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In accordance with NFPA 70E® Section 110.3(F), an electrical safety program should include a hazard identification and risk assessment procedure. This procedure is to be used before work is started within the limited approach boundary or within the arc flash boundary under certain conditions. The conditions are that there are energized electrical conductors and circuit parts operating at 50 volts or more, or that an electrical hazard exists. From the pertinent definition of exposed and of limited approach boundary in Article 100, there is no limited approach boundary if the energized conductors or circuit parts operating at 50 volts or more are suitably guarded, isolated or insulated. The determination of the arc flash boundary is independent of the determination of the shock hazard boundaries. Finally, the electrical safety plan is to identify the process by which an employee can identify hazards and assess risks before work is started, including potential risk mitigation strategies.

Informative Annex F of NFPA 70E makes clear the importance of understanding and developing a systematic or orderly approach to hazard identification, risk estimation, and the application of the available methods of hazard control so as to reduce the risk associated with a particular hazard/task pair to an acceptable level. Froman electrical safety standpoint, risk can be defined as the likelihood of the occurrence of a hazardous event, and the severity of the injury that might be caused by the event. Once the level of risk is determined, if that level of risk is not acceptable, safety controls (protective measures) have to be put in place to reduce the risk to a suitable level. Therefore, it is extremely important to understand the safety control measures that are available for risk reduction, and to have a systematic approach of applying these safety control measures to the risk reduction task.

In many organizations, the responsibility for seeing that hazard identification and risk assessment is properly performed for electrical safety issues belongs to the electrical safety committee, which may be a subcommittee of the general environmental health and safety committee. Hazard identification and risk assessment is effectively dependent on the members of the committee or their designees that are assigned to perform these important tasks, and the procedure is limited by the assigned personnel’s experience or knowledge of electrical safety failures.

In Section F.2 of Informative Annex F, NFPA 70E defines risk as the severity of harm or possible harm associated with a hazard/task pair and the probability of occurrence of that harm. The probability of occurrence is a function of the frequency and duration of the exposure of persons to that harm, the probability of occurrence of the hazardous event, and the possibility of avoiding or limiting the harm associated with the hazardous event. Risk, or the risk priority number (RPN), may be described by the following equation:

Ground-fault circuit-interrupter (GFCI) protection has been in the National Electrical Code® (NEC®) for 50 years.  Many thought there could not possibly be any additional locations where GFCI protection was needed, but the 2011 edition shows that there are still areas that can benefit from this protection. Actually, new GFCI requirements have been added in every edition since 1971, but most people are only aware of those specified in 210.8. This article looks back at the history of GFCI requirements.  Although Articles 210, 590 and 680 — those that have the longest history — are the focus, other notable requirements are included. Also, Code terminology has changed over the years; the terms used will be from the edition referenced. 

After the risk has been assessed and evaluated and appropriate electrical safety controls (protective measures) have been determined and put in place, the final step before electrical work is actually started is to ensure that all required electrical safety controls have been implemented. This is accomplished through a verification process. Verification is the act of confirming the truth of a matter or situation through evidence. We might call it a verification and validation process, because what we’re discussing is a process of checking that a product, service, system, or the like meets specifications and fulfills its intended purpose. Here, it is the act of confirming that the required electrical safety controls (protective measures) have been put into place and are ready to be used. This requirement is discussed in F.5.1 of Informative Annex F of NFPA 70E.