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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 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. 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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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
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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
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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.
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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)
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To expand on Roger's expansion. 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
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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.
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Here is the substantiation that got it into the 2002 code. 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
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resqcapt19 ---
The missing ground pin is a UL problem not a NEC problem.
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George, The missing ground pin is a UL problem not a NEC problem. It is a real world safety problem. 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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