Maintain at least 25 mm horizontal clearance between cable trays and water pipes, with larger distances for hot or corrosive pipes.

Recommended Horizontal Clearances

• Standard water pipes: A minimum horizontal spacing of 25 mm from cable trays is recommended to allow safe installation and maintenance access, as per AS/NZS 3000 standards .
• Hot pipes (thermal pipes): If the pipes carry hot water or steam, the horizontal distance should be increased to 0.5–1 meter, depending on whether insulation is present, to prevent heat damage to cables .
• Corrosive or chemical pipes: For pipes carrying corrosive liquids or gases, maintain at least 0.5 meters and consider protective coatings or corrosion-resistant cable trays .

Practical Considerations

• Maintenance access: Ensure enough space for electricians to reach cables for inspection or replacement. For side-by-side cable trays, a minimum of 600 mm horizontal separation is recommended .
• Stacked installations: When cable trays are stacked vertically, maintain 150 mm vertical clearance between trays and 300 mm from hot pipework to prevent overheating and allow safe access .
• Environmental factors: In humid, high-temperature, or flammable environments, increase spacing and consider fireproof partitions or flame-retardant materials .

Summary

For typical installations, 25 mm horizontal clearance from water pipes is sufficient, but larger distances are required for hot, thermal, or corrosive pipes. Always consider maintenance access, safety, and local electrical codes when planning cable tray layouts. Proper spacing reduces the risk of electrical failures, fire hazards, and facilitates easier inspections and repairs .