Electrical Safety Hazards and Safe Electrical Inspection Procedures for Electrical Inspectors & Home Inspectors
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The Electrical Panel Inspection for Water & Rust Begins Outside

8. System: Electrical Inspection Standards for Home Inspectors (ASHI and other Associations & State Regulations)
8.1.C. [The inspector shall observe] amperage and voltage ratings of the service

Inspection of the Electric Meter and Service Entry Cable

Pay special attention to water entry at the service entry cable, at the top of the electric meter enclosure, and at the wall penetration where the SEC enters the building as these conditions can send water into the electrical panel where corrosion creates unreliable equipment and water is a hazard.

• The frayed service entry cable (left) and lost wire-clamping seal around the service entry cable at the top of the electrical meter box (left) send wind-blown rain into the enclosure.
• The bottom of the electrical meter enclosure acts as a funnel to collect and send rainwater into the interior of the service entry cable where it is conducted as if in a plastic pipe, right into the top of the electrical panel located below this point inside the home. A photo later in this article shows the water entry tracking stains at the SEC in the main panel.
• Capillary action sends rainwater following the outside of a service entry cable right into the building if the cable is not sealed at the wall penetration (photo above right).

See ELECTRIC PANEL RUST for a study of water entry, rust, and corrosion in electrical panels presented at the 1992 IEEE Holm Conference.

See ELECTRIC METERS & METER BASES for procedures used for inspecting these outdoor components.

Inspect the Local Electrical Grounding Electrode or Grounding Connections

• Do not assume that the grounding electrode is a real one. Kick it. We find short scraps driven into the ground that can sometimes just be pushed over or pulled out, as our client is demonstrating. Often ground connections have come loose, were never connected, or have corroded away. The ground connection shown here is not reliable. The inspector has easily lifted the short ground rod out of the ground. (Photo above left)
• Do not assume that the utility company's ground (back at the pole) is connected and working. Sometimes that ground has been lost and only the local ground is present - a very dangerous condition. see Case History: Double Fault Leads to Loss of Power for an account of loss of both local ground and utility company ground at a property.
• Do not assume that water pipes form a good ground - original metal pipes extending into the soil may have been replaced with plastic. (Photo above right)
• Do not assume that grounding connections you see are actually secure and making good electrical contact.

Details about inspecting electrical grounding and definitions are at ELECTRICAL GROUND SYSTEM INSPECTION.

Safety Suggestions for Inspecting the Electrical Panel Interior

8.3.C. [The inspector is NOT required to] dismantle any electrical device or control other than to remove the covers of the main and auxiliary distribution panels.

How might the astute inspector spot trouble in an electrical panel cover before opening it?

At least one death, that of an electrician, has been reported to have occurred during the removal of a panel cover

Atlanta GA, a licensed electrician was opening the panel for inspection.] Apparently there was an incipient problem with the spring-loaded bus-bar assembly. When the cover was removed the bus assembly moved, an arc caused an electrical explosion, killing the inspector. -- J. Aronstein to D. Friedman, personal communication, 12/1991.

The following photos and text provide examples of external evidence that may let the inspector avoid trouble or a nasty surprise when inspecting electrical equipment.

Before touching the electrical panel the inspector should look for these conditions:

• Escape path: make sure that you know where you will turn and/or step back to retreat from the equipment if you discover a sudden and dangerous surprise (sparks, rats, bees, etc).
• Wet floors or other wet conditions:
  • Do not touch electrical equipment if you are standing on a wet surface.
  • Notice the cold water pipe condensation dripping onto and into the electrical panel in the left hand photo below

The pair of photographs below show two clear warnings that water has been entering an electrical panel - watch out for rust, and for circuit breakers that may not trip in response to an overcurrent, due to internal corrosion.

This defect is not one for which a home inspector (nor most electricians) can reliably test in a home, but the warning remains appropriate. Replace such breakers, and if the electrical panel is badly corroded the entire panel needs replacement.

See RUST in ELECTRICAL PANELS for a detailed account of the sources of water and rust in electrical panels and the frequency of observation of rust and water damage in that equipment.

Safety Procedures for Removing Electric Panel Covers: for Electrical Inspectors & Home Inspectors

ASHI Standards 8.1.B [The inspector shall observe] service equipment, grounding equipment, main overcurrent device, main and distribution panels.

Distance: Warn clients to remain at a safe distance. Assistance: Do not permit your client to assist you in removing or installing the panel cover. Only one person should be touching electrical components at any time. The author asks clients to stand a little back while removing the cover, which makes it easier to remain in a blocking position (below). We might inform the client that opening the panel is a dangerous step, and that if sparks fly the client should not touch the inspector - though other parties present at the inspection might want to kick the inspector or take similar measures if necessary.

Electrical Panel Cover Fastener Screws & Electrical Meter Box Mounting Screw Hazards

• Looking: Look carefully for evidence of burning, arcing, or other damage before touching or moving components. Eg.: sharp sheet metal screws in panel covers may short hot wires.

Unsafe Electrical Panel Screws: the electrical panel cover screws have been replaced with sharp pointed sheet metal screws Electrical Panel Access, Rats & Other Distractions: (distractions from being careful) there are rats at your feet, or there is a rats nest of wires or other obstruction to safe cover removal - watch what you say. At an inspection the author had encouraged a nervous buyer to accompany him into an ugly dark muddy basement to inspect the mechanical systems. The client, a woman not properly dressed for an inspection, wore high heels and a tight skirt. She was wobbling in the dirt floor in a dark crowded corner of the basement, terrified and already shaking in the dim light. The author, encountering a maze of wires in the way of the electrical panel, forgot to edit his thoughts, and muttered aloud: "geez what a rats nest." The client screamed "RATS!!!" and ran terrified from the basement, falling towards the dark stairs. Distractions during an electrical inspection are themselves dangerous. A NE ASHI inspector reported that As I just touched an electrical panel cover screw with my Milwaukee screwdriver I saw a tremendous flash of light - as bright as the sun. I was certain I was dead. As moments passed I realized I was still standing there, alive. Am I alive? I asked myself. I learned that from behind me and my client, the real estate agent had chosen that moment to take a flash photograph of the proceedings. - to DF Randolph MA 09/2008 This distraction is more risky than it may appear. A sudden flash, a sudden shout or movement, could cause an inspector to lurch, touching an electrically live and dangerous component. It is important for the inspector to learn and practice calm, steady movements and to resist distractions.

How to Look for Unsafe Panel Cover Screws & for Evidence of Burning and Arcing When Approaching the Electrical Panel

• Look at the electrical panel before touching the electrical panel cover; is there evidence of a problem such as
• Arcing, Overheating or Burnups: you see evidence of electrical failures such as burned or overheated components. In the photo at left the ground wires are clearly overheated - something is wrong. In this case a homeowner was badly shocked when he touched his metal workbench. see Case History:Loss of Neutral Shocks Homeowner for details.

The pair of photos just below shows at left, electrical arc flashover soot, and at right, the repair - tape on the electrical wire, but the wire is still too close to the screw mounting hole for the panel cover.

• Look for improper and unsafe electrical cover screws, sharp pointed sheet metal screws, and look for electrical cables that pass too close to the screw openings in the electrical panel.

Now that we have removed the cover and carefully set the cover and screws aside (don't lose the screws),

What to Look for Inside the Electrical Panel as Immediate Safety Concerns to the Inspector

• Evidence of water entry inside the electrical panel (photo at below right) means that circuit breakers may be corroded and won't trip, connections may be unreliable, neutral or ground connections may be lost, and touching the equipment could be dangerous.
• Evidence of overheating, melting, burnups inside the electrical panel (photo at below left) - this was the ground that overheated when there was no neutral connection in the sub panel and neutral and ground buses were improperly bonded.

• Evidence of missing bonding or improper bonding (such as ground to neutral in a sub panel) may combine with evidence of overheating (photo above left) to indicate improper wiring, damaged equipment, and unsafe conditions.
  
  The loss of net ural in a garage sub panel (the steel screw bound in the aluminum neutral lug in photo at below right) combined with improper bonding (ground to neutral - red wire in photo at below left) and other conditions to shock an owner when he touched his metal workbench. see Case History:Loss of Neutral Shocks Homeowner for details of this case.

• Evidence of burned or overheated wires or damaged circuit breakers, aluminum wiring, faulty equipment, mis-wiring, linking, bus and bonding defects, and many other defects form part of the electrical panel inspection and are described outside of this safety procedures article - see ELECTRIC PANEL INSPECTION

Testing Main Circuit Breakers or Main Fuses in Electrical Panels

8.3.B. [The inspector is NOT required to] test or operate any overcurrent device except Ground Fault Circuit Interrupters

I continued to put my arm behind my back and close the breaker with my left hand with my head turned to the left.

BAM, a light as bright as the sun and an explosion. This knocked us down and blinded us.

We were rushed to the hospital. I spent the night in the ER with an ICU nurse and was off of work for 3 weeks and have had to have a stronger prescription. These FPE panels are all over the building

More Reading:
Electrical Panels, How to Inspect in buildings, safety for electrical inspectors, electrical panel, fusing, wiring defects,

Safety Procedures When Inspecting Branch Circuit Conductors, Breakers,Fuses, &c.

8.1.D. [The inspector shall observe] branch circuit conductors, their overcurrent devices, and the compatibility of their ampacities and voltages

In addition to examining the electrical panel before touching it, looking for dangerous conditions like water, rust, sheet metal screws, rats, and blocking client access, the inspector should also recognize that certain brands or models of electrical equipment are known to be unsafe and may be dangerous to inspect or operate.

Federal Pacific Electric Stab-Lok equipment includes breakers which remain internally "on" when switched "off", as well as too often failing to trip off in response to an overcurrent, and which have been reported to result in electrical arc explosions when manually or otherwise exercised.

Zinsco: Similar bus burnups and electrical arc explosions have been reported regarding Sylvania/Zinsco electrical panels.

Contact Us by email to add field reports of problems regarding these or other electrical products.

Inspecting Electrical Branch Circuit Wiring

Safety Procedures When Inspecting Electrical Outlets, Switches, Lights

8.1.E. [The inspector shall observe] the operation of a representative number of installed lighting fixtures, switches, and receptacles located inside the house, garage, and on its exterior walls

Before operating a switch or device perform a visual inspection for damage, looseness, burning or arcing, or heat. Devices missing cover plates are unsafe and risk both shock and fire. Metal cover plates also add shock risks. Watch out about turning on switches found off in the service panel. A circuit found in the off position may be that way due to an unsafe condition or a repair in progress. Leave it off and document the finding. The property owner should be consulted for permission before turning on any electrical device which has been found shut down. The light shown in our photo is a fire hazard and needs to be moved or replaced with an enclosed florescent fixture.

Also be careful about turning off switches found on. You may damage a computer data base, turn off a heart-lung machine, reset an alarm system, or turn off a marginal switch for the heat that leaves the property with no heat in freezing weather. Be safe and avoid disputes.

An example of accidentally switching off circuits in a building occurs often during removal of an awkward electrical panel cover - it's easy to accidentally push one or more circuit breakers into their off position during cover removal or replacement.

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

AFCIs: The requirement to inspect and test AFCIs is already in some regulations for home inspectors. It seems likely that remaining home inspection associations and state or provincial inspection standards-writers will soon update their electrical inspection standards section to address the new requirement for AFCI's. See AFCIs ARC FAULT CIRCUIT INTERRUPTERS for details of the electrical code changes regarding the requirement for arc fault interrupters in homes.

AFCIs can be properly tested only by using the test button on the device itself. External tool tests are incomplete and therefore unreliable.

When to Shut Down Unsafe Electrical Equipment

Some inspectors, with adequate training, exceed the requirements of the standards and will actually shut down extremely dangerous equipment themselves.

Be warned that whether you touch a building component or not there are grave responsibilities.

Touching a building component: if you precipitate a catastrophe, will of course be viewed as a mistake.

Not touching a building component: Failing to act effectively to protect occupants of a building you inspect will, of course, also be viewed as a mistake. If you failed to inspect, detect, report a hazard in a building you may bear liability if later an event occurs.

Disclaimers: A simple disclaimer "not inspected" is in adequate. An adequate disclaimer that meets ASHI standards makes sure that the client understands the significance of an observation [or of steps to omit making an observation].

The last man in rule: Trade and professional education classes concerning mechanical systems, which can involve life-safety concerns, commonly teach the "last man in" rule. Home inspectors know this problem as well. The last "expert" to set foot on the property is vulnerable to blame for any ensuing failures, even if s/he acted entirely correctly and even if s/he never touched the component later in question.

During an electrical inspection, it's your judgment call. Document your judgment.

In the final analysis then, the precise safety steps to be taken are up to the judgment of the inspector at the scene. The inspector should also document his or her action. Failing to do anything and failing to even serve notice may be viewed as very dangerous and seriously irresponsible.

With proper training, knowledge, and procedures, electrical inspections can be done safely and accurately. Be careful.

Touching Electrical Equipment During an Inspection?

• Never touch metal plumbing or gas system pipes while you're working around electricity.
• Never touch electrical equipment while standing on a damp or wet surface. [Unless you are trained and are wearing appropriate protective gear.]

Shocked homeowner: During an inspection an ASHI inspector warned the home owner that there was a short in a florescent ceiling light fixture. The owner, a contractor who had done his own electrical work, irritated and incredulous at this supposed defect, licked his knuckles and bridged a small space between the light body and a nearby gas pipe. He's now a believer. [NOTE: DJF home inspection, Beacon, NY 1990]

Amazing Alk: A very questionable procedure is suggested in The ASHI Training Manual [NOTE: "Electrical Systems," ASHI Training Manual, chapter by Alfred L. Alk, p. 18. ASHI 1987] indicating that the inspector can "test" to see if a panel is dangerously "live" (has an internal short) by tapping the box with the knuckles of his/her right hand to check for current, then laying the right palm on the box to feel for heat before beginning to remove the cover. DO NOT RELY ON THESE UNSAFE METHODS.

From a safety view, this is a bad idea. Never rely on physical touch to judge electrical safety of a component.

Details about the hazards of touching electrical equipment and alternative advice for determining whether or not equipment is safe to inspect are provided at Touching Electrical Equipment.

Also see  Guide to Electrical Test Equipment and  Using DMMs & VOMs Safely as well as  General Electrical Safety Suggestions for electrical inspectors.

Guide to Using Electrical System Test Equipment to Check System Safety

First use your head:

Stop, look, listen before touching. More on "just looking" is provided when we discuss opening the electrical panel. Do not rely on touch to determine if electrical equipment is safe. Details about the hazards of touching electrical equipment and alternative advice for determining whether or not equipment is safe to inspect are provided at Touching Electrical Equipment.

Using a Tic Tracer to Test for Presence of Voltage

Using a Neon Tester

Using an Electrical Receptacle Tester

Neither of these neat little electrical test tools can be relied on to report low levels of current leakage.

At an investigation of a garage roof that shocked a crew of builders during reconstruction after a lightning strike, we measured voltage varying between about 38 volts AC and 68 volts AC between some framing components and the earth. We could not detect these conditions with a neon tester. A VOM or DMM was needed.

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

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.

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

• InspectAPedia.com^® - Daniel Friedman - Publisher & Editor.
• 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 (e.g., 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

• Carson, Dunlop & Associates Ltd., 120 Carlton Street Suite 407, Toronto ON M5A 4K2. (416) 964-9415 1-800-268-7070 info@carsondunlop.com. Thanks to Alan Carson and Bob Dunlop, for permission to use illustrations from their publication, The Illustrated Home which illustrates construction details and building components. Carson Dunlop provides home inspection education including the ASHI-adopted Home Inspection Training Program (home study course), publications such as the Home Reference Book, report writing materials including the Horizon report writer, 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 mrelectricwa@gmail.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]

Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair

• Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.
• Recommended books on electrical inspection, electrical wiring, electrical problem diagnosis, and electrical repair can be found in the Electrical Books section of the InspectAPedia Bookstore. (courtesy of Amazon.com)
• * 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
• ...