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 Touching Electrical Equipment - Safety Hazards and Electrical Inspection Procedures
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Hazards of touching electrical equipment - safety procedures: this article reviews safe and unsafe methods for touching or not-touching electrical equipment during its inspection. Warning: photographs in the article below include one of a gruesome death by electrocution. Electrical safety is an important consideration for both workers and building owners/occupants, and the hazards are real. This is chapter of our article on electrical safety procedures which discusses safety hazards at residential electrical panels and suggests safety procedures for the electrical inspector, home inspector, or other professionals who examine residential electrical systems. Also see SAFETY: ELECTRICAL INSPECTION SAFETY.
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman.
Dangers of touching electrical equipment during an inspection
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.
Original text: DF, as ASHI Technical Journal Staff, January 1992, with updates February 2006.
Watch out: See SAFETY: ELECTRICAL INSPECTION SAFETY. 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.
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]
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. Don't do this!
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From a safety view, this is a bad idea. Never rely on physical
touch to judge electrical safety of a component. Use instruments.
Test instruments such as the VOM described above, and the
TIFTM Tic Tracer shown at left are inexpensive, effective,
safer when used properly.
NOTE: Alexandra Radkewycz, a Canadian researcher,
reports severely shocking experiences from failure to make proper
use of instruments. [Private communication to author, 12/91.]
We describe the TIF Tic Tracer in detail, including providing examples of its use, at VOLTS / AMPS MEASUREMENT EQUIP. |
Electrocution Hazards from Touching Electrical Equipment
 The gruesome death by electrocution shown in the photograph at page top occurred when the man shown tried to steal electrical power from a high voltage cable. - Jim Simmons
- 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 Albert Alk: A very questionable procedure is suggested in The ASHI Training
Manual [ "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.
Watch out: DO NOT RELY ON THESE UNSAFE METHODS.
Babbling Bob Smith: an electrician asked to lecture to home inspectors at a conference we organized advised that home inspectors should check the security of the incoming mains connections at the electrical panel by grabbing the wires and giving them a good shake and pull. His advice was so mistaken that we were forced to interrupt the lecture to exclaim and issue a warning.
Watch out: DO NOT DO THIS. While an experienced electrician, wearing proper safety equipment, will in some circumstances have to touch or hold live electrical wires, there is risk of death by electrocution. This wire grabbing and shaking is not something that a home inspector or home owner should ever attempt.
From a safety view, these are bad ideas that can kill someone. Never rely on physical
touch to judge electrical safety of a component.
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Use electrical test instruments to check for live voltage. Test instruments such as the VOM described above, and the
TIFTM Tic Tracer (above), and the contact and "touchless" pens (photo at left) and tools used to detect the presence of voltage are inexpensive, effective,
safer when used properly.
[Alexandra Radkewycz, a Canadian researcher,
reports severely shocking experiences from failure to make proper
use of instruments. Private communication to author, 12/91.]
See VOLTS / AMPS MEASUREMENT EQUIP for a description of tools used to detect the presence of live electrical wires & devices and for the measurement of actual volts or amps. See Using DMMs & VOMs Safely for details about using test equipment during an electrical inspection. |
In the same ASHI Training Manual chapter the author, Al Alk, offers another more accepted suggestion: "Inspectors should practice working around open enclosures with the left hand behind the back.
If the right hand receives a shock the current will more likely pass down the right half of the body: the heart is on the left side. Inspectors
who wear rings must be especially wary when working near an open box." [NOTE: ASHI Training Manual, Op. Cit.- Obsolete]
Grounding: A basic rule for working around electrical equipment: if you are yourself not grounded, and if you only touch one
single component at a time, risks are reduced. Never ground yourself through your feet. Don't stand on a wet floor. If it's necessary to
touch electrical components in such a location, a trained electrical worker uses a dry ungrounded platform such as boards or a wooden ladder.
Rings and watches: When working around electrical equipment, first remove rings and watches to reduce the risk of electric shock. At an IBM test site in Poughkeepsie,
NY in the 1980's a test technician was killed while working on a computer. His metal watch band contacted a live component while other body parts
were touching a grounded component, possibly the steel frame of the assembly. Similar accidents around electric panels are a real risk for home inspectors.
Electric Panel cover screws: if you find that a sharp-tipped sheet metal screw
has been used (usually to replace a lost original fastener) you should
be alert for pierced, damaged, short-circuited wires in the panel
- both during removal and during panel cover replacement. We will
not reinstall a sharp-pointed screw in a panel cover if wires are
crowded close to the screw opening. Having seen more than one shorted
and burned panel from precisely this cause, we warn clients about
this unsafe detail. It is trivial to correct.
Never Assume You've Turned Power Off - Use a Neon Tester, Voltage Detector, or Multimeter
 The most basic electrical safety procedure I can think of when working on electrical devices or electrical wiring involves knowing how to:
- turn off power to the device or circuit or system where you're planning to work
- make sure that power is really OFF there
I never touch something electrical that I've "turned off" without using at least a neon tester to or a voltage detection pen to see that electrical power is really off.
In 1970 I turned off power to a junction box to fix a light - the light went out - so I figured that all electrical power to the junction box was really off.
Then while wiggling wires in the junction box I got a huge spark and a little shock.
Some nitwit had run two different live circuits into the same junction box.
Now I'm more careful. I figure that if you don't electrocute yourself, the rest is easy - you can always run out of a burning building. Well really inspectors have more responsibility than that: in addition to not killing yourself, you must protect the safety of your clients and of the occupants of buildings on which you've performed work.
VOLTAGE MEASUREMENT EQUIPMENT describes voltage sensors, DMMs, VOMs, and other choices of equipment we use for testing electrical circuits and for performing basic electrical or appliance wiring repairs.
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Technical Reviewers & References
Related Topics, found near the top of this page suggest articles closely related to this one.
- 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
- 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. Mr. Cramer serves on the ASHI Home Inspection Standards. Contact Mark Cramer at: 727-595-4211 mark@BestTampaInspector.com
- John Cranor is an ASHI member and a home inspector (The House Whisperer) is located in Glen Allen, VA 23060. He is also a contributor to InspectApedia.com in several technical areas such as plumbing and appliances (dryer vents). Contact Mr. Cranor at 804-747-7747 or by Email: johncranor@verizon.net
 Carson, Dunlop & Associates Ltd., 120 Carlton Street Suite 407, Toronto ON M5A 4K2. (416) 964-9415 1-800-268-7070 info@carsondunlop.com. The firm provides professional home inspection services & home inspection education & publications. Alan Carson is a past president of ASHI, the American Society of Home Inspectors. Thanks to Alan Carson and Bob Dunlop, for permission for InspectAPedia to use text excerpts from The Home Reference Book & illustrations from The Illustrated Home. Carson Dunlop Associates' provides:
- Commercial Building Inspection Courses - protocol ASTM Standard E 2018-08 for Property Condition Assessments
- Home Inspection Education Courses including home study & live classes at eleven colleges & universities.
- Home Inspection Education Home Study Courses - ASHI@Home Training 10-course program.
Special Offer: Carson Dunlop Associates offers InspectAPedia readers in the U.S.A. a 5% discount on these courses: Enter INSPECTAHITP in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
- The Home Reference Book, a reference & inspection report product for building owners & inspectors.
Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
- The Home Reference eBook, an electronic version for PCs, the iPad, iPhone, & Android smart phones.
Special Offer: For a 5% discount on any number of copies of the Home Reference eBook purchased as a single order. Enter inspectaehrb in the order payment page "Promo/Redemption" space.
- The Illustrated Home illustrates construction details and building components, a reference for owners & inspectors.
Special Offer: For a 5% discount on any number of copies of the Illustrated Home purchased as a single order Enter INSPECTAILL in the order payment page "Promo/Redemption" space.
- The Horizon Software System manages business operations,scheduling, & inspection report writing using Carson Dunlop's knowledge base & color images. The Horizon system runs on always-available cloud-based software for office computers, laptops, tablets, iPad, Android, & other smartphones.
- "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]
- * Safety Hazards and Safe Inspection Procedures 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.
- "Simplified Electrical Wiring," Sears, Roebuck and Co., 15705 (F5428) Rev. 4-77 1977 [Lots of sketches of older-type service panels.]
- "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.
- Eric Galow, Galow Homes, Lagrangeville, NY. Mr. Galow can be reached by email: ericgalow@gmail.com or by telephone: 914-474-6613. Mr. Galow specializes in residential construction including both new homes and repairs, renovations, and additions.
- 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. Contact Mark Cramer at: 727-595-4211 mark@BestTampaInspector.com 11/06
- Roger Hankey is principal of Hankey and Brown home inspectors, Eden Prairie, MN. Mr. Hankey is a past chairman of the ASHI Standards Committee. Mr. Hankey has served in other ASHI professional and leadership roles. Contact Roger Hankey at: 952 829-0044 - rhankey@hankeyandbrown.com. Mr. Hankey is a frequent contributor to InspectAPedia.com.
- Arlene Puentes, an ASHI member and a licensed home inspector in Kingston, NY, and has served on ASHI national committees as well as HVASHI Chapter President. Ms. Puentes can be contacted at ap@octoberhome.com
- Wikipedia provided background information about some topics discussed at this website provided this citation is also found in the same article along with a " retrieved on" date. NOTE: because Wikipedia entries are fluid and can be amended in real time, we cite the retrieval date of Wikipedia citations and we do not assert that the information found there is necessarily authoritative.
Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair
 The Home Reference Book - the Encyclopedia of Homes, Carson Dunlop & Associates, Toronto, Ontario, 25th Ed., 2012, is a bound volume of more than 450 illustrated pages that assist home inspectors and home owners in the inspection and detection of problems on buildings. The text is intended as a reference guide to help building owners operate and maintain their home effectively. Field inspection worksheets are included at the back of the volume. Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
Or choose the The Home Reference eBook for PCs, Macs, Kindle, iPad, iPhone, or Android Smart Phones. Special Offer: For a 5% discount on any number of copies of the Home Reference eBook purchased as a single order. Enter INSPECTAEHRB in the order payment page "Promo/Redemption" space.
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