2: Improper or inadequate maintenance can result in increased fault clearing time of the overcurrent protective device, thus increasing the incident energy. 1: An example of a standard that provides information for arc-resistant switchgear referred to in Table 130.5(C) is IEEE C37.20.7, Guide for Testing Metal-Enclosed Switchgear Rated Up to 38 kV for Internal Arcing Faults. Where this table identifies “Yes” as an estimate of likelihood of occurrence, it means that additional protective measures are required to be selected and implemented according to the hierarchy of risk control identified in NFPA 70E 110.1(H). Where this table identifies “No” as an estimate of likelihood of occurrence, it means that an arc flash incident is not likely to occur. The estimate of the likelihood of occurrence contained in this table does not cover every possible condition or situation, nor does it address severity of injury or damage to health. Risk assessment is an overall process that involves estimating both the likelihood of occurrence and severity to determine if additional protective measures are required. *As defined in this standard, the two components of risk are the likelihood of occurrence of injury or damage to health and the severity of injury or damage to health that results from a hazard. There is no evidence of impending failure such as arcing, overheating, loose or bound equipment parts, visible damage, or deterioration.Equipment covers are in place and secured.Equipment doors are closed and secured.The equipment is used in accordance with instructions included in the listing and labeling and in accordance with manufacturer’s instructions.The equipment is properly maintained in accordance with the manufacturer's recommendations and applicable industry codes and standards.The equipment is properly installed in accordance with the manufacturer’s recommendations and applicable industry codes and standards.PPE is considered the least effective control for employee protection and should not be the first or only hazard control used.Įquipment condition is considered to be “normal” if all of the following circumstances apply: PPE should only be used after all other means of employee protection have been exhausted. If a likelihood exists, other hazard control options must be used first. Rather, it's purpose it to aid in determining the likelihood of an arc flash incident occurring. If any of the criteria are not met, the equipment condition would be considered "Abnormal." This table does not determine if arc flash PPE is necessary. See the note at the end of table that describes what is considered a "Normal" equipment condition. Both AC and DC tasks are listed in the table. The third column says if there is a likelihood of an arc flash incident (“Yes/No”). The second column describes the condition of the equipment, which effects the likelihood of an arc flash incident. NFPA 70E Table 130.5(C) is applicable to both the PPE Categories Method (Tables Method) and the Incident Energy Analysis Method of arc flash risk assessment.
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