Ignoring thickness is one of the most common causes of tray deflection and field failures. This could cost millions of dollars in downtime and cause serious safety problems for a facility and its personnel. Our Cable Tray Design Considerations Guide. us-trations without notice. All illustrations, descriptions and technical information included in this document are provided as indications and can cable trays are equivalent. The mechanical and electrical characteristics, tests, certifications, overall quality management, recommendations mentioned. 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. It applies to cable trays made of steel, stainless steel, aluminum, or other metallic materials.