Codes, Standards, and General Requirements Cable tray systems are recognized as a wiring method by many national and international electrical codes. When properly selected and installed, cable trays simplify routing, improve accessibility, and support future expansion while. Recognize electrical cable tray misuse that can lead to electric shock and arc-flash/blast events and fires caused by overheating. 305(a)(3), or comparable standards promulgated by States. The primary rulebook used in the safe use of cable trays is NEC Article 392. This guide covers the critical steps, from selecting the right electrical cable tray and performing accurate cable fill. Cable tray installation must comply with specific technical standards to ensure electrical safety, system reliability, and long-term maintainability.