This Article includes all definitions for terms used within NFPA 70E. There are no parts within this article. The terms in Article 100 are in alphabetical order and arranged in a manner to make it easier to find the term the user of the document is seeking.
The definition itself must follow some basic rules identified by the 2020 National Electrical Code Style Manual. Understanding these rules will help with the proper application of the standard.
Requirements:
The definition of the term is not permitted to contain requirements. Words like shall are not permitted to be located within the definition of any term.
Subparts:
Some terms have modifying descriptors that describe the main term which creates multiple terms that must be defined. A good example of this in NFPA 70E is the term “Conductor”. There are different conductors referenced in NFPA 70E including a “bare conductor”, “covered conductor”, and “insulated conductor”. To keep these terms next to each other in Article 100, the structure of the term itself that is to be defined is included after the term. (term, descriptive adjective). For the term conductor, the subpart terms are shown in article 100 as follows:
Conductor, Bare
Conductor, Covered
Conductor, Insulated
This helps keep all defintitions that impact the main term “Conductor” next to each other in the list of terms found in Article 100. This is structed as such for useability, the ease of finding the definition of a term.
Searchability:
The enhance and accommodate electronic searching of the document, terms, which have been arranged with the modifying descriptor after the term, include the term as it appears in the document within parenthesis. As an example, the different conductor terms with descriptor appear as follows:
Conductor, Bare (Bare Conductor)
Conductor, Covered (Covered Conductor)
Conductor, Insulated (Insulated Conductor)
Applicability:
Some terms that are defined apply to a single Article. When this is the case, the Article number will appear in parenthesis at the end of the definition. An example of this can be found in the definition of “Pilot Cell” which has “(320)” at the end of the definition. This means that the term “Pilot Cell” only applies to Article 320 which includes the safety requirements related to batteries and battery rooms. If the term is used elsewhere, this definition is not applicable in other Articles.
Extracted text:
When a definition is extracted without modification from another NFPA document, the reference document number, and related information to help the user find the location in that document, is included within brackets “[ ]” at the end of the definition. NFPA 70E extracts terms and their definitions from such documents as NFPA 70. An example of this can be found in the terms Overcurrent where at the end of this definition is found [70:100]. This indicates that the term was extracted from NFPA 70, Article 100.
Multiple definitions for same term:
In some cases, a single term may be listed twice with an identifier that provides context for the term found. The context for use of the term is found in parenthesis directly after the term itself. The term “Exposed” is an example of this within NFPA 70E. This term is listed twice in the definition as follows:
Exposed (As applied to energized electrical conductors or circuit parts)
Exposed (As applied to wiring methods)
When these terms are used, the content in parenthesis found in Article 100 shown above are not included. The user of the document must understand the context within which the term is used to use the correct term and its associated definition in Article 100.
Some terms include this context included within parenthesis but do not have duplicate terms. The following definition has the descriptor in parenthesis to narrow the context of which this term can be used but does not include multiple terms being listed in Article 100.
Hazard, Arc Blast (Arc Blast hazard) (As applied to capacitors)
Synonyms:
Some terms may have synonyms that are used. In this case, for clarity and to avoid creating the same definition for multiple terms, the synonyms will be found within parenthesis after the term. Some examples of this found in NFPA 70E are as follows:
Research and Development (R&D)
Attachment Plug (Plug Cap) (Plug)
2024 Changes
All definitions are being moved to Article 100. Reference NEC Style manual section 2.2.2 for the requirement that all definitions have to be in Article 100. Most definitions have not changed except for adding the article at the end of the definition and possibly changes to accommodate the NEC Style manual for alphabetizing and searching.
For example, Section 2.2.2.3 of the NEC Style manual requires definitions that have subparts shall be listed alphabetically by the base term, with a comma and then the modifying descriptor. An example given includes:
- Boundary, Arc Flash (Arc Flash Boundary)
- Boundary, Limited Approach (Limited Approach Boundary)
- Boundary, Restricted Approach (Restricted Approach Boundary)
In addition, section 2.2.2.3.1 of the NEC style manual requires a specific format for the defined terms for electronic searching. The defined term has to include in parentheses as it would be found in the document. Some exampmles are as follows:
- Boundary, Arc Flash (Arc Flash Boundary)
- Boundary, Limited Approach (Limited Approach Boundary)
- Boundary, Restricted Approach (Restricted Approach Boundary)
2024 Cycle Notables
Normal Operation
During the second draft meetings, the terms “Normal Operation” and “Normal Operating Condition” received interesting discussion. Some felt that these two terms may be needed in Article 100. There were proposed definitions but they did not reflect accurately how these terms are used in the standard. This is one area where a task group effort will probably occur in the future for next cycle. There is a need to define these terms but it just isnt happening this cycle.
Article Reference
Discussion pertaining to the removal of the article reference at the end of a definition occurred during the second draft meetings. The issue pointed out by some on the committee was that applying that definition as written to the entire document may not apply in the context of each location where the term is used. In some cases, these definitions would have to be modified to make them more general in nature. This is something that impacts other NFPA documents including NFPA 70 and presents a concern but would need a lot of thought. For example, “Safeguarding”, came from chapter 3 and they discussed how to make this apply across the board as safeguarding is a term that probably should apply throughout NFPA 70E. The arguments were made that it is hard to say safeguarding doesn’t apply across the board. The issue with this definition is the reference to “Cell line design” which is specific to where the definition was and not generic for the entire document. The stimulus for this discussion was the relocation of all terms to Article 100 which took a term from a specific article that only applied to that article and placed it in Article 100.
My NFPA 70E 