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IAEI News provides educational forums, updates on electrical codes and reports of innovative research to facilitate the development and enforcement of practices designed to drive efficiency and compliance with the highest standards of product development and safety—for the public as well as for electrical personnel. The magazine reaches authorities with power of product specification, approval and acceptance. Published six times a year by the International Association of Electrical Inspectors.

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Electric Sign Inspections: Listed Signs and Listed Section Signs

Posted By Michael Johnston, Thursday, May 01, 2003
Updated: Thursday, February 14, 2013

TheNational Electrical Code(NEC) is a minimum electrical safety standard; its primary purpose is directed at protection of persons and property from electrical hazards. Hazards of electrical shock, electrocution, and fires are some of the more serious consequences of noncompliance with minimum rules for safety. The NEC is the most widely adopted code in the world and many jurisdictions adopt it in its entirety without exception or local amendments or supplements. This article focuses on electrical signs and neon installations, what is included under the scope of Article 600, and some of the basics relative to the electrical inspection process.

Interpretations and Enforcement of the Code


Photo 1. Typical field-installed skeletal tubing neon sign installed in an indoor (dry) location required to be in compliance with applicable rules of Part 1 and specifically Part 2 of Article 600

Section 90.4 indicates that the authority having jurisdiction has the responsibility for interpretation and enforcement of the rules. When a jurisdiction adopts theCodeinto law, the jurisdiction has a responsibility to attain minimum compliance with those rules that are the law. The responsibility of electrical sign inspection is handled in different ways from region to region in this country, but the importance is the same everywhere. Some jurisdictions handle the inspections of signs as a function of the electrical inspector, while others assign designated sign inspectors that handle these responsibilities. Some jurisdictions adopt the Code, including Article 600, but do not inspect electric signs or neon installations at all. In which of these categories is your jurisdiction? Inspection of electric signs and outline lighting systems is an important aspect in helping ensure electrical safety for persons and property as outlined in the first section of the Code as its purpose. Photo 1

Approvals


Figure 1. Typical listing mark for an electric sign (self contained)

The authority having jurisdiction is responsible for approvals of electrical installations; and if theNECis adopted in its entirety without excluding Article 600, electrical signs and outline lighting, including neon lighting installations and systems, are included in that responsibility. Section 110.2 indicates that electrical conductors and equipment under the scope of theNECare only acceptable if approved. One can conclude that approval for electrical signs and outline lighting installations can be achieved by standing inspection. If an electrical sign never stands inspection, it obviously has no approval.

Typical field-installed skeletal tubing neon sign installed in an indoor (dry) location required to be inspected for compliance with applicable rules of Part I and specifically Part II of Article 600.

In the Real World


Photo 2. Typical electric sign listing mark and other required marks (CSA)

Many electric signs and neon installations are not being inspected even though it is a requirement when a jurisdiction adopts the electrical code into law. This is a far too common dilemma in this country these days and is worthy of strong consideration by those responsible. Data and records on file at NFPA headquarters in Quincy, Massachusetts, indicate an abundance of electrical fires directly related to electrical signs and, more specifically, high voltage neon installations. There is a growing genuine need for more consistent and uniform enforcement of electrical code requirements for these types of installations. Effective enforcement of the Code requirements related to electric signs and neon installations involves becoming familiar with these systems. It involves an effort to become educated and knowledgeable and also requires good communication with the sign industry. It is important not to take the uninformed approach here. It is every bit as important to make a thorough electrical inspection of a neon sign as it is to make one of a 5,000-volt unit substation secondary. The electrical hazards are similar. Photo 2

Listed Electric Signs


Figure 2. Typical electric sign listing markings found on each section including the transformer section of the sign

The NEC actually helps the process along by a requirement that all electric signs and outline lighting, including fixed, portable, or mobile, be listed and installed in conformance with that listing. These types of equipment and installations can also be approved by special permission, which, by definition, means approved in writing by the authority having jurisdiction. Some unique installations may not be listed, and approvals are often granted by special permission. The key is that there is an approval granted for the installation by the responsible entity. Most inspectors base their approvals on the use of listed equipment. With the requirements for listing in 600.3, the job of inspector is made a bit easier because a qualified electrical testing laboratory is involved in the conformance assessment process.


Photo 3. Listed electric sign in the form of letters on a raceway with transformers and high voltage secondary in the metallic enclosure self-contained.

Section 90.7 provides information that indicates listing and examinations for safety made under standard conditions can serve as a basis for approvals of specific equipment and items referred to by the Code. It is not intended that factory-installed internal wiring or construction of listed equipment (electric signs) be inspected at the time of installation other than to possibly detect damage or modifications. However, this listed equipment must meet the minimum requirements of any applicable safety electrical standard. Electric signs fall under the scope of UL Standard 48 and are required by third party testing organizations to comply with the requirements in the standard. These types of equipment (electric signs and outline lighting) are suitable for installation in accordance with the installation rules of the NEC. This basically means that the internal wiring and components of listed electric signs evaluated to comply with UL 48 prior to installation in the field so they are not required to be inspected for compliance with Standard 48 at the time of installation. However, any field wiring or connection to such listed units is required to be inspected for compliance with the NEC. The listing covers the equipment only and not the field wiring.


Figure 3. Listed section signs made up of five sections, one section is the transformer or power supply

Field wiring must be inspected to verify such things as grounding and bonding connections, proper wiring methods, suitable and properly sized conductors, supports, and suitability of the location it is installed in, to name a few. A listed electrical sign includes a sign body, a fluorescent ballast, transformer or power supply, secondary wiring, and lamps or tubing. Generally this is a fairly elementary electrical inspection. It is, by comparison, similar to an inspection of an electrical luminaire (lighting fixture) installed in a building. Listed electrical signs include listed assemblies that are incandescent, fluorescent, cold cathode, or neon. They generally are self-contained and require a field connection of a required minimum rated branch circuit. As specified in Section 90.4 of the NEC, it is not the responsibility of electrical inspectors to verify that the internal workings of a listed sign have met the minimum provisions in applicable safety standards.


Photo 4. Listed section signs include two additional sections behind the wall that contain the neon transformers for the sign

Sometimes listed electric signs are so large they have to be delivered to the installation site in two or more segments and assembled upon installation. The segments are put together to form an overall single listed sign. This is not a listed section sign, as it will include one "listed electric sign” label. The only field connections required for this sign are the connection of the sign circuit conductors and any grounding and bonding connections. These connections would be required to be verified by the electrical inspector.

Listed Electrical Section Signs


Figure 4. Typical listing markings for a section sign

Another listed electrical sign falling under the scope of UL Standard 48 is a sign that is listed in sections. This listing covers each section of the overall sign as a complete entity made of several sections. Each one of the sections, including the transformer or power supply, must meet the requirements of UL 48. Each listed section is also required to be labeled or marked as a listed sign section (see figure 2). This includes any section(s) of the sign that include the transformer or power supply (see photo 4).

For example, if a listed section sign included the letters "N,” "E,” "O,” and "N” to form the electric sign copy "”NEON,”" and it was powered by a single high voltage neon transformer, it would be considered a listed section sign made up of five sections (see figure 3). Photo 5


Photo 5. Typical neon transformer enclosure (WP) that is marked as a section of an overall listed section sign

Each section would require a listing mark that identifies it as a section of the overall listed sign, including the transformer or power supply (see figure 4 and figure 5). When these listed sections are field-installed and secondary wiring is connected from the transformer to the individual sections, field inspections are required.

The listing of a section sign does not cover conformance assessment of the field-installed wiring and connected wiring. This must be inspected for compliance with any manufacturer’s installation directions in addition to with the NEC rules and any applicable local requirements. This is the responsibility of the electrical inspector. Additional information on section signs can be found in the UL General Information Directory in category (UXYT). Many inspectors hang their hats on the listing marks, but be careful; where the marks are listed section sign marks, field-installed secondary wiring must be verified for compliance also. Think of this inspection just the way a listed appliance is field wired. The inspection includes verification of the wiring and other connections to the equipment. The listing of the appliance does not cover the wiring in the building that supplies it.

Field-Installed Neon Secondary Wiring


Figure 5. Figure shows the listed individual sections of the overall section sign and indicates what is covered by the product standard and what is required to be field inspected for comformance

Article 600 is made up of roughly four pages of rules. Part II of the article includes the requirements for field-installed skeleton tubing, but also should be applied to all neon secondary circuits. Part II of Article 600 is where the minimum Code rules for high voltage secondary circuits, neon tubing, and electrode receptacles and enclosures are located. A hole in the 2002 Code has been identified in Article 600. A closer look at Part II and, specifically, Section 600.30 clearly indicates that this part of the article applies only to field-installed skeletal tubing. This is a major problem that requires a change to resolve what Part II is intended to apply to. There are many neon installations that include high voltage secondary field wiring that are beyond installed skeleton tubing installations. This part of the article should be applicable to all neon secondary wiring that is external to a sign body. This would include not only listed neon electric section signs, but also the other varieties of neon tubing and sign installations that are beyond just field-installed skeletal tubing.

The definition of skeleton tubing is clearly an indication that this part of the article was intended for application to more types of neon secondary circuits and not limited to just secondary circuits for field-installed skeleton tubing. Clearly the scope of Article 600 (Section 600.1) would also indicate that Part II should be applicable to these types of installations. Part II should apply to all neon signs or applications with field-installed high voltage secondary circuits such as reverse pan channel neon signs, hanging neon signs with field-installed high voltage secondary circuits, as well as others. In actuality, it is being applied to many of these installations in practice in the field by those performing these inspections.

Inspectors using special permission (as indicated in 600.3) to approve an installation need to be able to apply the provisions of Part II for high voltage neon secondary installations because this is the only location within the article to find the rules for tubing, high voltage secondary wiring, and electrode connections. Currently, under the 2002 NEC, Part II is applicable only to field-installed skeletal tubing. There have been several proposals to revise the NEC for the 2005 cycle. There also were proposals to clarify the applicability of Part II and resolve the conflict. The problem should be rectified in the 2005 NEC, but until that time there are the issues of rules that should apply to neon secondary circuits that literally cannot be applied as Article 600 is currently structured. Public comments are encouraged to help resolve the issue. The NEC provides an open consensus process that is open to all for proposals and comments to revise and improve the rules from cycle to cycle. The NEC is updated on a three-year cycle, which means a revision to correct this issue would not be included in the Code until the 2005 edition. There is a clear indication and need for interim action to clarify what is actually intended to be included under the requirements of Part II.

Summary

Electrical safety depends on installations meeting minimum rules of applicable codes and standards. Electrical signs and outline lighting installations fall under the scope of theNEC, specifically, Article 600. Jurisdictions that adopt the NEC, including Article 600, have a responsibility for inspections and approvals of electrical signs and neon lighting installations. The use of listed electric signs is a general requirement of Article 600 found in 600.3 and is also a general requirement of the Code and serve as a basis for approvals by electrical inspectors.

There are listed electric signs (self-contained signs) and listed electrical section signs. The sections of listed section signs are built to the same safety standard (UL 48) as listed self-contained signs. The key difference is that the listing of the electric sign sections applies only to each section. The wiring connected to the transformer primary and the field-installed high voltage secondary wiring is required to be inspected in the field for compliance with the manufacturer’s instructions as well as the installation rules of the NEC. The listing of listed section signs covers only the sections, not the field wiring. Listed equipment serves as a basis for the overall approval addressed in 110.2.

The AHJ has the authority to approve and also reject installations whether listed or not. Generally, inspectors are looking for the listing as a basis for the approvals, but inspection of the connections and field wiring is needed. The listing agency cannot assure that the installation instructions for field wiring have been followed and that it meets the requirements of the installation Code. This is the electrical field inspector’s responsibility.

Education and communication are two key elements in making effective electrical sign and neon inspections. Inspectors that are unfamiliar with neon, how it works, and how the Code applies to it, must bring their knowledge up to minimum levels to ensure quality inspections of these installations. There are resources available for this type of education and training. The new IAEI book, Neon Lighting, is sure to assist many as a valuable resource in this area. If unsure about any electrical installation or system and how the rules of the Code apply, it never hurts to ask in this business.


Read more by Michael Johnston

Tags:  Featured  May-June 2003 

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The Electrical Code in New York State

Posted By Mark Anderson, Thursday, May 01, 2003
Updated: Thursday, February 14, 2013

The information in this article is applicable to New York State but does not apply to New York City, which has its own building code.

A New Old Electrical Code for New York

In New York State, the promulgation and maintenance of the New York State Uniform Fire Prevention and Building Code is the responsibility of the Department of State. Until January of this year the New York State Uniform Fire Prevention and Building Code was a document prepared and maintained entirely by state agencies. Many of the code requirements relied on referenced standards. While the electrical code requirements for New York were found in Article 11 Parts 1030 through 1033, most of the details for code compliance relied on reference standards 51 through 53 which included NFPA 70–1993, the National Electrical Code. It is important to note that this standard has never been adopted as law in New York State. The standard is a means of complying with the code, that is, the Fire Prevention and Building Code of New York State.

In 1998 the state began the process to utilize the International Codes as the basis for the text of the New York State Uniform Fire Prevention and Building Code. The result is a new Uniform Fire Prevention and Building Code which incorporates and modifies the text of seven of these codes including: Residential, Building, Plumbing, Mechanical, Fuel Gas, Fire, and Property Maintenance. These seven codes with modifications for New York State now comprise the New York State Uniform Fire Prevention and Building Code. The earlier code was included as part of Title 9 New York Codes Rules and Regulations whereas the current code is now included in Title19 New York Codes Rules and Regulations (author’s emphasis).

Title 19 Part 1221.1 includes the Building Code of New York State (BCNYS). BCNYS Chapter 27 includes the electrical requirements. Section 2701.1 refers to NFPA 70–1999 for specifications to meet the building code requirements.

Title 19 Part 1220.1 includes the Residential Code of New York State (RCNYS). This volume regulates the construction and modification of one- and two-family homes as well as townhouses, three-stories or less in height. This volume includes Part VIII Chapters 33 through 42 which is essentially an electrical code for dwellings regulated by RCNYS. These chapters were produced and are copyrighted by NFPA and are based on the 1999 edition of their National Electric Code. These requirements are consistent with that standard and, indeed, that standard may be used in lieu of these chapters or when these chapters do not provide sufficient detail. But it should be noted that the 1999 edition of the NEC is not a code in New York State, it is a reference standard.

Enforcement

The administration and enforcement of the New York State Uniform Fire Prevention and Building Code is the responsibility of local government in New York. Each county, city, village and town is required to provide for enforcement of the state code. Most municipal code enforcement agencies rely on third-party inspection agencies—New York Board of Fire Underwriters, Atlantic Inland, Middle Department Inspection Agency, to name a few—to determine code compliance regarding electrical installations. Although these private inspection agencies are permitted to do inspections, the responsibility for code compliance and enforcement still rests wholly with the local government.

The private inspection agencies, almost without exception, require their inspectors to use the most current edition of the NEC. This practice is not consistent with the requirements of the New York State Uniform Fire Prevention and Building Code. Today the requirements are taken from the 1999 edition. Furthermore, if a contractor is wiring a single or two-family residence, the third-party inspectors should be checking the installation based on RCNYS rather than NEC, even though there is consistency.

One of the big differences between the old and new codes in New York State is the inclusion of many details and specifications within the new codes rather than the old method of reliance on reference standards.

The Future

The New York State Uniform Fire Prevention and Building Code relies on the 2000 International Codes and the 2001 Supplement. The New York code will be updated on a three-year cycle that is consistent with the revisions of the International codes. The State Codes Council, its technical subcommittees and the Department of State will monitor and participate in the International Code process. They will also make such revisions to the base codes as will be in the interest of the specific conditions and concerns within New York State. The relationship between the International Codes Council and the National Fire Protection Association is of great concern to all public safety professionals. What will become of the electrical requirements within New York State depends greatly on the code development process as it is played out in both the private and public sector. In summary, it is important to understand the relationship of NFPA 70 to the codes of New York State and to be aware that NFPA 70–2002 is not the standard in New York.


Read more by Mark Anderson

Tags:  Featured  May-June 2003 

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Near Misses Are Too Risky

Posted By Richard Owen, Thursday, May 01, 2003
Updated: Thursday, February 14, 2013

During your career as an electrical inspector, have you ever received a shock while inspecting? Have you ever accidentally faulted a circuit between phases or to ground? Have you ever tripped over something on the floor in a construction site because your attention was focused elsewhere?

Most inspectors who have been "in the business” for any length of time can answer yes to all the questions above, plus probably add other stories of near misses while inspecting. Inspectors are usually at a disadvantage when going onto a jobsite for inspections, their time on the jobsite is limited, and they are not that familiar with the physical layout and potential hazards. For example, all the workers on the site know that the forklift driver is a maniac, but the unsuspecting inspector may find out the hard way! Many times, the inspector is moving through the site and not paying attention to where he or she is stepping, concentrating on looking at the job. This leaves the inspector open to tripping and fall injuries that other workers would know to avoid.

Another problem the inspector often encounters is that when he or she arrives for a final inspection, usually all the equipment is closed and energized. This requires the inspector to either open the equipment for inspection while "hot” or de-energize the equipment. In many cases, turning the power to the equipment off is not a popular option, since the equipment may already be in operation, and "you just can’t shut us down!” To cut the power to a floor of personal computers in an office for your inspection does not score points for the inspector or the employer. Usually after a few calls to the mayor, it is made fairly clear to the inspector that de-energizing the equipment for inspections at one of the businesses in town is not a wise career move! This is not to say the inspector should not de-energize equipment before inspection, but just that outside pressures may encourage the inspector to risk injury from live equipment.

The electrical inspector may be well equipped as far as National Electrical Code (NEC) information goes, but how many have the proper personal protective equipment (PPE) available to them, and how many actually use that equipment? This equipment goes beyond the usual hard hat, safety glasses and maybe even hard-toed shoes the average inspector wears. Back in the "dark ages” when I was an electrical apprentice, the inspector showed up on the job with a sport coat, tie and street shoes. While I was impressed at the time with the sartorial splendor of the inspector (and maybe that’s one of the subconscious reasons I became an inspector— I get to dress well), the inspector was really not equipped to be touring a jobsite with any measure of personal safety.

If you work for an inspection agency, your employer probably has the legal obligation to ensure you are a qualified person as described in Article 100 of the NEC, and that you not only know the operation of the equipment, but also that you have received training on the safety hazards involved. In the case of an electrical inspector, this training probably cannot be on specific equipment, since an inspector sees so many different types, but he or she should at least be aware of the basic requirements for PPE when on the job. Whether you work for an inspection agency or are a contract inspector for a jurisdiction, you are the ultimate responsible party to ensure your own safety on the job.

One good source of information on workplace safety is NFPA 70E Electrical Safety Requirements for Employee Workplaces. This document has a section which gives guidelines on safety-related work practices, and even if your local government does not adopt NFPA 70E, it has excellent recommendations to help ensure your own workplace safety. Another source of information is OSHA, who may have additional requirements, possibly on a state level. In my home state, Minnesota, the state enforces Federal OSHA regulations, plus may enact further requirements that even the electrical inspector is required to follow when on a construction site. An example would be on a construction site or a large campus-type industrial installation, when a worker is around vehicular traffic of any type (such as the maniacal forklift driver mentioned above) no matter what the speed of the traffic, the worker must wear a Type 2 safety vest. This vest is of an approved safety color and has a certain minimum area of reflective material. If the worker (or inspector) deals with electrical installations, this vest must also be of an approved flame-resistant (FR) material that will not easily ignite if it is exposed to a flame or electrical explosion.

Electrical explosions, or arc-flash and arc-blast are now being recognized for the hazards they really are. Section 110.16 of the 2002 NEC requires a field-installed label on non-residential switchboards, panelboards, industrial control panels and motor control centers indicating to anyone approaching this equipment that they are subject to arc-flash injuries if they try to work on this equipment. There is information available from several sources on how to determine the possible force that could be expelled from the equipment in case of a fault. The amount of energy depends on the size and type of overcurrent device ahead of the equipment plus the available fault current at the terminals of the equipment. This force is expressed in calories per centimeter squared, and will obviously vary not only on the fault current, but also on how quickly the overcurrent device will open under fault conditions. An overcurrent device that opens in ½ cycle should limit the expelled energy better than a device that takes one or two cycles to open. The possible amount of energy that could be released will determine the level of PPE an inspector should be wearing to approach this equipment. In the past, inspectors have probably been able to inspect live installations with a minimum of protective gear, but as insurance rates continue to increase the facility owners will probably require the inspector to wear the proper level of PPE in order to limit their liability in case of an accident. This PPE could include a face shield, voltage-rated insulating gloves (even on installations under 600 volts), and Nomex® clothing including a hood (fondly known by the wearers as a "sauna suit”). Inspectors and electricians from the "old days” might be amused to see what the inspectors and electricians of today should wear on the job, but there is a much better chance of today’s personnel avoiding injuries or death from electrocution or arc-flash.

One other important aspect of inspector safety is the inspector’s risk going into a house or business and having no way of knowing how he or she will be received by the occupants. Even law-abiding citizens don’t cheer "Hooray! The inspector’s here!” when you show up. There are many other citizens who have real or imagined grudges against the government, and then here comes the inspector representing this "government.” The inspector then tells these people that they have to let him in so he can inspect their own personal property that is their "castle.” After the inspection, the inspector tells them what is wrong and that it is going to cost more money to fix all the problems he found. No wonder we often encounter people who threaten bodily harm to the inspector just out doing his or her job!

My city had a tragic incident a few years back on Christmas Eve when a housing inspector called on a problem property owner to again investigate a complaint of a trash-filled yard. When the inspector walked into the backyard to photograph the trash for evidence, the owner came up behind him and killed the inspector with a gunshot to the back of the head. The killer was caught and pled guilty, but that was small comfort to the inspector’s family, friends and co-workers.

Hopefully, this is an isolated incident and will never be repeated, but the inspector needs to be constantly aware that there are unstable people out there who are angry enough to resort to violence against a person just doing his or her job. Since having a police officer follow you everywhere is impossible, the inspector needs to be very aware of his or her surroundings and if a person becomes hostile, either attempt to defuse the situation or leave and return another time. If this person has a history of hostility, this information should be available to all inspectors who might have occasion to visit this property. An inspector should not hesitate to ask the local law enforcement to accompany him to these properties when an inspection is necessary. Our local police have always been willing to assist when necessary, but it is up to the inspector to be smart enough to ask for the help, instead of just trying to "tough it out.” Even though a person does not welcome the inspector with open arms, he is still entitled to the inspection he paid for, and that the work is done properly and without hazard.

National Electrical Safety Month is a good chance to remind the general public of the hazards of electricity. Electrical inspectors are a vital part of that electrical safety, but every day of the year inspectors also have to remind themselves that they need to use safe practices during the course of their job.


Read more by Richard Owen

Tags:  Featured  May-June 2003 

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Electrical Wiring – 2002 CEC Revisions

Posted By Leslie Stoch, Thursday, May 01, 2003
Updated: Thursday, February 14, 2013

As expected, the 2002 Canadian Electrical Code contains some changes in the rules for wiring. Most of the new requirements are beneficial, in that they make some new products available or provide new applications for existing products without affecting electrical safety overall. This article reviews a few of the more meaningful changes in 2002.

An enhanced requirement, Rule 12-012(11) now stipulates that conductors underground have a "suitable marking tape buried approximately halfway between the installation and grade level,” or have some other means to identify their locations and depth. This requirement is much more specific than the previous rule, which only asked for "adequate marking in a conspicuous location.” The new rule is more precise. The earlier one could have been interpreted in several different ways. This helps to reduce the risks when digging or excavating.

The uses of electrical nonmetallic tubing have been expanded. Previously, Rule 12-1502(2)(d) specifically prohibited using this material without mechanical protection. New Rule 12-1500 permits it to be used when "exposed where not subject to damage and in compliance with Rule 2-128.” An Appendix B reference to Rule 2-128 shows that nonmetallic raceways, when exposed in buildings of noncombustible construction, must have a minimum FT-4 flame spread rating and a maximum .625 square millimeters cross-sectional area.

Earlier versions of Rule 36-100(2) excluded electrical metallic tubing installed in buildings for circuits above 750 volts. Rule 36-100(2) now includes EMT in the list of acceptable high voltage wiring methods. I’m baffled as to why this change came about, since it does nothing to improve electrical safety at higher voltages and may even increase the risks.

The 1998 Canadian Electrical Code, Rule 12-2202(2) for cable tray installations specified that "The maximum design load and associated support spacings shall not exceed the values specified in Table 42.” This table provided maximum design loads and support spacings for cable trays. The new Rule 12-2200(2) now prescribes that maximum loads and support spacings be obtained from the cable tray manufacturer. As expected, Table 42 is deleted from the code —a more practicable approach to cable tray installations.

For many years, Rule 4-028(1) required that all insulated neutral conductors up to 2 AWG "be identified by a white or natural grey covering.” As an alternative, Rule 4-030 permits neutral conductors larger than 2 AWG "to be suitably labelled or otherwise clearly marked at each end.” New Sub-Rule (4) has been added to Rule 4-028, allowing neutral conductors in multiconductor cables to be identified by "painting or other suitable means” where accessible as long as the manufacturer’s markings are not obscured. This would apply to cables of any size.

There is also a new requirement under 4-028(1)(a), that the neutral conductor covering must be white or natural grey when installed in a service raceway for low voltage services up to 200 amperes. This would imply that if one used a 3/0 AWG neutral conductor (larger than 2 AWG), it would need to be white or natural grey. In this case, painting or taping would be unacceptable, even though it’s larger than 2 AWG.

A 1998 code requirement in Rule 36-100(4) made it necessary to provide permanent markers to identify the locations of high voltage cables in concrete or masonry, set into walls, floors or ceilings. Rule 36-100(4) now specifies that these markers be spaced no wider that 3 meters apart. These changes are beneficial, designed to minimize risks when drilling or otherwise inadvertently making contact with dangerous, high voltage wiring and the predictable results.

Rule 12-314 now requires that trestles that support wiring over buildings "”be constructed to bear the mechanical force of the conductors.”" Such forces should include the weights of the cables as well as short-circuit forces. The previous rule only required that trestles be constructed "of steel or other suitable material.”

Rule 18-156 introduces a new type of cable, type CIC (non-armoured control and instrument cable) now acceptable in cable tray in a Class I, Zone 2 hazardous location. The conditions for such use are that cable must have a minimum 300-volt insulation rating, the maximum circuit voltage is 150 volts and the maximum loading is 5 amperes.

In past codes, Rule 32-202 (a) and (b) required that fire pumps be wired in either metal raceways, armoured cables or metallic sheathed cables. Subrules (c) and (d) have been added to also permit rigid nonmetallic conduit and electrical nonmetallic tubing "embedded in at least 50 mm of masonry or poured concrete.” Rigid nonmetallic conduit is also permitted underground.

Rule 12-3034(1) Wiring Space in Enclosures still generally requires that electrical equipment enclosures not be used as junction boxes, troughs or raceways for wiring feeding through to other equipment. But this rule opens a new door by introducing two interesting exceptions:

a) When tapping a feeder to other electrical equipment when there is a separate lug for each tap conductor, the lugs are accessible and no more than 75 percent of the available equipment wiring space is used.

b) Electrical equipment may also be used as a raceway in an existing installation as a feed through to other equipment when no more than 40 percent of the cross-sectional wiring space is filled.

As with past articles, you should always consult the electrical inspection authority in each province or territory as applicable for a more precise interpretation of any of the above.


Read more by Leslie Stoch

Tags:  Canadian Code  March-April 2003 

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Celona Story on Rhode Island’s Co Bill

Posted By John Celona, Thursday, May 01, 2003
Updated: Thursday, February 14, 2013

All of us have been horrified in recent years to hear of the many deaths from carbon-monoxide poisoning in Rhode Island, especially in the winter months when homes aren’t as well ventilated as they are during warmer weather. Carbon monoxide is the leading cause of death by accidental poisoning in America.

This silent, odorless killer can leak from furnaces, ovens, chimneys, and gas-powered clothes driers. Even appliances that work properly can produce unsafe levels. Exposure can kill you, and even low-level exposure over time can make you sick.

All these deaths could have been prevented if we had the legislation and education in place to help people learn about the dangers of carbon-monoxide poisoning. That’s why I introduced legislation in 2001 to require carbon-monoxide detectors in certain homes. On January 1, 2002, the new law went into effect in Rhode Island, requiring that carbon-monoxide detectors be installed in all new homes with gas utilities and other homes up for sale. This law, the first of its kind in the nation, will help save lives.

Here’s what the law now requires:

All newly constructed residential dwelling units with gas utilities, and all dwellings converted to residential units before 1976, must have at least one carbon-monoxide detector that is UL listed or approved by a nationally recognized testing laboratory approved by the State Fire Marshal.

A carbon-monoxide detector must be placed outside each sleeping area in the immediate vicinity of the bedrooms.

Each bedroom or sleeping room separated from another by "other use areas,” such as kitchens or living rooms, but not bathrooms, must have a separate carbon-monoxide detector.

All carbon-monoxide detectors must be mounted according to the manufacturer’s specifications.

All carbon-monoxide detectors must have a visible, intermittent or steady "power on” indicator and, in case of gas detection, sound an audible signal having a minimum rating of 85 dBA at 10 feet.

Applicable dwelling units cannot be sold or transferred without the installation of carbon-monoxide detectors and certification from the office of the State Fire Marshall or local fire department that the law has been complied with.

If you have questions about this law or about carbon monoxide detectors, call the State Fire Marshal’s office at (401) 294-0861.


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Tags:  Featured  May-June 2003 

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Performing Arc-flash Hazard Calculations

Posted By C. M. Wellman, Thursday, May 01, 2003
Updated: Thursday, February 14, 2013

An arc flash is a potentially very hazardous event, in which the heat energy alone can cause ignition of clothing and extensive severe burns. The other affects of the arc flash can also cause severe injuries. The effects of an arc-flash injury can be life changing and the costs can be staggering. One utility company recorded three serious arc-flash injuries in a three-year period. Costs to date for medical, indemnity, and vocational retraining are $875 k with additional funds in reserve. Another company, a manufacturer, has reported it has experienced an average of 2.2 arc-flash injuries/year over the last ten years. The effects on people have included children not recognizing a parent, family breakup, depression, hearing and vision damage, and the need for extensive skin grafts. People must have protection from this hazard for their employer to meet OSHA requirements.

Potential hazards from electricity include electrical shock and arc flash. Electrical shock occurs upon contact or approach within the breakdown distance of an exposed, energized electrical conductor or circuit part. Arc flash occurs during breakdown when the arc current exceeds the glow-to-arc transition current. The arc current creates a brilliant flash of light, a loud noise, intense heat, and a fast moving pressure wave that propels products of the arcing fault. Products of the arcing fault, all stemming from the sudden and violent release of electrical energy, include ionized gases, metal vapors, molten metal droplets and shrapnel.

Photo 1. Investigation of an arc-flash incident


Photo 2. Arc-flash test case

NFPA 70–2002, National Electrical Code,2 requires that electrical equipment be marked in the field to indicate where an arc-flash hazard exists. NFPA 70E, Electrical Safety Requirements for Employee Workplaces,3 requires an arc-flash hazard analysis. In order to identify this equipment and determine the extent of the electrical hazard from the arcing "fault” current, an arc-flash hazard analysis must be performed by an experienced engineer or trained technician specialist.

Conducting an arc-flash hazard analysis has been, and is, very difficult. Not enough testing had been done to develop models by which to accurately represent all the real applications. Previous methods of calculating incident energy were limited to arcs in open air or to arcs in boxes (enclosures), 600-V and below, between the range of 16,000 to 50,000 amperes. NFPA 70E–2000 contains the best methods,


Photo 3. Arc-flash test setup

of determining arc-flash hazard conditions, known at the time of its writing. Its contents regarding arc-flash hazard calculations were based on technical papers by R. H. Lee, "The Other Electrical Hazard: Electrical Arc Blast Burns,” and by R. L. Doughty, T. E. Neal and H. L. Floyd, "Predicting Incident Energy to Better Manage the Electric Arc Hazard on 600-V Power Distribution Systems.”4

The arc-flash hazard calculations included in this guide enable quick and comprehensive solutions for arcs in single- or three-phase electrical systems, either of which may be in open air or in a box, regardless of the low or medium voltage available. Generally only systems with a supply transformer rated 125 kVA and larger are considered as having possible arc-flash hazards. Designers or facility operators can use the IEEE 1584–2002 to determine the arc-flash hazard distance and the incident energy to which employees could be exposed during their work on or near electrical equipment.


Photo 4. Wrap around face mask shown with other protective wear

As could be expected, higher magnitudes of arc current flow or longer duration of arc current flowing just intensifies the explosive forces of the sudden and violent release of energy. D.R. Doan and R.A. Sweigart showed that the results of the calculations vary over a wide range in their recent IEEE technical paper titled "”A Summary of Arc-flash Hazard Calculations.”"5 In this study of 33 plants with 4892 buses or switching points under 600 volts, the median incident energy was only 2.1 cal/cm , but many buses had quite high incident energy levels:

24% of buses over 8 cal/cm2

12% of buses over 40

5% of buses over 85

1% of buses over 205


Photo 5. PPE for high level exposure

These very high incident energy levels cause the most severe injuries. The protection provided by following the default tables in NFPA 70E will not provide adequate protection for the hazards presented in these cases. Only an arc-flash hazard analysis can identify these buses or switching points and allow providing protection or taking steps to reduce the energy level.

Determining incident energy and the arc-flash boundary involves following a process. There are several steps in an arc-flash hazard analysis:

1. Get a single line diagram and identify buses and switching points of concern. List modes of operation so separate calculations can be done for each — one/two utility supplies, operation on generators, secondary ties open/closed.

2. Find the bolted fault current at each bus for each mode of operation and determine how much of it will flow through the protective device that will interrupt the fault — deduct the fault current generated by motors and that comes through an alternate supply.

3. Calculate the arcing fault current in the protective device using a 1584 calculator. Not needed for certain fuses and not needed if using circuit breaker shortcut method.

4. Find the clearing time for the protective device from the time-current curves. See manufacturer’s web site if curves have not been drawn and a computer program is not available. Two seconds is commonly taken as the maximum time for a person to get out of the way.

5. Enter all data into the 1584 calculator, including grounding type, equipment class, protective device type, and the distance a person might stand from the possible arc.

6. Review data for reasonableness and select PPE.


Photo 6. Cubicle following arc-flash

Many types of personal protective equipment are available. Many organizations select an everyday work uniform for electricians and others who frequently operate electrical power equipment. The clothing may consist of inherently flame-resistant (FR) fibers such as aramid fibers or it may use flame-resistant treated (FRT) cotton fabric. There are significant differences in long-term value for each of these fabrics. Aramid garments are typically priced higher than FRT cotton but have a significantly higher durability than treated cotton, lowering the life cycle cost. In addition, flame-resistant protection is carried in the chemistry of the fibers whereas with FRT cotton, the (FR) treatment can be lost in laundering or wear. Photo 4 and Photo 5.


Photo 7. Outdoor gear following arc-flash

R pants are required with any type of upper body protection. NFPA 70E and OSHA also require face and head protection and that can be provided by hoods or by face shields plus a balaclava. Leather gloves or voltage-rated gloves provide good hand protection. Leather or rubber boots provide foot protection. PPE selected involves a compromise between providing protection and allowing manual dexterity, vision, and hearing with minimal thermal stress. Following IEEE 1584 and NFPA 70E is the way to optimize the selection.

When the calculations are complete, you can review the levels of PPE for all the buses together. Recognize you can go to the reference tables page and change the levels to match changes in NFPA 70E or to match your supplier’s PPE ratings. Select a minimum number of levels for the particular facility, reset the levels to match, and rerun the calculations.


Photo 8. IEEE Guide for Performing Arc-Flash Hazard Calculations

IEEE 1584—2002 results have enabled users to recognize that some electrical systems have such high incident energy levels that additional design features, such as having suitable and readily accessible disconnecting means separate from equipment to be worked must be included, or work on or near such high risk areas can only be performed under de-energized conditions. Users of IEEE 1584 should be aware that it does not enable them to address aspects of arc-flash hazards other than incident energy. Photo 6 and Photo 7.

When you have completed your calculations, you need to review them to see if engineering or operating changes are needed. As shown above, it is common to find some buses with an incident energy over the 40 cal/cm that is considered safe for work with PPE. In those cases no work should be done with equipment energized, even with switching equipment doors closed. Engineering options include:

  • Replacing switchgear with arc-resistant switchgear
  • Adding a secondary main relay that can trip a primary circuit breaker
  • Adding zone interlocking in switchgear: A signal from a downstream circuit breaker blocks an upstream circuit breaker from tripping. The upstream CB can be set quite fast in this case.
  • Changing fuse type: For under 600 V cases, perhaps going to a current-limiting fuse. For higher voltages, perhaps going from a current-limiting fuse to a noncurrent-limiting fuse.
  • Adding differential relays

Operating options include:

  • Adding provision for remote racking and remote operation
  • Getting a racking wrench that has a long handle, which increases the working distance
  • Changing the sequence of switching operations to reduce the time when exposure is high.

Read more by C. M. Wellman

Tags:  Featured  May-June 2003 

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Homeowners Warned About Aging Home Electrical Systems

Posted By Michael G. Clendenin, Thursday, May 01, 2003
Updated: Thursday, February 14, 2013

Owners of older homes may have a much more alarming problem than peeling paint and loose floorboards lurking behind their walls. According to the latest statistics from the National Fire Protection Association (NFPA), electrical distribution was the largest cause of property damage wreaking $643.2 million in property damage in home structure fires, and the third leading cause of home structure fires, causing 40,400 fires, the second leading cause of death (329) and third leading cause of home fire injuries (1,357) between 1994 and 1998, the latest data available.

According to the latest statistics from the U. S. Consumer Product Safety Commission (CPSC), household wiring also tied with small appliances as the leading cause of accidental electrocutions associated with consumer products. For this reason, the Electrical Safety Foundation International (ESFI) is urging homeowners to have their homes electrically inspected, particularly if they fall into one of the following categories:

  • owner of a home 40 or more years old;
  • owner of a home 10 or more years old that has had major renovation, addition or major new appliance; or
  • new owner of a previously owned home.

"If your home has dim or flickering lights, loose receptacles, circuit breakers that frequently trip or fuses that frequently pop, hot or discolored outlets and light switch cover plates, or damaged wire insulation, your home may well be a fire waiting to happen,” warned ESFI Executive Director Michael G. Clendenin. "That is your home’s way of telling you that you have a problem.”

ESFI also urges homeowners to know if their homes have aluminum wiring, and if so, to monitor it more closely. Because aluminum wire oxidizes more rapidly than copper wire, it presents a greater potential fire hazard; oxidation increases resistance and heat buildup along the circuit. Since aluminum wire expands and contracts at a greater rate than copper wire, there is also a greater likelihood that gaps could develop at connections, potentially leading to hazardous arcs and glowing connections.

Even in younger homes, new homeowners should take an active role in understanding the condition of the current electrical system, its capacity, limitations, and potential hazards. ESFI encourages homeowners to seek the assistance of an electrical inspector or a qualified, licensed electrician to inspect the home’s circuitry and ensure the home’s circuits are not overloaded and the home’s electrical service can adequately supply the demand. Homeowners are also encouraged to develop a detailed map of the circuitry showing which outlets and fixtures are served by which circuits and how much power is being demanded of each.

Clendenin says that electrical inspections can catch problems hidden behind the walls and correct them before they turn tragic. In many cases, technologies such as ground-fault circuit interrupters (GFCIs) and newer arc-fault circuit interrupters (AFCIs) can be installed to help prevent a fire and accidental electrocution. The bottom line is: Inspect and Protect — call a qualified, licensed electrician to schedule an electrical inspection.”

These and other electrical safety tips are available at the Foundation’s web site atwww.electrical-safety.org or by phone at 703-841-3229.


Read more by Michael G. Clendenin

Tags:  Featured  May-June 2003 

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Implementing 70E in the Electrical Construction Workplace

Posted By Robert McGregor, Thursday, May 01, 2003
Updated: Thursday, February 14, 2013

The development of NFPA 70E–2000 provides a roadmap for any employer to develop an extremely effective electrical safety program, which if followed, would most probably eliminate future electrical injury and fatalities. I believe there would also be a side benefit of increasing both management’s and their electricians’ overall safety awareness of other hazards as well. Many electrical contractors have both real financial roadblocks and misconceptions that are impediments that hinder implementation of many components of 70E. The roadblocks of misconceptions consist of: perceived costs associated with implementation, such as special equipment and hours of employee training; acceptance and willingness to implement the program by their electricians; and the horrific belief by both management and electricians that shock, injury, and fatalities are just part of the job and only those who are careless or lack skills suffer the fate of injury.

At the 2003 IEEE IAS Electrical Safety Workshop, several statistics provided by Dr. Mary Capelli-Shellpheffer indicate just how much of a problem we face in eliminating just electrically caused injuries. Between 1992 through 1998 there were 32,309 non-fatal electrical injuries, and in 1999 there were 278 fatalities from contact with electrical current and 216 from fire and explosion in construction alone. Financial costs of one electrical injury example cited was: $650,000 of initial medical treatment which included five major surgeries, $250,000 for five repeat admissions for reconstructive surgery, and $250,000 for five years of rehab of over 100 patient visits. (One cannot imagine the emotional costs or the pain that the injured individual has gone through and is going through even now.) The company had an additional $350,000 of direct costs. Multiply the total of $1,500,000 by your choice of recognized factors for indirect costs (between 3 and 8). How does a company recover from costs such as these?

If one does a root cause analysis on any injury or fatality, the bottom line is almost always human error by the victim or by another, and the injured individual was the event that occurred just before the incident. The human error factor can be either eliminated or its probability significantly reduced to almost zero potential of occurrence through exerting as much diligence in achieving safety as in obtaining and doing the work. The axiom "Work must be part of the safety environment” instead of "Safety is part of the work environment” must be the company’s attitude. NFPA 70E provides the framework to establish the safety environment.

Whether management is willing to accept it or not, improper management is always a significant factor that is revealed in a root cause analysis. Those management factors that are most often delineated are: failure to provide proper training; failure to provide proper procedures; failure to provide proper tools for the job; failure to provide proper protection; failure to recognize the potential for a hazard; failure to correct or eliminate improper behavior and work practices by employees; and last but not least, the all encompassing failure to provide a safe place of employment.

The electrician contributing factors are just as serious: failure to follow training that was provided; failure to follow proper procedures; failure to utilize proper tools; failure to practice safe behavior; failure to recognize the hazard; and failure to create a safe work environment for one’s self and others.

Both sides share one common factor, which is the failure to acknowledge that there is a potential hazard. How often has one heard, "This is construction, there are dangers, just learn to live with it. Only those that are careless and don’t pay attention get injured!” Electrical hazards are different. Sure, we can see that the extension cord is damaged, but it still works and we think, "I’ll fix tomorrow.” We cannot see electricity or the power it possesses, so we ignore the hazard. We cannot see the wrench inadvertently left in the panel by the previous person to work on it, so we ignore the potential for hazard when the bolts are removed to service an electrical panel. There is also a belief held by many electricians that if an arc flash occurs, they can jump out of the way (physically impossible), much like if they see an object falling off a scaffold, they can jump out of harm’s way. If there is an electrical incident, most people will not acknowledge that their actions or lack of actions; the ignored work conditions; their past training; or lack of training were major contributing factors in getting injured or causing the incident to occur. When an individual completes his or her apprenticeship and is given journeyman status, there is a major misconception that he/she is now qualified for any kind of electrical work, when in fact, just like any profession, the learning process is just beginning and is a continuous process. The basics are usually present but not the learning that experience brings. In many cases, the on-the-job instructor taught his unsafe shortcuts to the apprentice, just as they had been taught to him. There are still practicing electricians who will test for voltage on 220-V AC and lower by "walking the panel with thumb and finger.” Or how about the practice of wrapping the shaft of the screwdriver with electrical tape to insulate it so they will not get shocked? Or even worse, is the instruction of the left hand rule for disconnects. We acknowledge the potential for the disconnect to blow-up and best procedure we can instruct an electrician to do is to risk you’re his or her left hand to serious injury! We all know of other unsafe practices that are still being done today and passed down to a younger generation. We do not acknowledge the hazards because it would mean a 180-degree change of how things are done.

Over the years of the changing work environment of compressed building schedules, productivity demands on every trade, higher current levels in use coupled with new and improved electrical components, and pressures to do more with less all combine to increase pressures on the individual electrician as well as on the contractor. The last thing a contractor wants is another set of perceived untested and unneeded regulations that he believes will slow down production and cost money. Many contractors, to this day, believe that OSHA regulations have cost them money and have slowed down productivity. Many electricians I work with believe that wearing personal protective equipment (PPE) required by OSHA regulations increases the likelihood of their getting hurt because of increased risk-taking, instead of protecting from something they have only heard about others getting hurt from. Many electricians also believe that utilizing PPE is more dangerous because of the increased difficulty in performing tasks. In reality, however, it is usually due to improper fit, improper training or, at the worst instance, the hazard was not engineered out to eliminate the need for the PPE.

The decision to implement electrical safe work practices for your company begins by acknowledging that the problems discussed previously really do exist and that electrical injury or the potential for injury must cease. Management commitment for electrical safety must be absolute in the value of the program, not just from the potential for financial gain but from the humanitarian aspect. A zero tolerance for unsafe electrical work must be adopted, and defining what constitutes unsafe work is a major hurdle but it is concisely spelled out in 70E. The steps to be taken and the responsibility to make things happen must apply across all levels of your company. There also needs to be a careful analysis of whether outside help, an independent safety professional who is trained in electrical hazard recognition and mitigation, is going to be needed. Smaller contractors have safety as a part of their human resources department or someone that is doing the bookkeeping for the workers compensation. Larger contractors and organizations may have someone that may be skilled in OSHA regulations and/or has a safety degree, but it is rare to find individuals that understand the many consequences of electrical injury and what constitutes an electrical safe work practices program. In many cases a contractor has the 2-inch binder generic safety program purchased off the shelf or maybe an electrical trade association generated program that is collecting dust on the shelf. To establish an electrical safe work practices program will mean to discard many past beliefs, practices and programs and perhaps search out those who can provide proper guidance to develop such a program if the knowledge and ability is not in-house.

The process begins with an analysis of the types of electrical work in which the contractor engages. For instance, if the contractor is strictly a residential contractor working on a maximum voltage of 220 V, the electrical safety program requirements are quite different than for a commercial/industrial contractor. Do not think that just because your company’s work is residential that 70E requirements do not apply, for 70E does not specifically differentiate between residential, commercial, or industrial work; instead the hazard potential of the arc flash and shock are the determinants for work practices which are implemented. The safe work practices of 70E are drastically different from those in OSHA 29 CFR 1926 Subpart K. For example, the arc-flash hazard is not recognized in the construction standard because it was not even a recognized hazard by OSHA till the mid 1990s so there is no mention of PPE, use of voltage-rated tools or arc-flash hazard analysis. Also the extremely inadequate LOTO guidelines in Subpart K provide no guidance on what constitutes a safe lockout/tag-out procedure or program. A contractor that utilizes Subpart K as a guide for safe work practices is constantly placing its electricians in danger of severe injury or death. If Subpart K is an effective standard, then why are all the electrocutions and other electrical injuries occurring? Subpart K provides little guidance as to what electrical safety procedures are for the electrician other than 1926.416(a)(1): "No employer shall permit an employee to work in such proximity to any part of an electrical power circuit that the employee could contact the electric power circuit in the course of work, unless the employee is protected against electric shock by de-energizing the circuit and grounding it or by guarding it effectively by insulation or other means.” Yet the electrical contractor’s electricians are routinely told they cannot shut it down because of inconvenience to the customer; and, besides, aren’t electricians supposedly trained to work on energized conductors carefully and not get shocked!

NFPA 70E roadmap begins with a concept similar to OSHA, i.e., the employer provides the structure, equipment and training for safety and the employee, once trained by the employer, shall implement the safe practices [70E Part II, 1-3 Responsibility]. Developing the structure to implement the program is the first hurdle the employer has to cross. The safety policy will have to clearly state the practice of avoiding work on energized electrical conductors. If work on energized conductors is needed, an energized work authorization will have to be completed. The authorization will have to clearly identify reasons for the work and what procedures will be followed. NFPA 70E in Parts II through V have many of the safe work procedures explained, but also refer to other publications such as IEEE Standard 902 Maintenance, Operation, and Safety of Industrial and Commercial Power Systems and the NFPA Electrical Safety in the Workplace by Ray A. Jones and Jane G. Jones for other procedures. The structure for identifying and evaluating the skills of the electricians as well as providing the training necessary to equip them with the necessary knowledge for the work they will undertake is perhaps the most daunting component, next to actually doing the evaluation and making the financial commitment to conduct the training. The last hurdle to overcome initially is to provide the ability to obtain cooperation of the electricians to implement the program and encourage each electrician to be honest in self-assessment of his or her ability to do a particular job in addition to the management assessment. (Of course, an electrician is never asked to do a job prior to a hazard assessment!)

The evaluation and training will perhaps represent the largest financial outlay for a company, though the purchasing of equipment may appear to be the largest initial outlay. The training will usually necessitate a significant amount of time for which the electrician is not productive and still being paid so the cost is double the benefits normally paid. The training that is necessary is specific for the work to be done. The requirements are contained in Part II, 1-5: "…shall be trained to understand the specific hazards associated with electrical energy. They shall be trained in safety related work practices and procedural requirements as necessary to provide protection from electrical hazards associated with the respective job or task assignments. …trained in first aid and emergency procedures…” All the training is necessary to get the electrician to be a qualified person as outlined in 1-5.4.1, which is, in short terms, a person that can correctly identify and understand all the hazards associated with the task and knows how to keep himself and others in the area safe from injury, both from the aspect of how to avoid initiating an incident and what is mandatory for safety if an uncontrolled release of electrical energy should occur. The training is not going to be a one-time occurrence, but rather an ongoing lifetime of training to keep procedures current as technology changes. An electrician is expected to know everything about the job he is assigned to from the moment he starts, but the question is, is it a reasonable expectation? For example, just look at the number of types, and manufacturers of panels, disconnects, and motor control centers. Each type of unit has a specific point that the manufacturer has determined to be the best grounding point for application of the leads of a meter. Without the electrician being trained or given the information from the manufacturer on what is the manufacturer’s approved test ground point, the electrician risks obtaining an incorrect meter reading which could have disastrous consequences. It will be important to utilize an individual(s) that is competent to conduct the training and can keep the training current.

Most of the training will be for naught if the proper tools are not provided for safe work to occur. The proper tools such as voltage-rated tools and proper voltage testers will be needed as well as training for their use and care. Personal protective equipment, such as properly fitted voltage-rated gloves and FR clothing, which have been selected for level of potential hazard are also needed. Some items might be the type that could be utilized by several individuals at various times such as 30-calorie-and-above-rated suits, but others such as Class 00 and 0 gloves would be best served as personal equipment. The equipment has to be readily available when the electrician needs it for the work, not when the warehouse can deliver it to the jobsite. The equipment has to be appropriate for the task for the electrician to want to use it. To get a 100 ATPV rated suit because it can be utilized for a variety of exposures on different jobs is going to be shortsighted, because instead of making the sound financial choice to obtain several suits appropriate for the anticipated exposures developed from hazard assessments that several individuals could wear, they now have to worry about having a protective suit when it is needed at two different locations. Having only one or two suits will also limit who can use the suit due to size limitations. The electrician has to be instructed in the care and use of the equipment along with the equipment’s limitations. It is also important to have a supplier of the tools and PPE that is knowledgeable of the hazards that an electrician faces. The supplier needs to know how to best assist the contractor in selecting the best PPE by having a good understanding of the various ANSI standards that the FR clothing and tools must meet.

NFPA 70E is one of several extremely useful tools available to enable an electrical contractor to achieve an electrically safe workplace. The first step is the hardest. At some point we have to stop doing the same old thing of allowing electricians or other employees to perform tasks on energized conductors that could be easily de-energized. We have to end the belief that if they get injured, it was because they were careless or that risk to life and limb is just part of the job. The potential rewards are great for the company as well as for each employee. There is a saying "Realize that today is a gift that enables one to be present tomorrow.” Start today implementing NFPA 70E as the framework for your electrical safety program.


Read more by Robert McGregor

Tags:  Featured  May-June 2003 

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Some outlet boxes are sold with clamps packaged in bulk, rather than included?

Posted By Underwriters Laboratories, Thursday, May 01, 2003
Updated: Thursday, February 14, 2013

 Question: Outlet box

Some outlet boxes are sold with clamps packaged in bulk, rather than included in the box. The UL White Book and packaging requirements do not seem to prohibit this practice. Does UL address this issue?

Answer

UL Listed outlet boxes may or may not be provided with clamps. When clamps are provided, they are required to be already mounted in place or provided in the carton with the outlet box. If the outlet boxes are bulk packaged, the clamps may be in a separate bag, but are still required to be provided in the same carton. An exception to this requirement is applicable when the box is marked for use with a specific clamp. This marking shall include the manufacturer’s name, catalog number and the type. For more information about outlet box clamps, see the UL Guide Information for Metallic Outlet Boxes (QCIT) and Nonmetallic Outlet Boxes (QCMZ) located on page 81 and 82 respectively of the 2002 White Book.


 

Question: CE Mark

Is the CE Mark a safety certification mark?

Answer

No. The CE Mark is a European marking scheme that consists of the manufacturer’s declaration that a product complies with a European Directive. Generally, a manufacturer or its authorized representative "self- declares” that its product conforms to the applicable directive. A third-party certification organization may not have tested the product and certified that it complies with appropriate safety requirements.

The CE Mark is required on products in the 18 countries of the European Economic Area (EEA) to facilitate trade between the member countries. The CE Mark provides a means for a manufacturer to demonstrate that the product complies with a common set of laws required to allow free movement of trade within the EEA countries.

On the other hand, the UL Mark on a product indicates that the product has been evaluated by an independent third party and found to comply with applicable safety requirements in effect in North America and is suitable for installation and use in accordance with North American Installation Codes such as the National Electrical Code.

Unlike the UL Mark, the CE Mark:

  • is generally based on self-declaration rather than third party certification, and
  • does not demonstrate compliance to North American safety standards or installation codes.

A product that bears a CE Mark may also bear a third-party certification mark such as UL’s Listing Mark. It should be noted that the CE Mark and the UL Mark are not related since they are intended for different purposes. AHJs should look for the UL Mark on products to determine that a product complies with applicable safety requirements for North America. For more information about the CE Mark, visit UL’s website athttp://wsww.ul.com/regulators/CEmarkinfo.html/


 Question

Are there engine generators Listed to UL 2200?

Answer

There are several manufacturers that have a variety of stationary generators Listed under the category "Engine Generators” (FTSR). UL 2200, the Standard for Stationary Engine Generator Assemblies, is used to evaluate these generators. The UL Guide information is published on page 35 of UL’s 2002 General Information for Electrical Equipment Directory, the White Book. This category also appears in the 2002 Electrical Construction Equipment Directory (Green Book) on page 120 and also on UL’s Online Certification Directory atwww.ul.com/database.


 

Question: Gas- or oil-fired equipment

For gas- or oil-fired equipment such as a furnace with a "fuel gas appliance” label, has UL evaluated the electrical portion of the equipment?

Answer

When UL has certified these products, the electrical devices on the product are included as part of UL’s evaluation. The UL Gas-Fired Listing Mark has replaced UL’s Classification Mark that was previously used on gas-fired products. The Gas-Fired UL Mark on a product signifies that the product has been evaluated for both electrical safety and gas safety. For additional information concerning UL’s Gas-Fired Listing Mark, visitwww.ul.com/gas2/mark.html.


 Question: Photoluminescent exit signs

Are photoluminescent exit signs Listed or Classified?

Answer

Photoluminescent exit signs are Listed by UL in accordance with Supplement SG of UL 924, The Standard for Emergency Lighting and Power Equipment, issued July 11, 2001. Prior to January 2002, photoluminescent exit signs were UL Classified in accordance with UL 1994, as part of a floor-proximity path-marking system.

UL’s Classification program was discontinued, effective January 2002.

UL Listed exit signs are published in UL’s Electrical Construction Equipment Directory and in the Building Materials Directory under Self-Luminous and Photoluminescent Exit Signs (FWBX), and can be accessed on UL’s Online Certification Directory atwww.ul.com/database.

The requirements for photoluminescent exit signs in UL 924 are based on the installation requirements in NFPA 101 (2000 edition) Life Safety Code. These requirements state that photoluminescent exit signs are to be continually illuminated while the building is occupied, with the illumination type and intensity in accordance with the Listing information. During normal (i.e., non-emergency power) conditions, these exit signs function as externally illuminated exit signs and are subject to the 5-foot-candle minimum illumination requirement in NFPA 101. During emergency power conditions, photoluminescent exit signs provide their own illumination, similar to internally illuminated exit signs.

Tags:  May-June 2003  UL Question Corner 

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Inspecting Electrical Renovations

Posted By Frederic P. Hartwell, Saturday, March 01, 2003
Updated: Thursday, February 14, 2013

As buildings age, their electrical systems age with them. Renovating those older systems adds flexibility through modern wiring practice and increases safety. However, the electrical contractor and the authority having jurisdiction need to agree on the ground rules that will apply to the construction. This article has two purposes. First, it looks at some general principles of responsibility for National Electrical Code compliance in renovation projects, and then it takes a practical look at construction issues that often result in NEC application controversies during renovations. The NEC is not, by its own terms, retroactive. The extent to which it will be applied to an existing condition is left to the enforcing jurisdiction. Space does not allow this article to cover when existing defects must be corrected simply because the wiring has deteriorated, and not because a renovation contract has triggered an electrical permit and subsequent inspection. This is a separate topic involving other standards, such as NFPA 73, Electrical Inspection Code for Existing Dwellings.

Some Ground Rules

A word of caution is in order here. Do not view the principles that follow as legally binding or comprehensive, because enforcing jurisdictions can and probably will differ on the details. Instead, look at this discussion as a starting point for considering the types of issues to sort out between the inspector and contractor, preferably before the contractor has made a binding agreement with the owner as to the price and scope of work.

If regulations addressing these issues are not set out in writing ahead of time, the author strongly recommends enforcing agencies consider engaging in an appropriate rule-making procedure (hearings, formal vote by regulatory authority, and subsequent publication) to do so. The financial consequences for a contractor or for an owner can be substantial. If those consequences have the appearance of being arbitrary or capricious, or simply serving the special interest of the electrical trade, the potential legal and political ramifications may inadvertently destroy the technical independence of the inspection authority. Everyone loses from such an outcome.

Will rules for new buildings apply? There may be a threshold, such as a percentage of the building involved or a change of use category as covered in the applicable building code, beyond which the work is considered new construction. If this is the case, all wiring must meet the current NEC requirements that would apply in the same jurisdiction to new buildings.

Violations in other areas. If the work qualifies as a renovation, then areas of the building unaffected by the renovation may be exempt from compliance with current NEC provisions. For example, if the electrical permit application covers a living room and den, few if any jurisdictions would attempt to legally compel the provision of GFCI protection for unprotected bathroom receptacles elsewhere in the occupancy.

The actual work. The renovation work itself must usually comply with all applicable current NEC requirements. If the contractor (or inspector) believes otherwise, such as when a contractor seeks permission under 90.4 for an alternate procedure believed to offer equivalent safety, then the issue must be fully explored as soon as possible. Note that the equivalent safety provisions of 90.4 now are allowed only by special permission. This means that the inspectional authority will have to make a formal, written finding of equivalence, for which it may be held accountable subsequently. Such allowances require careful consideration.

Violations created by renovations. The renovation work usually will not be allowed to create a violation of the NEC in a supposedly unaffected portion of a building. For example, suppose a dining room and kitchen renovation changes the location of a doorway into the adjoining living room such that the receptacle placements in that room no longer comply with 210.52(A). The contractor and inspector would be well advised to discuss whether the receptacle outlets in the living room must be added or relocated accordingly.

Existing violations in renovated areas. There may be jurisdictional limits on whether an existing violation in the renovated area must be corrected. Some jurisdictions normally insist on this, and others do not. Some ask for corrections only if the renovation makes the existing problem worse. This topic must be fully explored between the inspector and the contractor ahead of time for two reasons. Considerable judgment may be required on the part of the inspector, and that judgment may have enormous financial implications. For example, 230.70(A)(2) now excludes service disconnecting means from bathrooms, but that rule is relatively recent. Many bathrooms, especially in nonresidential occupancies, contain existing service equipment. If such a bathroom were being reconstructed, the cost of relocating the service would probably dwarf the cost of all remaining electrical work.

Existing hazards.Most jurisdictions have a mechanism for compelling the correction of existing code violations that create a clear and present danger. If this is the case, the contractor needs to know whether this work must be included in the renovation, and upon whom the financial responsibility for corrections will fall.

Renovation Code Issues

Although some of the following issues frequently arise in new work, they come up so often in renovations that they deserve special consideration here.

Shallow boxes.At one time the NEC made distinctions between old and new work regarding the minimum allowable depth of a box, but no longer. Boxes must have a minimum depth of 1/2 in. Photo 1 shows a 6-cu-in., 4-inch-diameter ceiling pan without cable clamps. This is the smallest box permitted for Type NM cable because a single 14-2 cable, with its separate equipment grounding conductor, accounts for all of the volume1 [review 314.16(B)]. These boxes are very important in renovation work, because they often avoid the necessity of removing a ceiling (or wall) finish.


Figure 1

Receptacle replacements.Most renovations involve receptacle replacements. In general, receptacles [per 406.3(D)(1)] must have a grounding configuration, and the grounding terminal must actually be connected to the circuit equipment grounding conductor. Figure 1 shows a replacement receptacle on a circuit that has no equipment grounding conductor. In this case, the receptacle could be replaced with a nongrounding configuration, or a grounding configuration could be used if GFCI protection is arranged for the outlet.

In general, receptacle configurations advertise circuit characteristics, and users are entitled [per 406.3(A)] to believe that the configuration is truthful. What about 406.3(D)(b) and (c) where we end up with a grounding configuration without an equipment grounding connection? The NEC balances the enhanced shock protection rendered by the GFCI protective device with the absent grounding connection in such cases through the use of additional marking. A GFCI receptacle, which inherently advertises its function, must be marked "No Equipment Ground” and if the protection is upstream the marking must also include the phrase "GFCI Protected.”


Photo 1. A 6-cu-in., 4-inch-diameter ceiling pan without cable clamps.

The current NEC requires GFCI protection for many receptacle outlets, including those (125-volt, 15- and 20-ampere) in kitchens generally. It also requires [per 406.3(D)(2)] GFCI protection for all receptacle outlets where a receptacle is replaced in a location where the current NEC requires such protection. This is an interesting case from a regulatory standpoint because it may appear to violate the principle that the NEC is not a retroactive document. However, this requirement only applies when an installer performs an action at the outlet, that of replacing a receptacle. No NEC rule requires an existing receptacle to be disturbed, and therefore issues of retroactivity remain with the local jurisdiction.


Photo 2. This is because indoor wet locations frequently involve applications where a "bubble" cover of the sort shown in photo 2 is not rated for upward-directed hose streams, and the only possible solution is a screw-on gasketed cover.

Outdoor receptacles.Renovations do not just involve interior alterations. Frequently receptacles are added for use outdoors. The NEC now requires all 15- and 20-ampere receptacles (125- and 250-volt) located outdoors to have covers that are weatherproof even if the receptacle is in use. This is a major change from the 1999 NEC, which only required such covers if the use would continue on an unattended basis. Note that this requirement does not apply, however, to indoor wet locations. This is because indoor wet locations frequently involve applications where a "bubble” cover of the sort shown in photo 2 is not rated for upward-directed hose streams, and the only possible solution is a screw-on gasketed cover. The NEC, so far, is silent with respect to protecting such receptacles located indoors.

Annular space around box openings.Renovations always involve partition openings, and the author has found that with good communication, 314.21 can be used by the inspection community to make life easier for electricians. These openings must be repaired so there is no gap greater than 1/8 in. at the edge of the box. The dimension comes from the measurement UL uses as the maximum gap that can be left in order to retain the fire-resistance classification of the box (see 300.21). Although many electricians think this makes them plasterers, in fact the problem is frequently poor-quality drywall installation.

If the inspection community makes it known that this rule will be enforced, electrical contractors can offer the general contractors a choice: police their drywall subcontractors, or pay electrician’s rates for drywall repairs. The author has seen the quality of drywall installations improve dramatically in jurisdictions where this has been tried. Remember that when the drywall fits close to the box, the plaster ears on the device will seat securely to the drywall. This avoids the labor required to apply spacers under the yoke in order for it to be "held rigidly at the surface of the wall” [per 406.4(A)].

Boxes in combustible material.Renovations often involve changing wall finishes, such as adding paneling over existing drywall. Boxes must not be recessed in combustible walls (per 314.20), and this means bringing the box forward. If that is not practicable, rings such as the one shown in photo 3 can be used. Although most electricians are aware of this rule, it has a frequently misunderstood companion. NEC 314.25(B) and 410.13 require that when luminaires are installed on combustible surfaces, the surface behind the canopy is to be covered with noncombustible material. This covering need not be metallic; the fiberglass batting often packed in luminaire canopies can serve the function. Be sure the installer has routed the fixture wires behind the fiberglass and out near the center of the canopy. That way they will not rest against the combustible surface, defeating the purpose of the rule.


Photo 3. Renovations often involve changing wall finishes, such as adding paneling over existing drywall. Boxes must not be recessed in combustible walls (per 314.20), and this means bringing the box forward. If that is not practicable, rings such as the

Ceiling-suspended (paddle) fans.Paddle fans are popular and the ones with lighting fixtures attached below them frequently substitute for traditional overhead lights. Safely supporting paddle fans has been a major issue in the industry. Traditional boxes and their product standards have generally assumed a static load held in a particular direction. Paddle fans, especially when rotating fast and with some blade imbalance, impose a load that traditional boxes were not designed to support. In addition to causing box support failures, paddle fan loading overstresses conventional box support methods. In fact, most fan support failures probably have more to do with inadequacies in the way the box was secured to framing than with the integrity of the box itself. Although this is time consuming, inspectors should periodically review fan-box installations for the use of robust support hardware and strict compliance [per 110.3(B)] with the manufacturer’s mounting instructions.

The NEC recognizes boxes specifically listed for the support of paddle fans (see photo 4). They can generally support 35-lb fans, and heavier ones if so listed. They undergo a rigorous testing protocol involving a very heavy fan run for a long period at very high speeds with a severe blade imbalance, and with one of the screws that secure the fan to the box deliberately loosened in some cases. Contractors should discuss this carefully with their customers, because it is much easier to rough in paddle fan support boxes at the likely locations than it is to install them at existing outlets later, especially if there isn’t framing in place that would allow independent fan support at the outlet location.


Photo 4. The NEC recognizes boxes specifically listed for the support of paddle fans

With respect to framing support, the NEC allows paddle fans of any weight to be supported directly from structural elements of the building even at a traditional outlet box, because the building structure and not the box will be the primary support of the fan. This procedure has the additional virtue of allowing a fan to be mounted on any size or configuration of boxes, extension boxes, and plaster rings, some or all of which may not be available in a form listed for direct fan support.2

Connections to concealed knob-and-tube wiring. In cases where the existing wiring is concealed knob-and-tube, the NEC does allow it to be extended from an existing application. But that is seldom practical because the hardware is no longer readily available, and the existing knobs salvaged from old jobs have internal spacings for old Type R conductor insulation that will not work on today’s thinner insulated conductors. Concealed knob-and-tube, as a wiring method, has no equipment grounding conductor carried with it. Over the generations, NEC provisions have changed to the point that it is almost impossible legally to wire anything without grounding it. For example, until the 1984 NEC, what is now 314.4 only required the grounding of metal boxes used with concealed knob-and-tube wiring if in contact with metal lath or metallic surfaces. Now all metal boxes must be grounded without exception.

Meanwhile, grounding has been getting more difficult to arrange to remote extensions of concealed knob-and-tube outlets. Until the 1993 NEC, you could go to a local bonded water pipe to pick up an equipment grounding connection, and then extend from there with modern wiring methods. Now 250.130(C), which governs this work, requires that the equipment grounding connection be made on the equipment grounding terminal bar of the supply panelboard, or directly to the grounding electrode system or grounding electrode conductor. You will not be inspecting grounding connections associated with concealed knob-and-tube wiring in a steel-frame building. Rather you will see this in old wood-frame buildings, probably residential. In such occupancies, even if the water supply lateral is metallic, the water piping system ceases to be considered as an electrode beyond 5 feet from the point of entry. This usually means fishing into the basement. If the contractor can fish a ground wire down to this point, he or she can fish a modern circuit up in the reverse direction and avoid the entire problem.

It is true that some geographical areas have more extensive use of slab-on-grade construction, and here interior water piping is sometimes permitted to qualify as electrodes because the pipes extend to grade for the minimum threshold distance of 10 feet, and thereby allow interior connections. But in almost every case, extensions of concealed knob-and-tube wiring do not do well upon close inspection.

In addition to the grounding issue, beginning with the 1987 NEC this wiring method cannot be used in wall or ceiling cavities that have "loose, filled, or foamed-in-place insulating material that envelops the conductors.” This effectively means that such cavities cannot be insulated, because the only method of compliance involves opening all the walls to install board insulation products, and no contractor is going to keep this wiring method with the walls open. This rule is particularly controversial because, to the extent enforced in existing construction, it is a powerful economic disincentive for owners to retrofit thermal insulation.3

Communication: Making the Process Work

Renovations offer a unique opportunity to bring parts of a building into compliance with current code requirements, increasing safety. However, if the requirements are too onerous, the owner may decide to forego the effort. The inspection community has the delicate responsibility of weighing how to apply the principles at the beginning of this article to the various code issues involved, such as those addressed in the second half of the article.

How well we succeed in making this process work will usually turn on how well we communicate among ourselves and with the owners and other stakeholders. The contractor has to take the time to be clear with the owner as to code issues in the owner’s design preferences. The contractor also needs to build into this discussion an awareness of what issues need to be interpreted by the inspector, and to then provide plans for the inspector on a timely basis. The inspector needs to set aside enough time to review the plans so the contractor and owner are not surprised after they have settled on a contract. If that time is not available, and with today’s economic trends that is too often the case, there should at least be a detailed telephone conversation. In addition, both contractors and inspectors need to be involved with organizations like IAEI, through which collective efforts, such as the Inspection Initiative, can be focused on the political authorities who often make the final decisions based on fees and staffing levels.

1Herbert P. Richter and Frederic P. Hartwell,Practical Electrical Wiring, 18th ed., Park Publishing, Minneapolis, Minn., 2001, p. 394

2Ibid, pp. 356-357

3Ibid, pp. 392-393

The information in this article is excerpted fromPractical Electrical Wiring, 18th edition, and Wiring Simplified, 40th edition. These books may be purchased from IAEI — 800-786-4234.


Read more by Frederic P. Hartwell

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