wiring but lacks latest repair product testing such as the AlumiConn connector discussed above. Some of the sections of this very thorough document are listed below:
  [UPDATED-DF 3/8/2003, Edits-df 02/09/2006]
  Pigtailing using COPALUM - CPSC recommended,
  Pigtailing using Scotchlok 3M - a tested, useable aluminum wiring connector method, with a link to step-by-step "how to" photos,
  Pigtailing using Ideal 65 - NOT recommended, aluminum wiring failures research, field and lab experience, expert sources.
• COPALUM Aluminum Wire Connector Availability: How to obtain the proper Aluminum to Copper Pigtail Connectors - U.S. CPSC announced that Tyco Electronics Corp. will continue offering the COPALUM connector repair system.
• Aluminum wiring failure reports and photos from existing installations.
• Fire Hazards With Aluminum to Copper Twist-on Connectors & Acceptable Aluminum Wiring Repair Practices Color Photos, Current Issues. 9/28/95 CPSC Meeting Minutes
• "Is YOUR Aluminum Wiring Safe?" article discussing safety claims made by some people without looking at the wiring, J. Aronstein, 11/21/95
• "Repairing Aluminum Wiring," U.S. Consumer Product Safety Commission Publication CPSC#516 available online
• (AMP) TYCO COPALUM CONNECTOR - this one works and is US CPSC-recommended for Aluminum Wiring Pigtailing Repairs
• Jan 2005 - Tyco Electronics website provides information about the AMP COPALUM connector program
• AMP Corporation, Harrisburg PA 17105 800-522-6752 - CPSC's recommended COPALUM aluminum-copper retrofit - US Customer Support 800-522-6752 [See the TYCO announcement above]
• AMP Canada Product Information Department, 905-470-4425 the COPALUM connector line is available in Canada; they do not appear to have a contractor training/certification program such as is (at least in a few places) available in the USA.
• Jan 2005 - AMP COPALUM Connectors & Equipment Source for at Tyco Electronics
• May 2003 COPALUM Aluminum Wire Connector Availability: U.S. CPSC announced that Tyco Electronics Corp. will continue offering the COPALUM connector repair system.

Use links at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

Online Directory of REPAIR ELECTRICIANS: Sources of AMP TYCO -Certified COPALUM Trained Aluminum Wire Repair Services

The following electricians are certified in copalum residential aluminum wiring re termination, or "copper pigtailing" to aluminum wiring using the special and US CPSC-approved COPALUM connector and the COPALUM Re termination Tool:

• Colorado directory of aluminum wire repair electricians:
• White Knight Electric - Denver AMP or TYCO COPALUM certified, 303-745-1662 - contact Paul Szynskie, Owner service@whiteknightelectric.com
• Colorado, Aurora, Denver - Front Range-Aluminum Wire Repair, Inc., AMP or TYCO COPALUM certified, 720-299-4706 or 800-509-5695 contact Alex Costantino, info@alwirerepair.com
• Florida directory of aluminum wire repair electricians:
• Naples - 1st Electric, LLC, Roy Jay Dutcher, Toll Free 1 (866) 933-0111 - will travel to other states Roy@RoyDutcher.com authorized Tyco Amp COPALUM contractor
• Kentucky directory of aluminum wire repair electricians:
• Louisville - The Power Network, AMP or TYCO COPALUM certified, 502-693-2888 / 502-945-3917 fax, Mike Bauerla certified for aluminum wiring repairs and copper pigtailing to aluminum wire
• Missouri directory of aluminum wire repair electricians:
• St. Louis - Direct Electric, Don Cherry, 636-462-5028 DLCherry@gmil.com Electricians Specializing in Aluminum Wire Repair, Federal Pacific Stab-Lok Replacement, Zinsco Replacement
• North Carolina directory of aluminum wire repair electricians:
• North Carolina - R.W. Schoolfield, Electrical Contractors, TYCO Connector Aluminum Wiring Repairs in N.C., 336-378-9821, 336-378-9821 fax, rwsec@bellsouth.net
• Ohiodirectory of aluminum wire repair electricians:
• Cincinnati Cooper Electric - AMP or TYCO COPALUM certified for aluminum wiring repairs and copper pigtailing to aluminum wire
• Cincinnati Curry Electric- COPALUM repairs, Justin Burroughs, 513-752-5454 justin@curryelectric.com
• Cincinnati Leitner Electric - AMP or TYCO COPALUM certified for aluminum wiring repair
• St. Clairsville - 1st Electric, LLC, Roy Jay Dutcher, Toll Free 1 (866) 933-0111 - will travel to other states Roy@RoyDutcher.com authorized Tyco Amp COPALUM contractor
• Colorado directory of aluminum wire repair electricians:
• Oklahoma: Oklahoma, Oklahoma City - True Tech Electric, (405) 802-8783 Midwest City, OK
• Texas directory of aluminum wire repair electricians:
• Dallas/Fort Worth: Slocum Electric COPALUM Certified Installer, Richard Palmer, General Manager/Owner, 972-438-7999, 972-438-9046-fax, Irving, TX, Richard@slocumelectric.com


• COPALUM-Certified Electricians & Aluminum Wiring Repair Products: contact us to add your free listing IF you are a qualified aluminum wire repair service company or product provider.

Note to AMP TYCO certified electricians: Electricians who perform aluminum wiring repair using the COPALUM Re termination Tool and are who are certified and trained in use of the AMP TYCO COPALUM connectors can be listed on this web page at no cost.

Use links at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

OTHER REPAIR PRODUCTS: for Aluminum Electrical Wiring - Ideal 65 Purple Twister and Other Aluminum Wire Products/Articles

• Ideal-65 Twister - this one doesn't work - purple twist-on connector sold for aluminum wire repair
• CPSC reiterates unsuitability of twist-on connectors (Including the Ideal No. 65) for repairing aluminum wiring in residences.
• Independent Tests indicate Ideal-65 Twist-on retrofit connector fails UL 486C Safety Standard despite UL-listing
• Ideal 65 "Twister" History of and Links to CPSC Documents about Purple Twist-on connector failures
• Ideal Industries, Inc., 1000 Park Ave, Sycamore IL 60178-994. 800-435-0705 U.S. or 800-527-9105 Canada ideal@wirenut.com
• Dr. Jesse Aronstein, "Evaluation of a Twist-on Connector for Aluminum Wire", Forty-Third IEEE Holm Conference on Electrical Contacts, Jan 1997, 0-7803-3968-1/97.
  [This article describes the Ideal Industries Ideal#65 purple "Twister" twist-on connector marketed as a repair/retrofit for residential aluminum wi ring. --DJF]
  Abstract: A new type of twist-on splicing component for use with aluminum and copper wire combinations is tested to determine initial resistance, performance in a zero-current environment test, performance in a heat-cycle test, and portion of current carried by the connector's steel spring. The splices tested consist of two aluminum wires and one copper wire. The aluminum wire samples used for the test are of the types actually installed in aluminum-wired homes. Initial resistance is found to be relatively high, and there is a significant sample-to-sample variation. This reflects failure to consistently establish low-resistance wire-to-wire contact through the insulating oxide film on the wire. Results of the environmental and heat-cycle tests show deterioration of a significant portion of the samples. The splices made with this connector are also found to be sensitive to mechanical disturbance, such as applied in normal installation when the completed splice is pushed back in to the junction box. Based on the test results, it is concluded that this connector has not overcome the fundamental deficiency of twist-on connectors for use with aluminum wire applications. Keywords: aluminum wire, connectors, twist-on connectors, environmental test, heat-cycle test.
• Southwire Corporation, manufacturer of aluminum (and other) wire products
• Consumer Product Safety Commission various information resources
• What Owners Need to Know About [Aluminum] Wiring Dangers, Sandra Fleishman, Washington Post, 3 July 2004 pF01

Contents -- More expert information on Aluminum Wiring

Use links at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

More Information on Aluminum Wiring Hazards and Other Building Diagnostic Inspections and Repairs

• The Aluminum Wiring Information Website Aluminum Wiring Hazards and Repairs: in-depth info, photos, documents. Main Page.
• The Aluminum Electrical Wiring Hazard Explained (in the document you are presently viewing)
• How to Reduce the Risk in Buildings with Aluminum Electrical Wiring - Overview of Acceptable Repair Practices (in the document you are presently viewing)
• Aluminum Electrical Repair Method Details - "How to" details, how to identify, COPALUM repair, alternative repairs, history, products, research, source of special AMP TYCO COPALUM connectors & COPALUM Electricians (in the document you are presently viewing)
• COPALUM Electricians: Sources of TYCO COPALUM -Certified/Trained Aluminum Wire Repair Services (in the document you are presently viewing)
• Other Products, Ideal 65 Purple Twister (not recommended), & other Aluminum Wire Products/Articles (in the document you are presently viewing)
• The Aluminum Wiring Bibliography: extensive resources on Aluminum Wiring
• Aluminum Wire Failure Reports & Photos: Real life aluminum wiring field failure reports
• Reducing the Fire Hazards in Aluminum-Wired Homes, Jess Aronstein, Ph.D., This document answers most technical questions about the hazards and remedies of aluminum electrical wiring. Some of the sections of this very thorough document are listed below:
• Fire Hazards With Aluminum to Copper Twist-on Connectors & Acceptable Aluminum Wiring Repair Practices Color Photos, Current Issues. 9/28/95 CPSC Meeting Minutes
• "Is YOUR Aluminum Wiring Safe?" article discussing safety claims made by some people without looking at the wiring, J. Aronstein, 11/21/95
• "Repairing Aluminum Wiring," U.S. Consumer Product Safety Commission Publication CPSC#516 available online
• * Safety Hazards and Safe Inspection Procedures for Electrical and Home Inspectors at Residential Electric Panels
• Electrical Panels, How to Inspect in Buildings, safety for electrical inspectors, electrical panel, fusing, wiring defects, defective products. Inspection Class Presentation
• Electrical System & Wiring Hazard Inspection, Detection, Cause, Remedy, Prevention - Main Electrical Page
• Aluminum wiring notes for home inspectors
• Directory of Home Inspectors accessible via Internet

InspectAPedia ^TM Home & Site Map - Building Inspection, Diagnosis, & Repair, Environmental Inspection & Testing - Research Website

Home Inspection Construction Consulting Services & advice for home buyers

Contact Daniel Friedman for website content suggestions or for fee-paid consulting

	Enter your search termsSubmit search form
	Search This Website - InspectAPedia.com

Website Kudos

• 12/1995 - PC Computing Magazine: Names this website as among the "Best 1001 Internet Sites." See the Engineering category, p. 146.
• Starting Point: named this website as a key Internet resource page as a Starting Point Hot Site

   Contents - Reducing the Fire Hazard in Aluminum-Wired Homes

Also See: The Aluminum Wiring Information Website Aluminum Wiring Hazards and Repairs

PREFACE to Reducing the Fire Hazard in Aluminum-Wired Homes

[Original printed copy page numbers have been retained. New reference-links point directly to online documents such as US CPSC Publication 516 and photographs of repair procedures.

This report is based on twenty years of investigation and testing of aluminum wire branch circuit connections. Included are investigations of in-home performance, burnouts, and fires, laboratory testing, and extensive review of industry and public agency test results and documents. The laboratory testing and investigations have been performed primarily for the U.S. Consumer Product Safety Commission (CPSC), for litigants and insurance interests with respect to fires which may be aluminum wire related, and for Canadian consumer groups, among others.

This report was first issued by Wright-Malta Corporation, which at the time had one of the largest aluminum branch circuit connection testing operations in the world. In 1982, there were approximately 7,500 aluminum and aluminum-copper connections on long-term test, plus (for comparison purposes) a substantial number of copper-wired connections. The results of the tests performed at Wright-Malta Corp. have been documented in reports written for CPSC and in published articles and technical papers. A partial listing is provided in Section 7, Bibliography.

In initiating this report, Wright-Malta Corporation did not represent any commercial interests. The company did not (and still does not) manufacture or market any of the products or services involved or any competitive products or services. Wright-Malta Corporation's aluminum wire testing activity was completed in the late 1980's, and the company has not been involved in this matter (including the revisions of this report) since that time.

This report is made available by the original author for homeowner, inspector, and trade information. The report reflects best information and test results available through the revision date.

Reducing the Fire Hazard in Aluminum-Wired Homes Sept. 12, 2000 p. 1

INTRODUCTION to Reducing the Fire Hazard in Aluminum-Wired Homes

A fundamental principle of electrical safety for wiring in buildings is that high temperatures are hazardous. While some protection is provided by electrical enclosures, the high temperature that can develop at failing branch circuit connections can lead to fire in many ways.[1]

Aluminum-wired connections in homes have been found to have a very high probability of overheating compared with copper-wired connections.[2][3][4] The aluminum-wired connections that fail tend to progressively deteriorate at a slow rate, and after many years can reach very high temperature while still remaining electrically functional in the circuits. A large number of connection burnouts have occurred in aluminum-wired homes. Many fires have resulted, some involving injury and death. Examples of overheating of two common types of aluminum wire connections are shown in Figures 1 and 2 (following page).

The probability of aluminum-wired connection overheating in a home varies considerably according to the types of connections, the installation methods used, and the circuit usage, along with many other factors. Without detailed knowledge of the installation in a particular home, it is not possible to provide specific advice on corrective measures.

The most certain corrective action for all cases would be to rewire the home with copper wire. This is expensive and impractical in most cases. A practical approximation to rewiring can be achieved by a method known as "pigtailing", using a specially-selected connector and installation method to splice a short length of solid copper wire to each aluminum wire end. The copper wire "pigtail" is then connected to the circuit breaker, light fixture, receptacle, dishwasher, or other termination. This method is only effective if the connections between the aluminum wires and the copper pigtails are extremely reliable. Pigtailing with some types of connectors, even though they might be presently listed by UL or certified by CSA for the application, can lead to increasing the hazard.[5][6] (See Figure 1.)

Other actions and partial repairs are less certain in effectiveness, but they still can substantially reduce the risk of fire due to aluminum wire connection overheating. Among the possibilities are replacing certain failure-prone types of devices and connections with others more compatible with the aluminum wire, and removing the ignitable materials from the vicinity of the connections. These actions can be accomplished at lower cost than rewiring or complete pigtailing, but with less reduction of the hazard. The homeowner has choices to make. The objective of this report is to present the choices with a relative ranking of fire risk reduction.

The corrective methods and fire preventative actions described in this report are based on the best information available at this time. The installation and repair information in this report is provided only for guidance in establishing specifications for contracted work, which must be done in accordance with applicable codes and regulations by qualified electricians.

Reducing the Fire Hazard in Aluminum-Wired Homes Sept. 12, 2000 p. 2

FIGURE 1 - The use of most types of twist-on connectors for pigtailing repairs can lead to hazardous results. This twist-on pigtailing connection (two #10 aluminum wires with one #12 copper wire, in a 20-amp circuit) remains electrically functional in the circuit, but becomes extremely hot whenever a significant amount of current flows. The heat has deteriorated the insulation on both the connector and the wires. A portion of the connector's spring (white overheated section of spring in photo) becomes red hot at current above 12 amps.

FIGURE 2 - An example of overheating of wire terminals on a receptacle. Enough heat was generated by current flowing through the aluminum wire connections to cause charring of the receptacle body and disintegration of the insulation that was on the wire. Note that the face of the receptacle, as the original homeowner would have seen it with the cover plate on, looks normal.

Reducing the Fire Hazard in Aluminum-Wired Homes Sept. 12, 2000 p. 3

ELECTRICAL SAFETY WARNING - regarding Reducing the Fire Hazard in Aluminum-Wired Homes

There is risk of property damage, injury, and death associated with working on the electrical system of a home. Shock, electrocution, and fire hazards are present. All work involving electrical components in the home wiring system should be done by persons trained and qualified for the job, with the power turned off at the main disconnect (main breaker, switch, or fuse block). Refer to appropriate industry and trade publications for safety precautions that should be taken.

Since the practical application of the information contained in this report is totally in the homeowner's or contractor's control, and the report's information can reduce but not eliminate the associated hazards, the author and/or provider of this report disclaim any responsibility or liability of any sort related to the information that it contains.

Reducing the Fire Hazard in Aluminum-Wired Homes Sept. 12, 2000 p. 4

1. REDUCING THE POSSIBILITY OF CONNECTION OVERHEATING at Aluminum Wiring Repair-Connections

A. USE OF ANTI-OXIDANT AND ABRASION - Aluminum Wiring Repair

To make the lowest resistance and most permanent connections to aluminum wire, the following procedure must be followed:

1) After stripping the insulation off the wire for the proper distance, using a stripping tool that does not nick the wire, coat the bare aluminum with Burndy "Penetrox A" compound. (Caution: some other "oxide inhibitor" compounds sold for the purpose are flammable. Penetrox A is not. Do not substitute.)

2) Abrade the surface of the aluminum wire, with the compound on it, with #240 grit "wet-or-dry" abrasive paper. Maintain the coating of compound while abrading.

3) Coat mating parts of the connector or terminal with the inhibitor compound.

4) After completing the connection, thoroughly clean off excess compound which is not inside the connection.

A detailed photo-illustrated description of this alternative repair procedure for pigtailing aluminum wiring, including careful use of non-flammable anti-oxidant is available at Special Aluminum Wire Repair Method using for twist-on splice w/aluminum

*** CAUTION - THESE REPAIRS MUST BE DONE BY A QUALIFIED ELECTRICIAN ***

Reducing the Fire Hazard in Aluminum-Wired Homes Sept. 12, 2000 p. 5

B. PIGTAILING USING AMP "COPALUM" CONNECTORS for Aluminum Wiring Repairs

The AMP "COPALUM" connector is applied using a special set of dies in a power-driven tool. After application of the connector, a heat-shrink insulator is applied. Solid copper wire "pigtails" spliced to the aluminum wire this way may be connected to receptacles, switches, circuit breakers, lamps, appliances, and all other terminations in the normal manner. (Note: all aluminum branch circuit wire terminations in the home must be treated this way for a complete and permanent repair, as the overheating problem involves all types of aluminum-wired connections.)

Repair by pigtailing using COPALUM connectors installed by a qualified electrician is the only method considered by CPSC to be a permanent repair. Their recommendation is based on extensive testing. The method is described in more detail, and sources for more information are provided in an article in Consumer Reports, January 1981.[7] While the application of COPALUM connectors is considered to be satisfactory without special preparation of the aluminum conductor, it is suggested that antioxidant compound and abrasion as per Section 1A (above) be used to provide an additional safety factor.

WARNING - Use of other types of crimp-on connections with aluminum branch circuit wire can be hazardous. Do not use commonly-available crimp connectors applied with a plier-like hand tool, even though they are often sold as applicable for "all wiring repairs", and in fact may be made by AMP (the same manufacturer that makes the "COPALUM" connector). If the AMP COPALUM connector (with its special tooling and qualified installer) is not locally available, see Section 1C, below.

Illustration of copper wire pigtails spliced to aluminum circuit wires using AMP Copalum connectors (Source: U.S. Consumer Product Safety Commission)

The US CPSC Publication 516 is available at Repairing Aluminum Wiring US Consumer Product Safety Commission Publication #516 where we have posted an on-line copy. This document is also available from the US CPSC and from the US Superintendent of Documents, Pueblo CO.

A photo-illustrated description of this procedure is available at The repair recommended by CPSC

*** CAUTION - THESE REPAIRS MUST BE DONE BY A QUALIFIED ELECTRICIAN ***

Reducing the Fire Hazard in Aluminum-Wired Homes Sept. 12, 2000 p. 6

C. PIGTAILING USING "Scotchlok" TWIST-ON CONNECTORS for Aluminum Wiring Repairs - an alternative repair method for aluminum wiring

Provided that special installation methods are used, 3M "Scotchlok" connectors are considered to be the best available alternative to the COPA