1. For indoor installations, the span between supports or hangers is generally 1.5–3 m; for outdoor installations on vertical columns, the span is generally 6 m.
2. The arrangement of supports and hangers for non-linear sections must adhere to the following principles: when the cable tray width is 300 mm, an additional support or hanger must be installed at the midpoint of the non-linear section, in addition to meeting other applicable requirements.
3. When cable trays are arranged in multiple tiers, the center-to-center spacing between tiers shall be 200, 250, 300, or 350 mm.
4. For straight sections of metal cable trays, an expansion joint of 20–30 mm must be provided every 50 m.
5. Sections requiring fire protection must utilize steel or non-combustible/flame-retardant materials.
