Security requires that the room not be shared with other building functions. Considerations for the facility are floor loading factors, water avoidance, ceilings and walls, fire door, lighting, electrical access, room size, electrical grounding, HVAC, floor location, and cable run maximum lengths. Backbone raceways are a series of accesses that connect the entrance wiring closet to the various floor wiring closets. These paths permit cable to be placed between the floors. They may be slots, sleeves, conduits or trays and racks in which cables may be routed for support and protection.
Considerations are the size, quantity, and seals.
If conduits or sleeves are used, the 4 inch size is preferred. The in depth document contains a table giving the number of paths needed, based upon building size. The horizontal raceway carries the cable from the floor wiring closet to the various rooms on the floor. There are many types of systems available today and the pros and cons of each are covered in the detail document. Ceiling trays used in conjunction with utility columns and conduit paths are the preferred method of horizontal distribution.