COOLing how to choose the better system for my Data Centre?

As I am a S.XX engineer I learnt that a DC must be at 15oC-18oC and with RH%  and have a crystal doors and raised flooring and whips to the main frame and.....and.... But today I have had to LEARN to RE Learn and forget those paradigms that I use to see in a old good days Data centre.

But today the IT equipment can works at 30oC with 40 to 80% RH and so on. of course those equipment must be the same kind, quality and be good enough to set the OPEration point in such limits. I understand that not all equipment in a DC is alike; that a COLO/HOST; CLOUD , Enterprise, Military and so on facilities are DIFFERENT. I really understand that.

And of course I also understand that exist a variety of new alternatives to set a DC (modular, container, pods, cabinets(all in one);  those technical offerings that vendors have put in the market up to date.

But can you figure out how ANY project MUST  choose among all of them?

• Owners´Project Requierements?
• Base of Design?
• COLO/HOST; CLOUD, Eneterprise, ...... type 
• Longitude, Latitude, Altitude facility´s coordinates?
• Sustainability requirements?
• Energy Efficiency requirements?  PUE, WUE, CUE,....
• Availability requirements (99.99999999.......)
• Standards Compliance (TIA, NMX, EUCoC, EN, TGG..., SOX, BASILEA III,....
• RISK management
• Classification requirements (TIA, NMX, CEEDA, UTI, LEED,.....)
• Vendors´ choice?
• Business as usual?
• IT´s equipment Thermal load?
• Quarter & Quota commitment?
• any other...?

As we can see all of them are IMPORTANT, all of them can be claim as necessary or vital or.......

We as designer must understand the special needs of  "THE" facility before the choice is made. or what we have to do?; can you discuss your method to choice; this will enligth our knowledge.

or what do you think?

roberto sanchez, RCDD

México