Use an open style,
The rack should use the universal mounting rail hole pattern identified in IEC Standard 297.
The rack should be made of steel.
The rack should support approximately 272 kilograms (600 pounds).
The rack should have adequate electrical grounding. A distribution rack grounding kit may be used.
The rack should be attached to the wiring closet floor with 9.5 millimeters (3/8 inch) lag screws or equivalent hardware. The floor under the rack should be level within 5 millimeters (3/16 inch). Use a floor leveling cement compound if necessary or bolt the racks to the floor.
Brace open racks if the channel thickness is less than 6.4 millimeters
(1/4 inch).
Install equipment in the lower half of the equipment rack to avoid making the rack top too heavy.
