Secure the Rack
The rack should be attached to the wiring closet floor with 9.5 mm (3/8 in) lag screws or equivalent hardware. The floor under the rack should be level within 5 mm (3/16 in). Use a floor-leveling cement compound if necessary or bolt the racks to the floor as shown.
Properly Secured Rack

Brace open equipment racks if the channel thickness is less than 6.4 mm (1/4 in).