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We recommend that residential FPE Stab-Lok electrical panels be replaced entirely or the entire panel bus assembly be replaced entirely, regardless of model number or year of manufacture. We recommend against replacing individual FPE Stab-lok circuit breakers. We do not sell circuit breakers nor any other products.

This document explains the latent electric shock and fire hazards associated with Federal Pacific Electric Stab-Lok electric panels and circuit breakers. Federal Pacific Electric "Stab-Lok" service panels and breakers are dangerous and can fail, leading to electrical fires. The problem is that some 240-Volt FPE circuit breakers and possibly also some 120-Volt units simply may not work. Readers of this document should also see FPE FIRES: Failure Reports and The Federal Pacific Stab-Lok Electric Panel Hazard Website. © 2009 Daniel Friedman, All Rights Reserved.

No part of this article may be reproduced electronically or at websites - use is reserved to the author. Printed copies of this material may be made and distributed provided that it is not sold nor used to sell or endorse other products, and provided the original source website is prominently displayed.

How Many FPE Stab-Loks Are There? Why Are They Still In Place?

It has been suggested that there are as many as 28 million of these FPE Stab-Lok breakers in use in the U.S. which means that in some conditions as many as one million of them may fail to provide proper fire protection. This includes "new old stock" and appears to include "substitute" FPE stab-lok circuit breakers, none of which have shown an improvement in reliability in independent testing. So the right "repair" is to replace the FPE Stab-Lok electric panel.

But where are they? Most homeowners whose houses are served by these panels are unaware of the hazards. So too are some inspectors and contractors. Because most homeowners do not order periodic electrical safety inspections, the presence of these panels is often undiscovered until an inspection made in the course of renovating or selling a property. Our field experience indicates that even when problems occur with this equipment, often it is simply removed or replaced with little publicity. Neither manufacturers nor some electricians are inclined to frighten consumers.

See How to Identify FPE Federal Pacific Stab-Lok Electric Panels - is yours one of these? ALSO: A History of the FPE Stab-Lok Issue. But come back and finish this article too!

What is the FPE Stab-Lok Failure Rate and How Much Worse Is It Than Other Equipment?

FPE Stab-Lok or Federal Pacific Electric Stab-lok circuit breakers can fail to trip at an alarming rate. In the original testing, at a modest overload (135% of rating) switches that had never been touched (never mechanically switched) were energized on both poles. These failed 25% of the time, followed by a lockup that meant the switch would never trip in the future at any overload. Once these switches had been flipped on and off (mechanically energized), failures increased to 36%!

Worse, when individual poles on these switches were energized under the same conditions, 51% of the "virgin" switches failed, and for switches that had been mechanically energized, a whopping 65% of them failed!1

In the most recent independent tests of FPE Stab-Lok equipment, using a larger pool of FPE Stab-Lok circuit breakers than the older CPSC and Wright Malta tests found significantly higher failure rates of FPE Stab-Lok circuit breakers, including a look at critical safety failures (breaker failed to trip at 200% of rated current or jammed) which found up to 80% failure rate for FPE Stab-Lok GFCI circuit breakers (n=4), 12% failure rate for double pole FPE Stab-Lok circuit breakers (n=120), and a 1% failure rate for FPE Stab-Lok single pole circuit breakers (n=345). (To download this article see "Technical Reports" below.)

When a circuit breaker will not trip in response to an overload there is a serious risk of fire.

What is the Proper Repair for FPE Stab-Lok Panels and Circuit Breakers?

Homeowners and renovators who encounter these panels should replace the entire panel and circuit breaker set with new equipment. Panel replacement, can involve significant expense, typically $800 to $1200 depending on service size and other factors.

Do not simply replace individual FPE Stab-Lok circuit breakers: first of all, there is no data suggesting that new stock, replacement FPE breakers, or "new old stock" FPE breakers found in storage somewhere perform any better than the ones already in the FPE Stab-lok panel. Second, there are other functional and safety concerns in the panel besides the breakers themselves. We've seen panel bus damage, panel bus meltdowns, and failure of breakers to remain secured in or onto the connecting bus itself.

Replacement Federal Pacific Electric FPE Stab-Lok Circuit Breakers

For several reasons I do not recommend attempting to "repair" an individual failed Stab-lok breaker by buying a replacement either from used stock, new stock, or "compatible" stock:

• The replacement equipment and parts for FPE Stab-lok panels has not been independently tested and demonstrated to perform any better than the original materials
• Engineers involved in FPE Stab lok research have explained that a good part of the source of product failure for FPE Stab-Loks was in the original design and its specifications. It appears that while there were some "on the fly" (and unapproved) changes from time to time on the manufacturing line for this product, there was never a redesign suitable to attempt to "design out" the product failure. One expert opined to me privately that he believed that the original product's price point in the electrical equipment market was at the low end, and that had Federal Pacific attempted a redesign they'd not have had a product they could sell at their price point.
• There are other hazards in FPE electrical panels besides the breakers, including bus and bus insulation meltdowns and shorts.

A few other warnings:

• "Exercising" the FPE stablok circuit breakers by turning them on and off has not been shown to "un-stick" or in any other manner improve the probability of working properly, and conversely, such activity may in fact increase the chances of a future failure
• "Testing" FPE circuit breakers by applying a load may give an instantaneous picture of the performance of individual breakers but it does not predict their performance when a real safety problem occurs (overcurrent) later. More important, except if performed by a very expert person, in-place testing is very dangerous, risking fires in the building being tested.

In sum, if you could replace all the FPE Stab-Lok equipment with (somehow magically obtained) all "new" FPE Stab-Lok equipment (found in a used-or new-old-stock warehouse for example) the risk level for the building would not be sufficiently different from before the replacement and would remain high: there remains a latent risk of fire from failure of these breakers to trip in response to overcurrent.

Replacement Federal Pacific Electric FPE Stab-Lok Panels is Recommended

For some cost and method alternatives when replacing an Federal Pacific Electric Stab-Lok Panel or "load center" see REPLACEMENT PANELS which describes conventional Option#1 - "remove and replace" the electrical panel and Option#2 - FPE Load Center Replacement using Cutler Hammer (CH) Adjustable Retrofit Kit

See FPE REPLACEMENT BREAKERS for details about and advice against replacement circuit breakers sold for retrofit or installation into Federal Pacific Electric Stab-Lok electrical panels.

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• Additional technical contributors & reference sources for this article are listed below.

Use links just below or 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.

FPE Stab-Lok HAZARDS & REPAIRS WEBSITE
SUMMARY OF the FPE Stab-Lok PROBLEM
FPE HAZARD ARTICLES, STUDIES
FPE Stab-Lok TECHNICAL REPORT
HOW TO IDENTIFY FPE & FP
REPORTS OF FPE FAILURES
HOW TO REPORT FPE INCIDENTS
FPE REPAIR ELECTRICIANS
FPE REPLACEMENT BREAKERS
FPE REPLACEMENT PANELS
FPE REPLACEMENT PANEL COSTS
CAN'T AFFORD A NEW ELECTRIC PANEL?
FEDERAL PIONEER in CANADA
FIRES WAITING TO HAPPEN
  How Many Stab-Loks
  Stab-Lok Failure Rate
  Proper Repair
  Proving the Hazard
  Multiwire Circuits
  Single Pole Breakers
  Latent Safety Hazard
  Failure Reports
  Technical Reports
FPE HISTORY
ADVICE TO HOME BUYERS w/ FPE PANELS
HOME INSPECTION LANGUAGE for FPE Stab-Lok
IAEI LETTER

More Reading:
Federal Pacific Electric (FPE) Panel Fire and Failure Photos
Federal Pacific Electric (FPE) Panel Fires and other Failures: Anecdotal Field Reports

• Dan Friedman is a building consultant in Poughkeepsie, NY. He served as chairman of both the Education Committee and the national Technical Committee of the American Society of Home Inspectors. For Content Suggestions, Contact information is at his website. Because of website traffic volume, if you are seeking contact to ask a technical question, please handle it by email, not telephone.
• Rex Cauldwell: "Safe Wiring Practice," Rex Cauldwell, Journal of Light Construction, letter March 1995, p.6.
• Note: as we didn't add this reviewers list until 2007, this list of technical reviewers is incomplete; we have received comments and suggestions regarding this topic, edits and remarks included, from engineers and management from the US CPSC, electricians (many listed at our page on field reports of FPE failures), home inspectors, licensed electricians, and electrical engineers, and even a few attorneys and real estate agents, since 1986. Technical review, critique, content suggestions, questions, or clarifications are invited and where a contributor wishes, credit and links will be provided to that source. Contact us to provide feedback.
• Dr. Jess Aronstein, electrical engineer, Poughkeepsie, NY, forensic engineering services, independent laboratory testing for various agencies
• Alan Carson, Carson Dunlop Associates, Toronto, Ontario. Mr. Carson is a home inspection professional, educator, researcher, writer, and a principal of Carson Dunlop Associates, a Toronto home inspection and education firm. Mr. Carson is a past president of ASHI, the American Society of Home Inspectors
• Mark Cramer Inspection Services Mark Cramer, Tampa Florida, Mr. Cramer is a past president of ASHI, the American Society of Home Inspectors and is a Florida home inspector and home inspection educator.
• Carl Grasso, Esq., Herzfeld & Rubin, New York, NY. Mr. Grasso is an attorney who managed a plaintiff's class action litigation against Federal Pacific Electric in New Jersey.
• William King, US CPSC Director of Electrical Engineering (Ret).
• Licensed Electricians: FPE Fire and Failure Reports includes electricians who have provided cases and photographs of field failures of FPE equipment at this website.
• Homeowners, Home Inspectors, Electricians: Federal Pacific Electric (FPE) Panel Fires and other Failures includes anecdotal field reports provided by a range of contributors including electricians (and some home owners or home inspectors) who have provided cases and photographs of field failures of FPE equipment at this website.

More Information on Building Diagnostic Inspections and Repairs

• The Federal Pacific Stab-Lok Electric Panel Hazard Website Safety Information for Consumers. 2009
• Home Inspection Reporting Language and discussion for FPE panels
• How to Identify FPE Federal Pacific Stab-Lok Electric Panels - is yours one of these? ALSO: A History of the FPE Stab-Lok Issue.
• FPE FIRES: Failures continue: FPE breaker fails, results in fires: field reports
• Federal Pacific Electric Fires Waiting to Happen, Debate Waiting to Be Ended, detailed article
• Replacement Circuit Breakers for FPE Stab-Lok Electric Panels? are not recommended. We recommend replacement of the entire electrical panel, or replacement of the entire electrical panel bus assembly. See FPE REPLACEMENT PANELS for details.
• Replacement Panels for FPE Stab-Lok load centers - options include conventional complete panel replacement and a less costly replacement of the panel interior load center/bus assembly
• * Safety Hazards and Safe Inspection Procedures for Electrical and Home Inspectors at Residential Electric Panels
• Aluminum Wiring Information Website Aluminum Electrical Wiring Hazards and Repairs: in-depth authoritative info, photos, documents including selection of proper vs. ineffective repair methods. E.g.: Ideal 65 "Twister" purple connector fails in field and lab testing with aluminum wire.
• Ampacity of an Electrical Service: How to determine the electrical service size or ampacity entering a building
• Circuit Breaker, a bad one fails to trip failure at aluminum bus-to-circuit breaker connection - field report and photographs
• Electrical System & Wiring Hazard Inspection, Detection, Cause, Remedy, Prevention - Main Electrical Page
• Electrical Panels, How to Inspect in Buildings, safety for electrical inspectors, electrical panel, fusing, wiring defects, defective products. Inspection Class Presentation
• Lightning Strike Risk Assessment, Protection Systems & Services
• Multi-wire branch circuit inspection and defects


• Directory of Home Inspectors accessible via internet


• Carson Dunlop's Home Inspector's Home Study Course (DJF is a contributor and participant in this education project).

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