Recently I completed an arc flash engineering study (a.k.a. an arc flash risk assessment) and then labeled the electrical equipment. I was asked by the electrical engineer at the plant as to whether the arc flash engineering study was based on NFPA 70E® – 2015 Standard for Electrical Safety in the Workplace or the recently published NFPA 70E® – 2018. My reply was, “Neither – it is based on the IEEE 1584™ IEEE Guide for Performing Arc-Flash Hazard Calculations.” Unhappy with my response, the engineer pushed for an answer, prompting me to ask him what the point of his question was.
It turned out that the company followed the NFPA 70E® – 2015 arc rated PPE guidelines based on Table 130.7(C)(16) Personal Protective Equipment (PPE). According to the plant engineer, following the requirements of Category 1 did not warrant the use of a balaclava. The engineer was referring to a label on a panel that stated that the Incident Energy was 3.6 cal/cm2 at 18 inches, and it had an arc flash boundary of 35 inches requiring a minimum 4cal/cm2 arc rated clothing rated PPE.
Apparently, the site was divided on the use of the balaclava: one site used a balaclava with a face shield while the other used only a face shield. This site claimed that the NFPA 70E® – 2015 requirement for a balaclava for incident energies between 1.2cal/cm2 and 12 cal/cm2 was in the Annex of the standard (see Annex H – Table H.3(b)) and not a mandatory requirement. The engineer’s original question now made sense.
NFPA 70E® – 2018 states that if an arc flash hazard analysis was performed previously and met the requirements of the revision that was effective at the time, the label need not be upgraded. Some may erroneously interpret this to claim that the PPE matched to the label at that time may still be valid. This is definitely not the case.
The answer resides in both (1) determining the arc flash protection boundary and (2) the type of analysis used (NFPA 70E tables or the engineering analysis).
If the NFPA 70E® -2015 Table 130.7(C)(15)(A)/(B) was used to determine the arc flash energy, then the PPE is determined by NFPA 70E – 2015 130.7(C)(16). Although the table for PPE Category 1 did not require a balaclava, NFPA 70E – 2015 130.7(C)(10)(b)(1) states that if the back of the head is inside the arc flash boundary, then a balaclava shall be used. This mandatory requirement has remained unchanged in NFPA 70E® – 2018.
If, however, an engineering arc flash study was performed using NFPA 70E® – 2015, that standard made reference to Annex H.3(b), which was not a mandatory requirement. That meant that if an engineering arc flash study was performed and the incident arc flash energy was 3.6 cal/cm2, a company could technically allow the use of only a face shield without a balaclava since it was in the Annex of the standard and not a mandatory requirement.
NFPA 70E® – 2015 Article 130.7(C)(3) requires workers to protect their necks from exposure to arc flash. Considering the previous example, a worker would be in the arc flash boundary, meaning the neck (front and back) may be exposed to the arc energy. Acceptable protective equipment would be a balaclava, hood, or a composite face shield incorporating arc rated fabric.
NFPA 70E® – 2018 addresses arc flash risk assessment in Article 130.5 and now provides Table 130.5(G) for determining the appropriate PPE if an arc flash engineering study is performed. Moving this table from Annex H to the body of the standard makes it a mandatory requirement and clarifies this issue. Whether or not a company elects to replace their arc flash labels, the PPE requirements should be based on the latest standard. Face shields shall be used with a balaclava if the incident energy is greater than 1.2cal/cm2 as determined from an arc flash engineering study or other means of an incident energy analysis.
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