That Sister Sledge song from the 1970s is about the importance of family relationships. There is a family of electrical standards that support each other among the 250–300 codes and standards covering safety-related topics that NFPA publishes. Each standard has committees that are responsible for the technical content. The NEC has 18 technical committees, known as Code -making panels. The others all have single technical committees responsible for the entire standard. All of the technical committees and Code-making panels report to the National Electrical Code Correlating Committee, which ensures the documents work within their scopes and that their requirements correlate. Every NFPA standard has a title, though they are mostly referred to by number.
The NEC family
The NEC is the leader of a family of electrical standards. It is less often known as NFPA 70 or ANSI/NFPA 70. Some at NFPA like to simply call it 70. I tried to break them of that habit, but it was a struggle. In conversation, 70 sounds an awful like 70E.
The pivotal electrical standards are the NEC, NFPA 70E and NFPA 70B. Like the rest of NFPA standards, they are called primarily by their number rather than their titles. The best known of those standards is NFPA 70E. For the first several editions, 70E had the forgettable title “Electrical Safety Requirements for Employee Workplaces.” It was a tongue twister.
One day, I asked the staff liaison why the committee didn’t choose something simpler, such as “Electrical Safety in the Workplace.” The next thing I knew, they proposed the new title. Yet, it continues to be known simply as 70E. There is no reason to change that thinking because it is so well accepted. During the Occupational Safety and Health Administration’s early days, the agency adopted the 1968 and 1971 National Electrical Codes, as those were the only national electrical safety rules. OSHA’s mandate is workplace safety, and they soon recognized that the NEC contained a lot of installation rules, including many residential installation rules, which went beyond their mandate. The solution was to create NFPA 70E to produce a document that contained only those rules that involved workplace safety. The initial rules were just the installation rules.
OSHA also intended that the rules adopted be somewhat “timeless” so they would not require updating every three years when the NEC was updated. This made it necessary to update NFPA 70E when the NEC was updated.
In addition, OSHA wanted 70E to include safety-related work practices, safety-related maintenance requirements and safety requirements for special equipment. The first few editions had a unique format that was not very user-friendly. The document essentially was four books bound together as one. Each of the document’s parts had its own chapters. After several editions, it was decided to rewrite the document and to adopt the NEC Style Manual.
Although 70E was developed for OSHA, the agency never adopted it. Instead, it adopted regulations that recognize electrical hazards and require training for protection from those hazards. That might not be a bad thing.
One of the big hindrances of the federal system is the Administrative Procedure Act. This is the detailed federal process that must be followed for federal agencies to adopt changes to the Code of Federal Regulations. It can take many years to enact new regulations or to revise existing regulations. Attempts to keep regulations up-to-date with the realities of evolving technologies are difficult.
Fortunately, OSHA’s General Duty Clause requires that each employer “shall furnish to each of his employees employment and a place of employment which are free from recognized hazards that are causing or are likely to cause death or serious physical harm to his employees.” The effect of the General Duty Clause is that consensus standards—such as NFPA 70E—are the documents that recognize the hazards and provide the mitigation. Changes to NFPA 70E are often due to “recognized hazards.”
The General Duty Clause is the perfect solution to an imperfect system of updating federal regulations. Since OSHA didn’t adopt the NFPA 70E and its installation rules were extracted from the NEC , the installation requirements were deleted from 70E, since they are covered in the NEC . This left 70E focused on work practices.
Equipment doesn’t last forever
Another member of the family is NFPA 70B, the “Recommended Practice for Electrical Equipment Maintenance,” simply known as 70B. Because electrical equipment doesn’t last forever, equipment must be maintained at some periodic frequency or it can become unsafe. The NEC simply covers the rules for a safe installation. Therefore, NFPA 70B was created. Workers must exercise safe work practices, including creating an electrically safe work condition, for maintenance to be performed safely (70E).
There is a major effort right now to solidify this relationship among these three important documents by converting NFPA 70B from a recommended practice into a standard, which would change recommendations into requirements. Recommendations are easy to ignore, but requirements mandate actions.
Pyramid of electrical safety
Together, the NEC , 70B and 70E form a pyramid of electrical safety. There has been some discussion about using the NEC Style Manual for 70B. It seems to be a good idea to use a style that has worked so well for the NEC and 70E.
In addition to those pivotal documents, the NEC family includes the following:
- NFPA 73, “Standard for Electrical Inspections for Existing Dwellings”
- NFPA 79, “Electrical Standard for Industrial Machinery”
- NFPA 110, “Standard for Emergency and Standby Power Systems”
- NFPA 111, “Standard on Stored Electrical Energy Emergency and Standby Power Systems”
- NFPA 790, “Standard for Competency of Third-Party Field Evaluation Bodies”
- NFPA 791, “Recommended Practice and Procedures for Unlabeled Electrical Equipment Evaluation”
NFPA 73, “Standard for Electrical Inspections for Existing Dwellings,” was first issued in 1990. It was developed to be an essential tool for real estate-type home inspectors. Some home inspectors would not know what were hazards and what were not. Often, they would retroactively require code updates for things that might have been nice to have, but the code would not have required for an existing home. The U.S. Consumer Product Safety Commission, Bethesda, Md., bought a number of copies to send to state officials to encourage adoption. It is a handy document, but I am unaware of any adoptions.
NFPA 79, the “Electrical Standard for Industrial Machinery” has been around since 1961. However, it had its origins as a tentative interim amendment to the NEC . It later appeared as a 1943 supplement to the 1940 NEC as Article 670. It was eventually decided to establish it as a separate standard. Beginning with the 2002 edition, NFPA 79 was harmonized with IEC 60204-1 “Safety of machinery—Electrical equipment of machines—Part 1: General requirements,” an existing standard of the International Electrotechnical Commission, Geneva. Harmonizing with the international standard was helpful because some industrial machinery built outside of the United States is built to the international standard. If international standards are used as a basis, it is necessary to ensure that U.S. requirements are also met.
NFPA 110, the “Standard for Emergency and Standby Power Systems,” goes beyond the installation requirements in NEC articles 700, 701, 702 and 708. It covers the requirements for performance of emergency and standby power systems. In addition to the sources, it covers transfer equipment, controls, supervisory equipment and all related electrical and mechanical equipment. This includes requirements for fuel systems and environmental considerations. Testing and maintenance are also important parts of the standard.
NFPA 111, the “Standard on Stored Energy Emergency and Standby Power Systems,” supplements the requirements in NFPA 110. Section 1.2 indicates that it covers “power sources, transfer equipment, controls, supervisory equipment, and accessory equipment, including integral accessory equipment.” The primary stored energy systems are batteries. NFPA 111 goes beyond the requirements in articles 480 and 706 in the NEC .
We rely on third-party evaluated equipment (listed equipment) in the United States. In other countries, listed equipment is not common. In Europe, much equipment is self-certified for compliance. This practice is known as supplier’s declaration of conformity. Equipment that is not listed is often discovered during an electrical inspection. When the installation is red-tagged in a major new manufacturing facility, it can become a political situation. Electrical inspection authorities will often accept a field evaluation by a competent body.
Field evaluation is a different process than would normally be used for a listing evaluation. Listing evaluation often involves some destructive testing and surveillance of ongoing production to ensure that the product continues to be made with all of the same components as when it was listed. Many of the laboratories that provide product listings also have field-evaluation services.
However, other entities can provide a field evaluation. NFPA 790, “Standard for Competency of Third-Party Field Evaluation Bodies,” is a unique standard that provides criteria that can be used to assess whether the evaluator has the necessary capabilities.
Once the qualifications of the evaluation body are approved, it is necessary to establish an evaluation procedure. NFPA 791, “Recommended Practice and Procedures for Unlabeled Electrical Equipment Evaluation,” provides such a procedure, including what documentation must be included.
This family of documents includes installation, maintenance, safety, unique equipment, existing homes and unlisted equipment. They are separate documents, because together they would make quite a bulky tome, and they usually aren’t all needed at the same time. They are, however, correlated to complement one another.