To effectively apply NFPA 70E requirements, all users must have a comprehensive understanding of the definitions in the standard that will affect electrical safe work practices in their workplace.

Chapter 1 of NFPA 70E contains Article 100, Definitions. The scope of this article clarifies that only definitions essential to proper application of NFPA 70E are included. It does not contain general or commonly defined/understood terms that may exist in another code or standard. Where there is an article number in parentheses at the end of the definition, that defined term applies only within the article referenced. Where there are brackets at the end of a definition, the term is extracted from another NFPA code or standard. 

For example, the defined term “device” is followed by [70:100], meaning that it is extracted from NFPA 70, the National Electrical Code, in Article 100. There are 136 definitions in Article 100. There are 51 definitions extracted from the NEC. There are 33 definitions that apply only to articles in Chapter 3, which address safety requirements for special equipment. This article will focus on several of the most basic defined terms the user must understand. 

Qualified person

The general definition of qualified person comes first. To be qualified, one must demonstrate skills and knowledge related to the construction and operation of electrical equipment and installations they will interact with. It is imperative for all electrical workers to recognize equipment and installations they are not familiar with and seek additional training. 

Frontline foremen must ensure qualified status. There are many types of installations including, but not limited to, systems that are single-phase 3-wire, three-phase wye-connected, three-phase 4-wire delta, three-phase delta ungrounded and corner-grounded systems. Qualified people must also have safety training to identify the hazards and reduce the associated risk. 

Also, the training requirements in Section 110.4 are necessary for all electrical workers. A common misconception is that 70E exists to train electrical workers on requirements for working energized. The goal of 70E is to eliminate the hazard and create an electrically safe work condition (ESWC). 

ESWC and related terms

The defined term ESWC clarifies it is a state in which equipment (conductors or circuit parts) has been disconnected from energized parts, locked/tagged in accordance with established standards (the employer’s prescriptive steps for LOTO), tested for the absence of voltage and, if necessary, temporarily grounded for personnel protection. Properly establishing an ESWC places equipment in a state that eliminates electrical hazards for the period work is performed. 

Part of the training requirement in 110.4(A)(1) mandates that qualified people be trained to identify and avoid electrical hazards, which is imperative. An electric shock hazard is defined as a source of possible injury or damage to health associated with current through the body. Many electrical workers immediately understand, as they have been shocked in the past. 

The definition of arc flash hazard (source of possible injury or damage to health from energy caused by an electric arc) is technically correct, but does not provide clarity as to where or when an arc flash hazard exists. 

The associated informational notes provide the user with the necessary information to determine when or where an arc flash hazard exists. The likelihood of an arc flash incident increases when energized electrical conductors or circuit parts are exposed or within equipment in a guarded or enclosed condition, provided a person is interacting with the equipment in such a manner that could cause an electric arc. 

A second informational note sends the user to Table 130.5(C) for examples of tasks that increase the likelihood of an arc flash incident occurring. In Table 130.5(C), the defined term “working on” is used multiple times and means intentionally coming in contact with energized electrical conductors or circuit parts. This includes intended contact with the hands, tools, probes or test equipment. Voltage testing during troubleshooting and testing for the absence of voltage as part of an ESWC are examples of this. 

Risk assessment

In my opinion, the definition of risk assessment is one that all electrical workers should be able to recite just as they would the Pledge of Allegiance. This defined term applies to all employees, in all industries. It is not limited to electrical hazards. A risk assessment is a process, not a single step. First, identify a hazard. Second, estimate the likelihood of occurrence of injury or damage to health from the identified hazard, based on the task. Third, estimate the potential severity of injury or damage to health, which could range from a cut requiring stitches to a fatality. Finally, determine if protective measures are required, which sends the user to the hierarchy of risk control methods.

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