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Joined: Jan 2003
Posts: 4,391
I
Moderator
Follow the link below and it will take you to an appliance leakage tester.

This the type of tool to use to determine if the appliance is faulty.

http://www.simpsonelectric.com/229-2.htm

From the site

Quote
Why Measure Leakage Current?
The primary purpose of measuring leakage current of electrically operated
equipment is to determine whether usage in a normal manner can present
an electrical safety hazard to the user. Leakage current may increase with
use and aging of the appliance and should be checked periodically to assure
continued safety to the user. Equipment with protective grounding through
the power cord is assumed to have faulty grounding connection at the outlet
when measuring leakage current. While the shock (see definition of shock
hazard on page 3 ) in itself might be slight from the standpoint of bodily harm,
the person, nevertheless might react violently out of surprise or fear, and may
cause injury to himself or someone else.

Quote
SHOCK HAZARD: As defined in American National Standard, C39.5, Safety
Requirements for Electrical & Electronic Measuring & Controlling Instrumentation,
a shock hazard shall be considered to exist at any part involving a
potential in excess of 30 volts RMS (sine wave) or 42.4 volts DC or peak and
where a leakage current from that part to ground exceeds 0.5 milliampere,
when measured with an appropriate measuring instrument defined in Section
11.6.1 of ANSI C39.5.

If an appliance is constantly triping a GFCI it surly will not pass the leakage test.

Bob

[This message has been edited by iwire (edited 02-17-2005).]


Bob Badger
Construction & Maintenance Electrician
Massachusetts
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Joined: May 2004
Posts: 162
C
Member
GamecockEE


The NEC is a consensus code giving anyone and everyone from anywhere and everywhere an opportunity to contribute of criticize through a proposal stage , a comment stage and annual meeting. Interested parties, yea or nay may gather and give input to each and every article in the Code. But there is a process.

The CMP in general can only act upon proposals and comments made by the public.So if one is not made they are basically unable to take action. Like all Democratic processes there are rules and regulations. If you are compelled to do so get involved. Proposal sheets are in the back of every NFPA Doc. or visit!!
http://www.nfpa.org/index.asp

Joined: May 2002
Posts: 1,716
R
Member
To expand on the monitoring of the refrigerator.

It is not to difficult to tie an alarm to a dialer to notify say the manager and assistant manager(s) in the event of the refrigerator loosing power, especially if the restaurant already has a security alarm system.

We do this with MRI cooling units in small facilities.

Roger

Joined: Feb 2002
Posts: 375
G
Member
We have the option of

1) hardwired and no GFCI

or

2) cord & plug and GFCI

Unless there is some functional difference between hardwired and cord & plug there is no rational reason for allowing 1) and not allowing

3) cord & plug and no GFCI.

It is irrational sections of the code like this that bring about disrespect for the code.

Joined: Nov 2000
Posts: 2,148
R
Member
George,
It is much more likely that the EGC will become disconnected when the equipment is cord and plug connected, than when it is hard wired. How many times have you seen a male cord end with the ground pin missing? Look at almost all of the GFCI rules...they apply mostly to cord and plug connected equipment, not hard wired equipment.
Don

[This message has been edited by resqcapt19 (edited 02-17-2005).]


Don(resqcapt19)
Joined: Jan 2003
Posts: 4,391
I
Moderator
To expand on Roger's expansion. [Linked Image]

We wire a lot of supermarkets and 99% of the refrigerated cases are remote monitored and will trigger an alarm signal if the temp is high.

They also call out to a central monitoring station.

It could also be as easy as a small battery powered unit that has sticky back tape that mounts on the outside of the refrigerator with a probe placed inside the refrigerator.


Bob Badger
Construction & Maintenance Electrician
Massachusetts
Joined: Jul 2004
Posts: 49
G
Member
Looks like I stirred up some good discussion. When I worked in the industrial sector, we used leakage current testers as part of our electrical integrity program on drop cords and hand tools. Thanks for the other information that came out of this thread.

Joined: Aug 2003
Posts: 1,374
R
Moderator
Here is the substantiation that got it into the 2002 code.
Quote
SUBMITTER: Michael J. Johnston, International Association of
Electrical Inspectors
COMMENT ON PROPOSAL NO: 2-35
RECOMMENDATION: Requesting that the Code Making Panel
reconsider the action on this proposal. This proposal should be
accepted and additional information has been provided to be
included as substantiation. Normally the code gets changed or
revised based on history or data. It also can be changed or revised
based on additional safety that the changes affords the users and
general public. The code is not very often changed in a proactive
manner. Accepting this proposal does address all of these areas.
It provides added safety from electrical shock and electrocution, it
is in parallel with the requirements already in place for dwelling
units. The hazards are the same, and sometimes even greater in
occupancies other than dwelling units. Accepting this proposal
would be proactive and would increase the safety for users and the
public.
SUBSTANTIATION:
Subject: 25-year-old Restaurant Manager Electrocuted in North
Carolina
Cause: Electrocution
Summary: On August 3, 1986, a 25-year-old male restaurant
manager was cleaning the floor of the kitchen when he came in
contact with a refrigerator that had a ground fault. The manager
was electrocuted. The restaurant was closed and the manager’s
wife and 2-year-old daughter were in the dining area waiting for
him to finish. The victim, who was wearing tennis shoes, put soap
and water on the floor. He slipped and grabbed the handle of a
commercial refrigerator. The refrigerator had a ground fault – the
cord did not have a ground prong. The ground fault was
apparently caused by excessive wear on the insulation of the
conductors (wires) supplying power to the compressor. The
conductors were exposed at a cut-out hole in the case of the
refrigerator, were not protected from abrasion, and were not
protected by strain relief. The victim’s wife heard a noise in the
kitchen. She successfully pulled the victim from the refrigerator
into the dining area, though she was shocked in the process. She
summoned help and began CPR, but to no avail.
Recommendations:
• All electrical equipment (such a refrigerator) should be
designed and maintained to comply with all applicable
requirements of the National Electrical Code. In this case, the
defects in the refrigerator apparently developed over time and were
not recognized as hazardous. The refrigerator was bought used
and the owner had no owner’s manual.
• Restaurant owners and managers should be encouraged to
conduct formalized safety training for all restaurant employees.
• All electrical receptacles (outlets) in restaurant kitchens should
be protected by ground fault circuit interrupters. See NIOSH Alert
(85-104).
Subject: Electrocution in a Fast Food Restaurant
Cause: Electrocution
Summary: On June 30, 1984, at about 1:05 A.M., an 18-year-old
male employee with 15 months experience at a fast food restaurant
was electrocuted while plugging a portable electric toaster into a
110 volt/20 amp receptacle.
At the time of the incident, employees had closed the restaurant
and damp-mopped the floors. About 5 to 10 minutes after
mopping, the victim was in the process of plugging the toaster into
a floor outlet when he received a shock. The assistant manager
and other employees were elsewhere and did not see the victim.
The assistant manager heard a scream and investigated. The
assistant manager and the other workers found the victim with one
hand on the plug, and the other hand wrapped around the
receptacle box, and with his face on top of the outlet. An
employee tried to take the victim’s pulse but was shocked. The
assistant manager went to the breaker box to open the breaker for
that circuit, but could not find the specific breaker. He then called
the emergency squad, returned to the box and found the right
breaker. The victim had by then been in contact with the current
for 3 to 8 minutes. An employee checked the victim’s pulse and
found very rapid radial pulse. The employee and assistant manager
then unlocked the front door and placed another call to the rescue
squad. The employee check the victim’s pulse again and found
none. An employee living nearby arrived and started CPR, which
was continued by the rescue squad upon its arrival. CPR was
administered for 1./5 hours. The victim was DOA at the local
hospital. Two different electricians later evaluated the circuit and
found no serious problems. It is surmised that while holding the
plug, the victim’s right hand slipped forward to make contact
through the index finger to the energized prong. With his left hand
holding the spring-loaded cover open, a current path through the
arms, chest, and heart would be established from the prong to the
ground. After the accident the employer required employees to
open circuits at the breaker box before plugging and unplugging
equipment. This strategy is not recommended because it relies on
positive human action and places excessive wear on breakers.
Recommendations:
• Ground Fault Circuit Interrupter Breakers (GFCI’s) would have
interrupted the circuit before sufficient current has passed to cause
physical damage to the body. They are recommended as the best
solution.
• The location and design of the receptacles, the design of the
plug, and the recent mopping contributed to the incident.
• CPR should be initiated when an unstable pulse is detected,
rather than later when no pulse is found.
Subject: Worker Electrocuted in Mushroom Cannery in Ohio
Cause: Electrocution
Summary: On March 5, 1985, a 21-year-old male was electrocuted
while attempting to unclog a drain trough located beneath a
mushroom processing table. Apparently, the worker steadied
himself by grasping the motor connection box while kneeling in
water.
Prior to the accident, the cannery owner had been ordered by the
city to reduce the amount of solid waste leaving the plant, because
it was plugging drains and causing floods on public property. The
employer tried to use removable filters over the drains, but
employees failed to replace the filters, and so the employer bolted
down a solid grate that had to cleaned by hand. At 9:30 A.M., the
victim was ordered to the mushroom processing room and told to
unclog a 7-inch-wide drain trough located under a processing
table. A motor connection box was located under the table, 42
inches above the trough. Water had backed up behind the drain to
form a pool 3 feet in diameter and 4 inches deep. The worker was
in contact with the electric current for about 15 seconds. The
worker was not observed, but a co-worker who reached for the
victim received a shock, and a second worker was shocked by the
table. Another co-worker immediately de-enrgized the equipment
and the victim fell face down in the water. Medics arrived 8
minutes after the incident and attempted to revive the victim, who
was DOA at a local hospital. On opening the motor connection
box about 8 ounces of water poured out. The box was rusted and
had many sharp edges.
(text illegible)
of the insulation was torn off and was probably the source of the
electrical energy. The insulation could have been torn by pulling
on the box’s power cord. The motor was not suitable for wet
applications.
NFPA 70 — May 2001 ROC — Copyright 2001, NFPA
57
Recommendations:
• The plant’s electrical system should be inspected and brought
up to the requirements of the National Electrical Code. Where
appropriate, ground-fault circuit breakers should be installed.
• Workers should be required to wear appropriate protective gear.
• Insulating barriers mechanically attached to the processing
machinery would be desirable.
• The mushroom processing procedure should be modified to
reduce the number of mushrooms that fall on the floor.
• Management should implement a hazard identification program
and request help from the Industrial Commission of Ohio in
developing a comprehensive health and safety program.
Subject: Maintenance Mechanic Electrocuted While Touching
Damaged Power Cord
Cause: Electrocution
Summary: On December 22, 1988, a 37-year-old male
maintenance mechanic was electrocuted when he grasped a power
cord with damaged insulation and contacted an exposed energized
conductor. The employer is a meat-packing plant. At the end of
each production shift, maintenance workers unplug two strapping
machines used to package meat, and move them to the
maintenance shop for the night. The plant floor is then washed.
The machines are inspected and returned the next day. The
machines are portable wheel-mounted units. Strapping material is
fed from a fiberglass spool mounted on top. The machines have
flexible power cords with twist-lock male plugs, attached to
receptacles (outlets) on the end of cords hanging from the ceiling.
On the day of the incident, a power cord on one machine was
repeatedly rubbed by the edge of the rotating fiberglass spool. The
point of contact was about 2.5 inches from the plug. Friction wore
a half inch-long hole through the outer cover and through the
insulation around one wire. The floor was wet. Fiberglass in nonconductive,
and so the damage did not energize the machine. At
about 5:00 P.M. the victim came to unplug the machine. He was
wearing a damp pair of worn leather boots. As he grasped the
plug, a finger of his right hand contacted the damaged section of
cable and a bare 277-volt conductor. Current passed through his
body to the wet floor. A foreman tried to free the victim’s hand
with a plastic scoop, but failed. The forman then struck the plug
above the victims’ hand knocking it loose from the cable. The
victim lost consciousness. A company nurse began CPR, and a
rescue squad was notified. The victim was pronounced dead about
1 hour and 15 minutes after the incident.
Recommendations:
• Permanent fixed wiring should be used whenever possible.
When this is not practical, armored or protected cable should be
used when cables can be contacted by moving parts.
• Strain relief should be provided where connections on power
cords are subject to being pulled apart. See the National Electrical
Code (NEC 400-10).
• Disconnect devices should be located close to equipment. See
NEC 380-8. If the possibility of confusion exists, the disconnects
should be clearly labeled. See NEC 110-22.
• Electrical safety training should be provided to all employees
likely to be exposed to energized equipment.
• Periodic safety inspection of all electrically powered equipment
should be performed to detect and correct problems. In this case,
though the machines were “inspected”, no one noticed that the
damaged power cord had been previously abraded.
Prevention: Elements of an Electrical Safety Program (text
illegible)
At least on of the following five factors was present in all 224
incidents evaluated by the FACE program: (1) established safe
work procedures were either not implemented or not followed; (2)
adequate or required personal protective equipment was not
provided or worn; (3) lockout-tagout procedures were either not
implemented or not followed; (4) compliance with existing OSHA,
NEC, and NESC regulations were not implemented; and (5)
worker and supervisor training in electrical safety was not adequate.
These subjects are addressed in various NIOSH Alters 26-36 and
related publications. 37
Most of the 224 occupational electrocution incidents investigated
as part of the FACE program could have been prevented through
compliance with existing OSHA, NEC, and NESC regulations;
and/or the use of adequate personal protective equipment (PPE).
All workers should receive hazard awareness training so that they
will be able to identify existing and potential hazards present in
their workplaces and relate the potential seriousness of the injuries
associated with each hazard. Once these hazards are identified,
employers should develop measures that would allow for their
immediate control. Based on an analysis of this data, to reduce
occupation electrocutions, employers should:
• Develop and implement a comprehensive safety program and,
when necessary, revise existing programs to throughly address the
area of electrical safety in the workplace.
Ensure compliance with existing OSHA regulations Subpart S of 29
CFR 1910.302 through 1910.399 of the General Industry Safety and
Health Standards3 and Subpart K of 29 CFR 1926.402 through
1926.408 of the OSHA Construction Safety and Health Standards4 .
• Provide all workers with adequate training in the identification
and control of the hazards associated with electrical energy in their
workplace.
• Provide additional specialized electrical safety training to hose
workers working with or around exposed components of electric
circuits. This training should include, but not be limited to,
training in basic electrical theory, proper safe work procedures,
hazard awareness and identification, proper use of PPE, proper
lockout/tagout procedures, first aid including CPR, and proper
rescue procedures. Provisions should be made for periodic
retraining as necessary.
• Develop and implement procedures to control hazardous
electrical energy which include lockout and tagout procedures and
ensure that workers follow these procedures.
• Provide those workers who work directly with electrical energy
with testing or detection equipment that will ensure their safety
during performance of their assigned tasks.
• Ensure Compliance with the National Electrical Code5 and the
National Electrical Safety Code6 .
• Conduct safety meetings at regular intervals.
• Conduct scheduled and unscheduled safety inspections at
worksites.
• Actively encourage all workers to participate in workplace safety.
• In construction setting, conduct a jobsite survey before starting
any work to identify any electrical hazards, implement appropriate
control measures, and provide training to employees specific to all
identified hazards.
• Ensure that proper personal protective equipment is available
and worn by workers where required (including fall protection
equipment).
• Conduct job hazard analyses of all tasks that might expose
workers to the hazards associated with electrical energy and
implement control measures that will adequately insulate and
isolate workers from electrical energy.
• Identify potential electrical hazards and appropriate safety
interventions during the planning phase of construction or
maintenance projects. This planning should address the project
from start to finish to ensure workers have the safest possible work
environment.
The FACE data indicates that although many companies had
comprehensive safety programs, in many cases they were not
completely implemented. This underscores the need for increased
management and worker understanding, awareness, and ability to
identify the hazards associated with working on or in proximity to
develop and implement a comprehensive safety program. In some
cases, this may entail the development of additional worker
training, and/or the evaluation and restructuring of existing safety
programs. Management should also provide adequate training in
electrical safety to all workers and strictly enforce adherence to
established safe work procedures and policies. Additionally,
adequate personal protective equipment should be available where
appropriate. Information or assistance in accomplishing these
measures can be provided by OSHA, electrical safety consultants,
or other agencies or associations that deal with electrical safety. A
strong commitment to safety by both management and workers is
essential in the prevention of severe occupational injuries and
death due to contact with electrical energy.
Overview of Electrical Hazards, Virgil Casini, B.S.
Electricity is a ubiquitous energy agent to which many workers in
different occupations and industries are exposed daily in the
performance of their duties. Many workers know that the principal
danger from electricity is that of electrocution, but few really
understand just how minute a quantity of electrical energy is
required for electrocution. In reality, the current drawn by a tiny
7.5 watt, 120-volt lamp, passed from hand to hand or hand to foot
across the chest is sufficient to cause electrocution. 1 The number
of people who believe that normal household current is not lethal
or that powerlines are insulated and do not pose a hazard is
alarming. Electrocutions may result from contact with an object as
seemingly innocuous as a broken light bulb or as lethal as an
overhead powerline, and have affected workers since the first
electrical fatality was recorded in France in 1879 when a stage
carpenter was killed by an alternating current of 250 volts.2
The information in the following two sections (Definitions and
Effects of Electrical Energy) is intended as a basic explanation of
electricity and the effects of electrical energy. Unless otherwise
indicated, information in these sections is derived from OSHA
NFPA 70 — May 2001 ROC — Copyright 2001, NFPA
58
electrical standards, 3,4 the National Electrical Code (NEC)5 , and
the National Electrical Safety Code 6. Official definitions of
electrical terms can be found in these same documents.
Definitions:
Electricity is the flow of an atom’s electrons through a conductor.
Electrons, the outer particles of an atom contain a negative charge.
If electrons collect on an object, that object is negatively charged.
If the electrons flow from an object through a conductor, the flow
is called electric current. Four primary terms are used in
discussing electricity: voltage, resistance, current and ground.
Voltage is the fundamental force or pressure that causes electricity
to flow through a conductor and is measured in volts. Resistance
is anything that impedes the flow of electricity through a conductor
and is measured in Ohms. Current is the flow of electrons from a
source of voltage through a conductor and is measured in amperes
(Amps). If the current flows back and forth (a cycle) through a
conductor, it is called alternating current (AC). In each cycle the
electrons flow first in one direction, then the other. In the United
States, the normal rate is 60 cycles per second {or 60 Hertz (Hz)].
If current flows in one direction only (as in a car battery), it is
called direct current (DC).
AC is most widely used because it is possible to step up or step
down (i.e., increase or decrease) the current through a
transformer. For example, when current from an overhead
powerline is run through a pole-mounted transformer, it can be
stepped down to normal household current.
OHM’s (current = voltage/resistance) can be used to rotate these
three elements mathematically. A ground is a conducting
connection, whether or not unitentional, between an electric
circuit on equpment and the earth or some conducting body that
serves in place of the earth.
Effects of Electrical Energy
Electrical injuries consist of four main types: electrocution
(fatal), electric shock, burns, and falls caused as a result of contact
with electrical energy.
Electrocution results when a human is exposed to a lethal amount
of electrical energy. To determine how contact with an electrical
source occurs, characteristics of the electrical source before the
time of the incident must be evaluated (pre-event). For death to
occur, the human body must become part of an active electrical
circuit having a current capable of overstimulating the nervous
system or causing damage to internal organs. The extent of
injuries received depends on the current’s magnitude (measured in
Amps), the pathway of the current through the body and the
duration of current flow through the body (event) the resulting
damage to the human body and the emergency medical treatment
ultimately determine the outcome of the energy exchange (postever)
7 .
Electrical injuries may occur in various ways: direct contact with
electrical energy, injuries that occur when electricity arcs (an arc is
a flow of electrons through a gas, such as air) to a victim at ground
potential (supplying an alternative path to ground), flash burns
from the heat generated by an electrical arc, and flame burns from
the ignition of clothing or other combustible, nonelectrical
materials. Direct contact and arcing injuries produce similar
effects. Burns at the point of contact with electrical energy can be
caused by arcing to the skin, heating at the point of contact by a
high-resistance contact or higher voltage currents. (text illegible)
voltages will normally result in burns at the sites where the
electrical current enters and exits the human body. High voltage
contact burns may display only small superficial injury; however,
the danger of these deep burns destroying tissue subcutaneously
exists. 8 Additionally, internal blood vessels may clot, nerves in the
area of the contact point may be damaged, and muscle
contractions may cause skeletal fractures either directly or in
association with falls from elevation.9 It is also possible to have a
low-voltage electrocution without visible marks to the body of the
victim.
Flash burns and flame burns are actually thermal burns. In these
situations, electrical current does not flow through the victim and
injuries are often confined to the skin.
Contact with electrical current could cause a muscular
contraction or a startle reaction that could be hazardous if it leads
to a fall from elevation (ladder, aerial bucket, etc.) or contact with
dangerous equipment.10
The NEC describes high voltage as greater than 600 volts AC.5
Most utilization circuits and equipment operate at voltages lower
than 600 volts, including common household circuits 110/120
volts); most overhead lighting systems used in industry or office
buildings and department stores; and much of the electrical
machinery used in industry, such as conveyor systems, and
manufacturing machinery such as weaving machines, paper rolling
machines or industrial pumps.
Voltages over 600 volts can rupture human skin, greatly reducing
the resistance of the human body, allowing more current to flow
and causing greater damage to internal organs. The most common
high voltages are transmission voltages (typically over 13,900 volts)
and distribution voltages (typically under 13,900 volts). The latter
are the voltages transferred from the power generation plants to
homes, offices and manufacturing plants.
Standard utilization voltages produce currents passing through a
human body in the milliampere (mA) range (1,000 mA= 1Amp).
Estimated effects of 60 Hz AC currents which pass through the
chest are shown in Table 1.
Table 1. Estimated Effects of 60 Hz AC Currents
1 mA Barely perceptible
16 mA maximum current an average man can grasp
and “let go”
20 mA Paralysis of respiratory muscles
100 mA Ventricular fibrillation threshold
2 Amps Cardiac standstill and internal organ damage
15/20 Amps Common fuse or breaker opens circuit*
* Contact with 20 miliamps of current can be fatal. As a frame of
reference, a common household circuit breaker may be rated at 15,
20 or 30 amps.
When current greater than 16 mA “let go current” passes through
the forearm, it stimulated involuntary contraction of both flexor
and extensor muscles. When the stronger flexors dominate, victims
may be unable to release the energized object they have grasped as
long as the current flows. If current exceeding 20 mA continues to
pass through the chest for an extended time, death could occur
from respiratory paralysis. Currents of 10 MA or more, up to 2
Amps, may cause ventricular fibrillation, probably the most
common cause of death from electrical shock.11 Ventricular
fibrillation is the uneven pumping of the heart due to the
uncoordinated, asynchronous contraction of the ventricular muscle
fibers of the heart that leads quickly to death from lack of oxygen to
the brain. Ventricular fibrillation is terminated by the use of a
defibrillation, which provides a pulse shock to the chest to restore
the heart rhythm. Cardiopulmonary resuscitation (CPR) is used as
a temporary care measure to provide the circulation of some
oxygenated blood to the brain until a defibrillator can be used.23
The spread with which resuscitative measures are initiated has
been found to be critical. Immediate defibrillation would be ideal;
however, for victims of cardiopulmonary arrest, resusciation has
the greatest rate of success if CPR is initiated within 4 minutes and
advanced cardiac life support is initiated within 8 minutes
(National Conference on CPR and ECC, 1986).6
The presence of moisture from environmental conditions such as
standing water, wet clothing, high humidity, or perspiration
increases the possibility of a low-voltage electrocution. The level
of current passing through the human body is directly related to
the resistance of its path through the body. Under dry conditions,
the resistance offered by the human body may be as high as 100,000
Ohms. Wet or broken skin may drop the body’s resistance to 1,000
Ohms. The following illustrations of Ohm’s law demonstrates how
moisture affects low-voltage electrocutions. Under dry conditions,
Current=Volts/Ohms = 120/100,000 = 1 mA, a barely perceptible
level of current. Under wet conditions, Current=Volts/Ohms =
120/1,000 = 120 mA, sufficient current to cause ventricular
fibrillation. Wet conditions are common during low-voltage (text
illegible)
High voltage electrical energy quickly breaks down human skin,
reducing the human body’s resistance to 500 Ohms. Once the skin
is punctured, the lowered resistance results in massive current flow,
measured in Amps. Again, Ohm’s law is used to demonstrate the
action. For example, at 1,000 volts, Current = Volts/Ohms =
1000/500 = 2 Amps, which can cause cardiac standstill and serious
damage to internal organs.
Conclusions:
Electrical hazards represent a serous, widespread occupational
danger; practically all members of the workforce are exposed to
electrical energy during the performance of their daily duties, and
electrocutions occur to workers in various job categories. Many
workers are unaware of the potential electrical hazards present in
their work environment, which makes them more vulnerable to the
danger of electrocution.
The Occupational Safety and Health Administration (OSHA)
addresses electrical safety in Subpart S 29 CFR 1910.302 through
1910.399 of the General Industry Safety and Health Standards. 3 The
standards contain requirements that apply to all electrical
installations and utilization equipment, regardless of when they
were designed or installed. Subpart K of 29 CFR 1926.402 through
1926.408 of the OSHA Construction Safety and Health Standards4
contains installation safety requirements for electrical equipment
NFPA 70 — May 2001 ROC — Copyright 2001, NFPA
59
and installations used to provide electric power and light at the
jobsite. These sections apply to both temporary and permanent
installations on the jobsite.
Additionally, the National Electrical Code (NEC)5 and the
National Electrical Safety Code (NESC) 6 comprehensively address
electrical safety regulations. The purpose of the NEC is the
practical safeguarding of persons and property from hazards arising
from the use of electricity. The NEC contains provisions
considered necessary for safety and applies to the installation of
electric conductors and equipment within or on public or private
buildings or other structures, including mobile homes,
recreational vehicles, and floating buildings; and other premises
such as yards; carnival, parking, and other lots; and industrial
substations.
The NEC serves as the basis for electrical building codes across
the United States.
The NESC contains rules necessary for the practical safeguarding
of person during the installation, operation, or maintenance of
electric supply and communication lines and associated
equipment. These rules contain the basic provisions that are
considered necessary for the safety of employees and the public
under the specified conditions. Unlike the NEC, the NESC
contains work rules in addition to installation requirements.
Preventing Electrocution of Workers in Fast Food Restaurants
NIOSH Alert: December 1984
DHHS (NIOSH) Publication No. 85-104
Background:
On June 30, 1984, an 18-year-old male worker in a fast food
restaurant dies by electrocution on the job. The worker, who had
15 months’ work experience at this restaurant, was electrocuted
while kneeling to insert the plug of a portable electric toaster into a
110/120V/20 amp outlet on a floor which had recently been (text
missing)
receptacle box. Another worker who attempted to “take the pulse”
of the victim received an electrical shock but was not injured.
When the assistant manager saw what was happening, he went to
the breaker box to shut off the current but was unable to locate the
appropriate breaker. The emergency rescue squad was called, and
before they arrived, the proper circuit breaker was located and
thrown. By that time, the victim had been in contact with the
electricity for three to eight minutes. Attempts at cardiopulmonary
resuscitation (CPR) by fellow workers and members of the
emergency rescue squad were unsuccessful; the victim was
pronounced dead on arrival at a nearby hospital.
The specific events that resulted in this electrocution could not
be defined with absolute precision. However, investigators from
NIOSH concluded that while the victim was inserting the plug of
the toaster into the receptacle with his right hand and holding
open the grounded metal receptacle cover with his left hand, the
index finger of his right hand touched an energized prong of the
plug and he received an electrical shock across the chest.
Recommendations by NIOSH
Because one-tenth (0.1) amp of electricity flowing through the
human body for two seconds can cause death any active electrical
circuit can pose a potentially lethal hazard.
Electrical hazards in the kitchens of commercial restaurants are
particular concern because of the variety of electrical appliances in
use. However, safeguards and safe work practices can eliminate
most of these hazards NIOSH recommends that:
1. Ground fault circuit interrupters (GFCIs) of the breaker or
receptacle type be installed in situations where electricity and
wetness coexist. GFCIs will interrupt the electrical circuit before
current sufficient to cause death or serous injury has passed
through the body. GFCIs are inexpensive ($50.00-$85.00 for
breaker type, $25.00-$45.00 for receptacle type) and a qualified
electrician can install them in existing electrical circuits with
relative ease;
2. Exposed receptacle boxes be made of nonconductive material
so that contact with the box will not constitute “a ground”;
3. Plugs and receptacles be designed to prevent energization until
insertion is complete;
4. All circuit breaker or fuse boxes bear a label for each circuit
breaker or fuse which clearly identifies its corresponding outlets
and fixtures. Also, breaker switches should not be used for on-off
switches;
5. All workers, when hired, be made aware of electrical hazards
and of safe work practices by which to avoid these hazards.
Workers should be informed that, in the event of an electrical
injury, no contact should be made with the victim or the electrical
apparatus causing the injury until the current has been shut off;
and that
6. Workers in the restaurant be encouraged to train in CPR.
We are requesting that editors of appropriate trade journals,
health officials, and especially food service inspectors institute and
bring these recommendations to the attention of restaurant
managers and owners and potential victims. Suggestions, requests
for additional information on control practices, or questions
related to this announcement should be directed to Mr. John
Moran, Director, Division of Safety Research, National Institute for
Occupational Safety and Health, 944 Chestnut Ridge Road,
Morgantown, West Virginia 26505, Telephone (304) 291-4595.
We greatly appreciate your assistance. J. Donald Millar, M.D.,
D.T.P.H. (Lond.), Assistant Surgeon General, Director, National
Institute for Occupational Safety and Health, Center for Disease
Control
PANEL ACTION: Accept in Principle in Part.
PANEL STATEMENT: See panel action and statement on
Comment 2-13.
NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 12
VOTE ON PANEL ACTION:
AFFIRMATIVE: 12
___________


Ryan Jackson,
Salt Lake City
Joined: Feb 2002
Posts: 375
G
Member
resqcapt19 ---

The missing ground pin is a UL problem not a NEC problem.

Joined: Nov 2000
Posts: 2,148
R
Member
George,
Quote
The missing ground pin is a UL problem not a NEC problem.
It is a real world safety problem.
Quote
The purpose of this Code is the practical safeguarding of persons and property from hazards arising from the use of electricity.
The use of a GFCI fits the purpose of the code.
Don


Don(resqcapt19)
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