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The Top 10 Changes in the 2002 National Electrical Code

Hundreds of changes, big and small, have been made for the 2002 NEC. Can there be 10 that are the most important? First we would have to decide what makes a change important. A change that is important to one person will not necessarily be important to someone else. Also, different people will judge the changes based on different criteria. For some, important changes are those that change what they

Hundreds of changes, big and small, have been made for the 2002 NEC.

Can there be 10 that are the most important? First we would have to decide what makes a change important. A change that is important to one person will not necessarily be important to someone else. Also, different people will judge the changes based on different criteria.

For some, important changes are those that change what they already know, such as a frequently used article or rule that has been relocated, or a general rule that has been modified. Other people may be primarily interested in what changes will cost money, such as rule that forces them to buy more GFCI receptacles or more AFCI circuit breakers. Another point of interest is a rule that changes the type of equipment or material that will be used, such as changes in requirements for circuit breakers, or a rule that now requires some item to be listed. Any rule that changes established practice will be important to somebody too, such as a rule that changes the way a wiring method can be used or supported.

Of course all of the changes can cost a contractor money if they don't know about the new method that could save some labor or material, or if they have to redo some part of an installation because they didn't learn about a change until it was brought up on inspection.

This article will not identify the 10 most important individual changes. Rather, this article will identify 10 groups or types of changes that are likely to have an effect on electrical designers, installers and inspectors. The new Code books are scheduled to become available in September 2001. Over the next few months, a series of articles in CEE News will summarize many of the individual changes, section by section. This article provides an overview of some of the issues that will face a user of the new NEC.

None of the changes are taken lightly by the 20 Code Making Panels (CMPs) or the Technical Correlating Committee (TCC) that oversees their work. Certainly some changes will have more effect than others, but all of the changes have been supported by a formal proposal, substantiated in some manner, scrutinized by the CMP and the TCC and opened up to public comments. All of the public comments and any new evidence have been similarly considered. The NFPA membership has had a chance to vote on the panel actions, and perhaps amend a few. Finally, the NFPA Standards Council has reviewed the process and any appeals, and submitted the final document to ANSI for adoption as an American National Standard.

The changes vary from minor corrections in grammar or punctuation to new articles on new technologies that have not been addressed in the past. Sometimes the addition of a comma or a semicolon makes a significant difference in the ways a rule can be read, so occasionally a small change has a big impact. On the other hand, once in awhile, a change is accepted in the Code that essentially legitimizes a common practice, and the big new thing in the Code is nothing new at all to the people who thought that particular practice was OK all along.

We are going to look at 10 groups of changes. Each group or type may be represented by many examples, and we will not go into every example in detail. As noted, this will be just a preview of how the Code will look the next time around.

Format and Editorial Changes

A number of changes will make Code references look different throughout the book. Probably most obvious will be that the old “dash” format will be replaced with a “dot” format. This will change spoken references most of all. A section from the 1999 NEC such as “three ten dash fifteen” (310-15) will become “three ten dot fifteen” (310.15). Some people might want to call it a period, like punctuation, or a point like a decimal point. For this author, it's a dot.

Other changes in editorial format will change the way parts, subsections, and lists are referenced. For example, Section 310-15(b)(2)(a) will now be 310.15(B)(2)(a). This is meant to bring the text into a more logical and traditional outline form.

Parts have also been renamed to reflect the outline-type organization of the NEC. Consider Section 820-52(a)(1)(a). In the 1999 NEC this section was in Part E of Article 820, which is in Chapter 8. It will still be in Chapter 8, Article 820, but the part of the article will be Part V (Roman numeral 5) and the rest of the section will be 820.52(A)(1)(a).

With this scheme, the top level of the outline in an article is the part, so the highest level is a Roman numeral, the next level is the section number (in our example, 820.52). The next levels are designated by an upper case letter (A), a decimal integer (1) and a lower case letter (a).

Section 820.52(A)(1)(a) includes a list. Under the new format, a list is always numbered, and can appear under any level of the outline, so 820.52(A)(1)(a)(1) is an item in a list, and so is 547.5(G)(1).

The Code book also differentiates between higher and lower levels by setting the higher levels in bold face type.

Two other style issues include the treatment of metric equivalents and the naming of the supplementary information in the back of the book.

The supplements to the Code will be renamed “Annexes” from “Appendices.” Annex A replaces Appendix A. Other appendixes are just renamed. Annex A will become a list of product standards, mostly UL Standards, with some ISA and IEEE standards included. The old contents of Appendix A, a list of references for extracted text, will now be found in bracketed notes where the extracted text appears in the Code.

Metric “equivalents” will appear first, with English foot-pound sizes in parentheses. For example, in the definition of “In sight from” in Article 100, the specified distance used to be “50 ft (15.24 m)” and now it is “15m (50 ft).” Two methods of conversion are used: “hard” and “soft.” The example given was a hard conversion. The two distances in the example, 15 m and 50 ft, are deemed to be equal from the standpoint of the rules to which they apply.

Soft conversion would have reduced the distance of 50 ft to the exact equivalent of 15 m, or about 49 ft 2-½ in. As in this example, a hard conversion may change the actual dimension somewhat, whereas a soft conversion only changes the description of the dimension, with no change in actual dimensions.

Hard conversions are used when measurements are approximations in practice, such as burial depths. Hard conversions are generally preferred, unless precise dimensions need to be preserved.

Even soft conversions are only precise to the number of significant digits. One type of soft conversion is used with trade sizes because the trade size is not an actual measure.

Rather than change trade sizes to millimeters, trade sizes are given metric designators. For example, the metric trade designators for ½-, ¾-, and 1 in. trade sizes are 16, 21, and 27 respectively, which roughly correspond to metric measurements. In some cases, there are no conversions, such as a reference to a No. 6 screw, where a hard conversion would call out a metric screw that is not interchangeable, and a soft conversion would be meaningless.

New Terms and Acronyms

A new term throughout the Code is “luminaire.” Of course it's not a new term in the industry, but the more commonly known and used term has been “lighting fixture” or just “fixture.” Luminaire is a more encompassing term than fixture. A luminaire includes lamps and all the parts used to position and protect the lamp(s), direct, diffuse or otherwise distribute the light, enclose the ballast where there is one, and connect the lamps to a source of electricity. Where luminaire appears in the NEC will appear as “luminaire (fixture)” at least for this Code cycle.

More acronyms are appearing in the 2002 NEC, especially in Chapter 3. Many people are familiar with the acronym “EMT” for Electrical Metallic Tubing, but most of the raceway types are getting new acronyms in the Code as well. The new names include Type RMC for Rigid Metal Conduit, Type FMC for Flexible Metal Conduit and LFNC for Liquidtight Flexible Nonmetallic Conduit. It may be a while before these new names catch on as trade jargon, but in an industry where the names of things sometimes take eight words and two hyphens, the acronyms can be quite helpful (See the table on page 14).

Articles Moved, Renumbered or Extracted from Existing Articles

Most of the articles in Chapter 3 have been renumbered. The cable articles will now be Articles 320 through 340 using only even numbers to leave room for future additions. Raceway articles will be similarly numbered 342 through 362. Cabinets and Cutout Boxes have moved to Article 312 and Boxes will be covered by Article 314.

The rest of the wiring method articles, such as Busways, Article 368, follow the raceway articles. The articles that dealt with two products, such as Wireways, are now two articles, Nonmetallic Wireways, Article 378, and Metal Wireways, Article 376.

Three articles were moved from Chapter 3 to Chapter 4. The old Article 380 on Switches becomes Article 404. The old Article 384, Switchboards and Panelboards, is now Article 408. These two moves are in keeping with the titles of the chapters. Chapter 3 is Wiring Methods, and Chapter 4 is Equipment for General Use. Since Article 305, Temporary Wiring, was not really about wiring methods either, it was moved to Chapter 5, Article 527, although some disagree about whether temporary wiring is a Special Occupancy.

Two other articles were also created from existing articles. Article 406, which covers Receptacles and Cord Connectors used to be part of Article 410, which is now Luminaires, Lampholders and Lamps. Article 647, Sensitive Electronic Equipment, used to be mostly contained in Article 640, Audio Equipment.

New Articles Covering New Material

The 2002 NEC has three all new articles that cover material not previously included in the Code. Article 80 provides a set of optional administrative rules to assist jurisdictions in adopting and enforcing the NEC. Article 285 covers Transient Voltage Surge Suppressors, which are not the same as the Surge Arrestors covered in Article 380. Article 692 covers the installation and wiring aspects of the emerging fuel cell technology.

New Safety Requirements for People Servicing Equipment

At least four new changes will affect the way equipment is installed and serviced.

The first is in the definition of a “Qualified Person,” which now includes a requirement for safety training.

Second, switchboards, panelboards and industrial control panels will have to be marked with a flash hazard warning. The marking does not apply to dwelling units, and trained people will know how to react to the warnings.

Third, areas with large equipment — more than 1,200A and more than 6-ft wide — must have panic hardware or the equivalent on the exit doors from the equipment spaces, and the doors have to open in the direction of travel.

Fourth, motors will have to have disconnects in sight of the motor. A lockable disconnect at the controller is no longer acceptable as the motor disconnect unless it is also in sight from the motor; in a location where installing a local disconnect might be “impracticable;” or increase hazards (such as in a hazardous location); or in a location where there is a written safety procedure, and only qualified (trained) persons will service the motor.

Revisions to Installation Requirements for Power-Limited Circuits

A series of changes in the articles that cover limited energy circuits now specifically require limited energy cables to be supported from the structure. Spacings between supports are not specified, but all such cables are now prohibited from being laid on a grid ceiling. Accessible cables such as those installed in air-handling ceilings cannot be abandoned in place. Abandoned cables must be removed where they are accessible. Cables in conduits are not considered to be accessible.

These changes affect Audio, Class 1, Class 2, Fire Alarm, fiber-optic communications, CATV and network-powered broadband communications circuits. Abandoned cables must also be removed from computer room raised floors.

Use of Gray and White Conductors

Many installers, designers and inspectors have considered white and gray to be two different colors for grounded conductors.

In fact, the color codes of yellow, orange, brown and gray for 480/277V systems and black, blue, red and white for 208/120V systems are so widely used that many people think the color codes are in the NEC somewhere. Not only are the color codes not in the NEC, but up until 2002, white and gray have not been recognized by the Code as two colors different enough to be used to distinguish between the grounded conductors of two different systems.

Now the color “natural gray,” basically just some version of white, is gone from the Code language. “Gray” becomes another color besides white that can be used for identifying grounded conductors and that can't be used for anything else. In the past, some people have legitimately used gray as a “hot” conductor, where they distinguished between gray and natural gray.

Clarification of Grounding Requirements

Three changes have to do with grounding and piping systems. In 1999, the NEC changed to require a designer or installer of a separately derived system to consider only the first 5 ft of the incoming water line as an electrode. This presented a new problem in some installations, especially high-rise construction where there is no structural steel frame, because each system might have to have a grounding electrode conductor extending to the basement. Now a single riser conductor can be run up through a building for grounding of multiple separately derived systems.

Also, the outside part of a waterline that is attached to the exterior of a building has to be bonded, and the bonding of gas pipe reverts to the 1996 Code language that treated gas pipe as “other metal piping.” As “other metal piping,” the equipment grounding conductor that connects to electrical equipment that could energize the gas piping can also be used as a bonding means for the gas piping.

Changes in the Use of Overcurrent and Wiring Devices

Some new rules concern overcurrent devices. Circuit breakers used for switching high-intensity discharge lighting will have to be marked “HID.” HID is a step up from the familiar SWD marking, so either the SWD marking or the HID marking is now permitted on fluorescent lighting circuits.

The requirement for multi-pole breakers when receptacles are supplied by more than one circuit (more than one breaker) has been extended to all occupancies.

The requirement is for a “means to simultaneously disconnect” the circuits, so handle ties might be permitted by some AHJs. A similar rule has applied to dwelling units for many years.

AFCI circuit breakers will have to protect all the bedroom outlets, including lighting outlets, not just the receptacle outlets.

As for wiring devices, dimmers are not allowed on receptacle circuits, as they are usually intended only for permanently installed fixtures (luminaires). Also, some types of energy management switches (occupancy sensors) may have to be modified.

Some types have supplied a small current through the lamp for the operation of the device. This was useful for replacing a device in a two-wire switch loop. Now, if the device has a marked off position, it must completely disconnect the ungrounded to the load. However, such switches can have “off” positions that turn the light off without being marked off.

Everyday Issues

A few little rules will change how some things are done: 1. Communications circuits in buildings are definitely within the scope of the Code and the enforcement authority of the AHJ. 2. Any permission from an AHJ allowing deviations from Code rules under the provisions of Section 90.4 has to be in writing, just like “special permission.” 3. A common design specification has become a Code rule requiring field-cut threads to be recoated with an approved electrically conductive, corrosion-resistant compound wherever corrosion-protection is necessary, such as most underground conduits.

This article has covered some changes that will affect any Code user, but the Code has other important changes. Look for a more complete summary of the changes starting next month.


Article Name Acronym
342 Intermediate Metal Conduit IMC
344 Rigid Metal Conduit RMC
348 Flexible Metal Conduit FMC
350 Liquidtight Flexible Metal Conduit LFMC
352 Rigid Nonmetallic Conduit RNC
354 Nonmetallic Underground Conduit with Conductors NUCC
356 Liquidtight Flexible Nonmetallic Conduit LFNC
358 Electrical Metallic Tubing EMT
360 Flexible Metallic Tubing FMT
362 Electrical Nonmetallic Tubing ENT


Noel Williams has worked in electrical construction for 25 years. Licensed as an electrical inspector in Utah and licensed as a master electrician in Utah, Wyoming and Colorado, he's co-author of the NFPA's 1999 NEC Changes.

Dann Strube is a nationally recognized NE Code expert and electrical Code consultant. He's a certified electrical inspector in Indiana.

Gregory P. Bierals is president of the Electrical Design Institute. He presents seminars nationwide on various NEC subjects.



Mike Harrington,
Managing Editor, CEE News

Primedia Business Magazines & Media
9800 Metcalf Ave.,
Overland Park, KS 66212

E-mail: [email protected] Include a sketch where appropriate.

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