Conflict between NFPA 75 and NFPA 70 question
I am evaluating a data center emergency power off (EPO) system that a client designed and have been told there is a descrepancy between NFPA 70 and NFPA 75 but I cannot find an issue between these two codes.
Does anyone know of such a descrepancy?
The design has EPO pushbuttons to shutdown the power to electronic equipment, the HVAC, the UPss and he even went one step further and has a kill the whole building mounted outside the building in case the first responders need to kill the building.
I am not aware of a difference between the standard (NFPA 75) and the Code (NFPA 70).
The Standard is not enforceable in most (if not all) states, but the code is. So follow NFPA 70 for minimum requirements.
It sounds like it might meet minimum code requirements but would be a reliability nightmare.
I assume exit and emergency lighting remains connected to an emergency source throughout the rest of the building. Otherwise, that would be an issue.
75 versus 70
I am an NFPA member and I will tell you to follow the 70 code. 75 is for the Standard for the Protection of Information Technology Equipment. It is just a standard. The NEC is referenced by OSHA as wel as all communities within the US. The bottom line is you can replace IT equipment but you cannot replace a life.
Not sure what Steve66 is speaking about but emergency lighting and exit signs are battery backed up. The first thing that the Fire Department will do is pull your main switches in the substation outside. They will make the call since this will shut down the sprinkler system as well but it is there call. We just need to make shure the dissconnecting means are their as it is called out in the NEC.
70 and 75 are both NFPA documents. The key is that 70 is a code and typically 75 is not adopted as a code in most jurisdictions.
I am a big proponent of following the regular portions of the code and not using the leniencies provided by 645 in the NEC, so in many of my datacenters ... no EPO's.
75 vs 70
I'm not sure what you are saying with "I am a big proponent of following the regular portions of the code and not using the leniencies provided by 645 in the NEC, so in many of my datacenters ... no EPO's."
What regular portions in NFPA 70 take exceptions to the leniencies provided by 645 are you referring to?
In many of your data centers, in the event of a meltdown, how are you turning off power to the electronic equipment and HVAC computer room units, shutting smoke/fire dampers, etc. after activation of the FM200 releasing system via dual smoke (cross zoned) smoke detectors signalling an alarm?
645 is an optional article in the NEC.
In 645.4 it says that the article applies only if you comply with the portions of 645.4. If you don't put in an EPO from 645.4 (and 645.10), then 645 does not apply and you would install stuff in the data center like any other commerical building, such as plenum rated cable in a plenum, securing raceway, etc.
NFPA 70, article 645 is optional?
I may need to go back to basics; but how has it been determined that 645 is an optional article in the NEC? In my copy of the NEC, I see no references to 'regular' sections and 'optional' sections and I don't think that Code-Making Panel No. 12 would be pleased to learn their articles, including 645, are optional.
NEC chapters 1 thru 4 apply generally, chapters 5, 6 & 7 apply to special occupancies, etc. Per NEC 90.3; chapters 5, 6 & 7 supplement or modifies requirements of chapters 1 thru 4.
Though slightly out of context, I notice in 645.1 that there's a FPN saying for further information, see NFPA 75 - 2003.
It is the text of 645.4 that makes it optional.
"This article shall apply, provided all of the following conditions are met: ...."
If you don't comply with any one of 645.4(1) -(5), the the article doesn't apply.
I don't put in an EPO from 645.4(1) .... then the article doesn't apply.
There are several mag articles published regarding the optional nature of 645, but I will need to get back as I'm running out now.