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Safe Electrical Inspection Procedures GFCIs and AFCIs for Home Inspectors
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• Safety considerations during the inspection or test of GFCIs - ground fault circuit interrupters
• Safety considerations during the inspection or test of AFCIs - arc fault circuit interrupters
• Electrical Inspection Safety procedures for home inspectors & electrical inspectors

This article discusses safety procedures for the electrical inspector, home inspector, or other professionals while examining GFCIs and AFCIs. Safe electrical inspection procedures and safe use of volt meters, DMMs, multimeters, and similar electrical test equipment is discussed at the end of the article.

© Copyright 2009 Daniel Friedman, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. 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.

These electrical inspection suggestions are not a complete inventory of all electrical safety procedures nor of all electrical components that should be inspected; these notes focus on identification of conditions that may present special electrical hazards for the electrical inspector. Contact Us by email to suggest changes, corrections, and additions to this material.

Inspecting and Testing Electrical Receptacles or "outlets" and GFCI-Protected Receptacles

Testing GFCIs on Un-Grounded Knob and Tube Electrical Circuits

1. No: the GFCI test device or internal GFCI test exercised by the test button depends on being able to produce a small internal current leak to ground. Since there is no electrical ground wire present, the test feature won't work.
2. Yes, sort-of: you could rig your own test of a GFCI device on a knob and tube or other un-grounded circuit by making a connection from the hot lead of the receptacle to a known ground such as a water pipe or radiator. We've demonstrated this procedure using a test instrument as well as a bare wire. DO NOT DO THIS unless you are specially trained and equipped to do so. It is dangerous for various reasons including the chance that you or a bystander will be killed by electric shock.

There have been some recalled GFCI devices that would not work reliably. If you had the bad luck to try your amateur test on one of these, the results could be a disaster. See SQUARE-D RECALLS.

Inspecting Arc Fault Circuit Interrupters - Safe Procedures

General Electrical Safety Suggestions describes important basic safety procedures, clothing, and equipment for home inspectors and electrical inspectors.

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SAFETY: ELECTRICAL INSPECTION SAFETY
  Shock Risk Statistics
  Outside Electrical Inspection
  Electric Meter & Service Entry
  Local Electrical Grounding
  Electrical Panel Interior Inspection
  Removing Electric Panel Covers
  Electrical Panel Cover Screws
  Electrical Panel Interior Hazards
  Testing Main Breakers or Fuses
  Inspect Breakers, Fuses, Circuits
  Testing Receptacles GFCIs AFCIs
  When to Shut Down Equipment
  Touching Electrical Equipment
  Guide to Electrical Test Equipment
  Using DMMs & VOMs Safely
  Voltage Measurement & Detection
  General Electrical Safety Suggestions
  Electrical Inspection Client Safety

Using an Electrical Receptacle Tester

Using a DMM or VOM to Check for Current

For example, if the meter indicates more than 1or 2 volts between a service panel cover and ground, there's a safety problem. Most low-cost analog-type meters such as the one described provide additional ranges used to read lower voltages with more sensitivity.

Some VOM models provide alligator clips for the ends of the test probes. These clips permit measuring high voltage without handling the probes. Always shut off the power before connecting the alligator clips.

Safe Use of Electrical Test Equipment: DMMs & VOMs

8.3 During an electrical system inspection the inspector is NOT required to
8.3.A. insert any tool, probe, or testing device inside the panels

How to Test digital volt meter DMM or Volt Ohm Meter VOM meter condition

These electrical inspection suggestions are not a complete inventory of all electrical components that should be inspected; these notes focus on identification of conditions that may present special electrical hazards for the electrical inspector. Contact Us by email to suggest changes, corrections, and additions to this material.

General Safety Suggestions for Electrical Inspectors

Pay attention, look carefully, move slowly before opening or exploring electrical equipment. Learn to recognize indications of a problem, such as but not limited to the examples in this article.

Do not assume anything when performing dangerous tasks such as inspecting electrical equipment.

• Do not assume that electrical power is "off" without confirming that using proper test equipment and methods
• Do not assume that system grounding is complete and correct
• Do not assume that all circuit breakers and GFCI's and AFCI's will work
• Do not assume that bystanders or clients won't move suddenly into the path of danger, or push you into it.

Do not touch live wires or connections. Watch your hands and other body parts. Handling live electrical wires without special training and equipment is highly questionable and often fatal.

December 12, 1988 - Madison, WI - Michael E. Hammes, 26, died in an apparent electrocution while working in Madison. Hammes had been hired by CUNA Mutual Insurance Society to change ballasts on fluorescent lights. Authorities said he was replacing a fixture in a fourth floor bathroom while standing on a stepladder when he slumped to the floor.

Hammes apparently was electrocuted when he touched live wire with one hand and a metal partition with his body or other hand, according to Dana County Coroner Ray Wosepka.

Hammes was a first-year electronics student. Wosepka said his investigation showed the light fixture had been properly wired. Hammes apparently replaced a ballast, a [transformer] that controls the electrical flow to the light bulbs, and was attaching the live wire when it electrocuted him, Wosepka said. -- Ibid.

If in your opinion unsafe conditions exist at a property you are inspecting you should notify all parties concerned, including building occupants/management/owners, realtors involved, and other appropriate authorities.

December 18, 1988 - Smyrna, GA - A Smyrna family's troubles with a faulty circuit breaker in their mobile home ended in tragedy when a fire broke out and killed 18-year-old Jeffrey Scott Auton. Auton's family, experiencing problems with the main circuit breaker, went to a home products store to buy a new one for their trailer, said Fire Investigator David Herndon.

The store did not have a circuit breaker to fit the family's needs and a new one had to be ordered. .... Herndon said the fire was started when the circuit breaker shut down completely as three space heaters were running. The family had a history of problems with the breaker, particularly from a load put on it by a large heating unit. Herndon stated that after the fire there was not a trace left of the circuit breaker; it was completely gone from the panel. -- Ibid.

For example, what if the case above had happened the day after the property described had been examined by an ASHI inspector? Were there perhaps clues which telegraph a developing problem? What about anecdotal reports from the occupants of recurrent breaker tripping, visible signs of overheating in the panel, widespread and unusual use of electric heaters, or evidence of work in the panel by untrained people? These risks to occupants are also a hazard to the inspector on several bases.

Protect yourself and your client from injury using but not limited to the suggestions we provide here and just below.

Electrical Inspection Safety Suggestions from Rex Cauldwell, a Master Electrician

OPINION-RC: "As a master electrician, here is how I teach opening a service panel in my seminars: "The lucky 7""

1. Eye protection: Wear safety glasses--electrical panels have been know to explode upon opening.
2. Insulating gloves: Wear rubber dishwashing gloves--panels have been known to become electrically hot as a screw falls when cover is removed.
3. Look before touching: Don't approach the panel until you give an overall look of the surrounding area to see if anything looks wrong--such as water on the floor under the panel.
4. Avoid Shock Pathways: Don't have any part of your body touching items adjacent to the panel.
5. Insulating floor pad: On a concrete or dirt floor, lay down a thick rubber Welcome mat and stand on it as you open the panel (wear rubber-soled shoes).
6. Insulating tools: Use insulated handle tools--I use a Milwaukee electric screwdriver.
7. Panel Door & Screws: Once door is open (in a Federal Pacific panel (and some other models) beware of falling trim and breakers that pop out), set door aside and don't lose the screws

-- Rex Cauldwell

Further Safety Warning--DF: these are helpful electrical safety suggestions from an experienced electrician. No list of suggestions is incomplete and these presume that they are being followed by an experienced, licensed electrician.

For example, there are almost certainly gloves and/or boots specifically recommended for this application; there are specific safety details to look at and for before touching an electrical panel, and procedures for using electrical test equipment to test or examine a suspect electrical panel.

Recommended books on electrical wiring:

Rex Cauldwell's Wiring A House - available online.

Rex Cauldwell's Safe Home Wiring Projects - available online

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Electrical Inspection Follow up and Client Safety

A home inspector or electrical inspector who has reported a very unsafe condition, recommended immediate action, and yet may later learn that occupants of the building were nearly killed by work by an incompetent repairman. [NOTE: Port Jervis, NY, AHS Ctl#4658911, 7/10/90.] What can be done to reduce the chance of this terrible consequence?

Recommending action on an unsafe condition can convert a pre-existing problem into an immediate catastrophe if the client or owner calls an untrained person to the property or if he attempts a do-it-yourself repair.

Often a referral to local fire inspector, electrical inspector, or utility company can help assure that repairs are prompt, proper, and safe. If you recommend immediate action for an unsafe condition, where possible you should provide some means for the client or building owner to assure that the action which is taken is proper and safe.

Inspectors are properly nervous and reluctant to prescribe the actual repair that is needed at a property - they may not know the detailed repair procedure, or there may be alternative repairs, or their description may prompt an un-trained person to try to do the work.

The Building Owner or Building Manager Needs to Know About Unsafe Conditions that Need Immediate Action

• What kind of trades person, utility worker, or other technician is proper to perform the necessary repair?
• What steps should be taken by the building owner or manager to assure that the repair is proper and safe?
• Is there an independent follow-up authority such as a fire inspector, utility company representative, or building code compliance inspector who should examine the repair?
• Are there well-known and common foul-ups in repair, or local inept repair companies against whom the owner should be warned?

The inspector should inform the appropriate parties both orally and in writing any suspected unsafe conditions.

If an area or component could not be fully inspected, the inspector should explain in writing why she or he did not enter or examine an area or component, and what additional inspections or steps should be taken, as well as the general risks that may be present.

Handling Immediate Threats to Life and Safety at a Building Inspection

If in the inspector's judgment equipment is an immediate threat to life and property, such as a boiler whose flue connection has fallen off, we recommend that dangerous equipment be shut down and the appropriate people notified. See Shutting Down Unsafe Equipment. In some cases "appropriate people" includes not only the client and building owner, but also building occupants.

In some instances such as sparking electrical panels, gas leaks, or evidence of a fire, the inspector and everyone else should leave the building immediately and from outside, call the fire department and as appropriate, the gas company, police, or rescue personnel.

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Technical Reviewers & References

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• Daniel Friedman - principal author/editor of the InspectAPedia^® Website
• Critique, contributions wanted: Contact Us to suggest corrections or additions to articles at this website, and if you wish, to receive online listing and credit as a contributor. Particular thanks are due to the many experts and also consumers who read and critique technical articles at InspectAPedia.com.
• Electrical shock injury statistics: www.healthatoz.com - September 2008;

  High-tension current generally causes the most serious injuries, although fatal electrocutions may occur with household current (eg, 110 V in the United States and Canada and 220 V in Europe, Australia, and Asia). Contact with alternating current at 60 cycles per second (the frequency used in most US household and commercial sources of electricity) may cause tetanic skeletal muscle contractions, preventing self-release from the source of the electricity and thereby leading to prolonged exposure. The repetitive frequency of alternating current also increases the likelihood of current flow through the heart during the relative refractory period (the "vulnerable period") of the cardiac cycle. This exposure can precipitate ventricular fibrillation (VF), which is analogous to the R-on-T phenomenon.-- circ.ahajournals.org - September 2008

• Thanks to Alan Carson and Bob Dunlop, Carson Dunlop, Associates, Toronto, for permission to use illustrations from their publication, The Illustrated Home which illustrates construction details and building components. Carson Dunlop provides home inspection education, publications, report writing materials, and home inspection services. Alan Carson is a past president of ASHI, the American Society of Home Inspectors.
• "Frequency of Occurrence and Sources of Rust and Corrosion in Electrical Panels," Daniel Friedman, IEEE HOLM Conference, Philadelphia PA, 1992 - see ELECTRIC PANEL RUST for an online version of this article.
• Jim Simmons: Personal communication, J. Simmons to Daniel Friedman, 9/19/2008. Photographs contributed to this website by Jim P. Simmons, Licensed Electrician, 360-705-4225 Mr. Electric, Licensed Master Electrician, Olympia, Washington Contact Jim P. Simmons, Licensed Master Electrician, Mr. Electric, 1320 Dayton Street SE
  Olympia, WA 98501, Ph 360-705-4225, Fx 360-705-0130 mrelectricoly@msn.com
• Kenneth Kruger: Original author of the sidebar on testing VOM DMM condition: Kenneth Kruger, R.A., P.E. AIA ASCE, is an ASHI Member and ASHI Director in Cambridge, MA. He provided basis for this article penned by DJ Friedman.
• "How to Use DMM's Safely," Leonard Ogden, CEE News, 888 Seventh Ave., New York, NY 10106, Dec 1990 p.10.
• Dr. Jess Aronstein, consulting engineer, Poughkeepsie NY, 1991 protune@aol.com
• Rex Cauldwell, master electrician and contributor to the Journal of Light Construction on electrical topics
• New York State Central Hudson Gas and Electric Company, G&E/1-2/85 consumer safety pamphlet
• American Society of Home Inspectors, ASHI Training Manual, Al Alk -[obsolete, and includes unsafe practices-DF]
• Critique, contributions wanted: Contact Us to suggest text changes and additions and, if you wish, to receive online listing and credit for that contribution.

More Information on Building Diagnostic Inspections and Repairs

• * 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 Panels, How to Inspect in Buildings, safety for electrical inspectors, electrical panel, fusing, wiring defects, defective products. Inspection Class Presentation
• Federal Pacific Electric (FPE) Stab-Lok Circuit Breaker Panel Hazards Website - Latent fire hazards, in-depth authoritative research, documents, advice on Stab-Lok electric panel and circuit breaker failures and what to do when this equipment is found in buildings.
• Lightning Strike Risk Assessment, Protection Systems & Services
• Multi-wire branch circuit inspection and defects
• Rust and Corrosion in Electrical Panels, A Study and Report on Frequency and Cause for Electrical and Home Inspectors at Residential Electric Panels
• "Electrical System Inspection Basics," Richard C. Wolcott, ASHI 8th Annual Education Conference, Boston 1985.
• "Simplified Electrical Wiring," Sears, Roebuck and Co., 15705 (F5428) Rev. 4-77 1977 [Lots of sketches of older-type service panels.]
• "How to plan and install electric wiring for homes, farms, garages, shops," Montgomery Ward Co., 83-850.
• "Electrical System Inspection Basics," Richard C. Wolcott, ASHI 8th Annual Education Conference, Boston 1985.
• "Simplified Electrical Wiring," Sears, Roebuck and Co., 15705 (F5428) Rev. 4-77 1977 [Lots of sketches of older-type service panels.]
• "How to plan and install electric wiring for homes, farms, garages, shops," Montgomery Ward Co., 83-850.
• "Home Wiring Inspection," Roswell W. Ard, Rodale's New Shelter, July/August, 1985 p. 35-40.
• "Evaluating Wiring in Older Minnesota Homes," Agricultural Extension Service, University of Minnesota, St. Paul, Minnesota 55108.
• "Electrical Systems," A Training Manual for Home Inspectors, Alfred L. Alk, American Society of Home Inspectors (ASHI), 1987, available from ASHI. [DF NOTE: I do NOT recommend this obsolete publication, though it was cited in the original Journal article as it contains unsafe inaccuracies]
• "Basic Housing Inspection," US DHEW, S352.75 U48, p.144, out of print, but is available in most state libraries.
• Electrical System & Wiring Hazard Inspection, Detection, Cause, Remedy, Prevention - Main Electrical Page

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