Cable Types: Only use conductors rated for open-air environments, such as Tray Rated (Type TC) or Metal-Clad (Type MC) cables. Clearances: Maintain at least 12 inches of vertical clearance above trays for installation and maintenance access (2026 NEC update). The use and installation of cable trays is covered by legally enforceable OSHA regulations in 29 CFR 1910. The mechanical and electrical characteristics, tests. in this document have been tested extens ompetent professional en completely installed, without damage either to conductors or structural system use maintain spacing or to keep cables in place when the tray is ect the minimum bend ra-dius for cables as they exit the bottom of the cable tray. A. us-trations without notice. Copyright © 2008 by the Institute of Electrical and Electronics Engineers, Inc. If you have any questions about IEC copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or your local IEC member National Committee for further information. Droits de reproduction réservés.