BS 7671 (2008 +A3), regulations 522. 4 and 522, require that if conductors are not continuously supported, that they shall be supported at suitable intervals to ensure sure they are not damaged due to their own weight. The spacing stated for horizontal runs may be applied also to runs at an angle of more than 30 Degrees from the vertical. Put simply, the support spacing is the distance between the brackets. Whilst. The spacing between trays, whether horizontal or vertical, depends on various factors like cable type, environment, and tray material. Proper installation can significantly reduce electromagnetic interference, prevent fire hazards, and improve overall efficiency.