Category 0 was removed from NFPA 70E year 2015 PPE table because the new PPE table only specifies work within the arc flash boundary. HRC 0 would mean the worker was outside the arc flash boundary and did not need arc-rated PPE or clothing. According to note (14) on page 7, "Hazard/risk category 0 has been removed from Table 130.7(C)(16)… Hazard/risk category 0 was deleted because the new PPE table only specifies work within the arc flash boundary. If there is no arc flash hazard, then no arc flash PPE is required and it is therefore not necessary on a table devoted to PPE."
There are two methods to select the appropriate PPE.
An incident energy analysis shall be required in accordance with 130.5 for the following:
The problem with using the NFPA 70E table method is that you need to know short circuit current and clearing time of the protective device for the equipment you are using the tables for. Without an engineering study, you don't know that. If the arc flash PPE cannot be determined by the tables, an arc flash calculation must be performed.
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