NEC Article 645 and NFPA 75

[maghazadeh]

Hi everyone, I like to know if there is any exceptions to requirements NEC-645 which permits a IT room not to be fire resistant-rated walls, no need for EPO's as per 645-10, and that we donot have to install fire/smoke dampers.
Thanks in advace for the input.

 

[iwire]

All of Article is 645 is voluntary unless you want to take advantage of the leniences it allows in wiring methods.

 

[ron]

Well said by Bob.
645.4 indicates that the article only applies if you provide EPO's, fire rating, etc.
NFPA 75 is a standard and not a code adopted by any jurisdiction that I am aware of.