- Mission Viejo, CA
- Professional Electrical Engineer
I am not in a place to offer criticism of your engineer’s design. This is the basic reason I have attempted to only cite relevant Code language and applicable Standards. Beyond that, I claim no authority and, if your engineer is satisfied with the design, I will not challenge it.Of course
Of course INs are not mandatory in the code. No question about that. I know the engineer can opt to use NFPA820 or not but I would definitely use that if I were the designer.
500.4 (A) only applies for a location already classified as a hazardous location. Because the room is not a hazardous location according to the engineer, he ignores that section.