Cable trays must remain in open, accessible areas to allow for proper maintenance. Aplus Trunking for Floor is a type of cable management system designed to protect and conceal cables running along the floor. Where cables pass through shafts, walls, slabs, or enter electrical panels or cabinets, openings shall be tightly sealed. Cable trays are commonly used in industrial facilities, commercial offices, and factories where maintenance access is readily available. They are approved for supporting various types of circuits, including service conductors, feeders, branch circuits, communications circuits, control circuits, and. WARNING: Do not use a cable tray as a walkway, ladder or support for people.