Using the NFPA 70E Tables

For determining minimum requirements when using the PPE Categories Method, the NFPA has provided arc flash PPE classifications tables for equipment using AC and DC systems as determined by the level of arc flash hazard exposure. If the task is not listed, it is necessary to use the incident energy analysis method to determine the proper levels of PPE.

 

The NFPA 70E 2015 Article 130.7(C)(15)(A) Alternating Current (ac) Equipment, states that if used instead of the incident energy analysis method as defined in 130.5(B)(1), determining whether arc flash PPE is required can be done by looking up the task given in Table 130.7(C)(15)(A)(a) as shown in the example in Figure 1. If it determined that arc flash PPE is required for the task, then the appropriate PPE category can be found in Table 130.7(C)(15)(A)(b). These categories are derived from the estimated maximum available short-circuit current, the maximum fault-clearing times, and the minimum working distances for various ac equipment types or classifications.

However, an incident energy analysis is required (as specified in NFPA 70E 2015 Article 130.5) if any of the following apply:

  • The task is not listed in Table 130.7(C)(15)(A)(a)
  • For power systems that have more than the estimated maximum available short-circuit current.
  • For power systems that have longer than the maximum fault clearing times.
  • The task has less than the minimum working distance specified.

 

In the NFPA 70E 2015 Article 110.1 Safety programs, the principles are defined to promote an awareness of workplace safety and the potential of electrical hazards. The condition of the equipment is an important part of the total electrical safety program (ESP) developed by the employer which includes policy making, proper training, monitoring and maintenance practices. As such, the equipment condition is a deciding factor in whether arc flash PPE is required for the listed tasks.

 

NFPA 70E 2015 Article 110.1(B) Electrical Safety Program. Maintenance. The electrical safety program shall include elements that consider condition of maintenance of electrical equipment and systems.

 

PPE Categories Tables

If the criteria is met as described above, then the following tables may be utilized to determine the minimum levels of PPE required.

 

NFPA 70E 2015 Table 130.7(C)(15)(A)(b) Arc Flash Hazard PPE Categories for Alternating Current (ac) Systems

(See Figure 2)

 

NFPA 70E 2015 Table 130.7(C)(15)(B) Arc Flash Hazard PPE Categories for DC Current (dc) Systems

(See Figure 3)

 

Reproduced with permission from NFPA70E®-2015, Electrical Safety in the Workplace, Copyright© 2014, National Fire Protection Association. This reprinted material is not the complete and official position of the NFPA on the referenced subject, which is represented only by the standard in its entirety.

 

 Table 130.7(C)(15)(A)(a) Arc Flash Hazard Identification for Alternating Current (ac) and Direct Current (dc) Systems.png

Figure 1: Table 130.7(C)(15)(A)(a) Arc Flash Hazard Identification for Alternating Current (ac) and Direct Current (dc) Systems

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Table 130.7(C)(15)(A)(b) Arc-Flash Hazard PPE Categories for Alternating Current (ac) Systems.png

Figure 2: Table 130.7(C)(15)(A)(b) Arc-Flash Hazard PPE Categories for Alternating Current (ac) Systems

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Table 130.7(C)(15)(B) Arc-Flash Hazard PPE Categories for Direct Current (dc) Systems.png

Figure 3: Table 130.7(C)(15)(B) Arc-Flash Hazard PPE Categories for Direct Current (dc) Systems

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