Safety is the most important thing here. I use a voltage tester to double-check. I also put up signs so no one accidentally turns it back on. Safety First: We put on our safety hats, gloves, and. The use and installation of cable trays is covered by legally enforceable OSHA regulations in 29 CFR 1910. 305(a)(3), or comparable standards promulgated by States operating OSHA-approved State plans. In addition, this document contains several references to provisions of the National Electric Code. If a tray is overloaded, corroded, poorly supported, or contains live cables, it can create severe risks for workers and equipment. When cables are improperly routed within the tray, they may face undue pressure or friction. Such forces can cause the cable's outer insulation to break, or worse. According to the 2005 National Electrical Code® (NEC), a cable tray system is “ unit or assembly of units or sections and associated fittings forming a structural system used to securely fasten or support cables and raceways.
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