Arc Flash Risk Assessments

[Shawn L]

In the older versions of NFPA 70E there was an exception for performing an arc flash risk assessment (formerly known as an arc flash hazard analysis). The exceptions included:
1. The circuit is rated at 240 Volts or less
2. The circuit is supplied by one transformer
3. The transformer supplying the circuit is rated less than 125 kVA.
In the 2015 version in section 130.5 is states that an arc flash risk assessment shall be performed.
Do the same exceptions still apply? If so, can you provide where these exceptions are stated in the 2015 version.
Thanks in advance.

 

[ron]

That exception was found in IEEE 1584. I'm not sure it was in 70E.

 

[petersonra]

As a practical matter it appears to me that the IEEE had made the assessment regarding the level of risk under the specified conditions.

I am not real sure what triggered the idea that this was no longer a valid assessment. maybe PEs feeling like their business was being poached. Or maybe new data that suggests the situation was not as clear cut as first thought.

 

[jim dungar]

NFPA70E felt this type of issue only involved the specific calculation methodology chosen and therefore this specific exception was removed from the '70E standard'.

The mentioned 'exception' can be found in IEEE 1584.