Air Compressor Piping and Cable Trays

Air compressor pipes cannot be installed inside cable trays containing electrical cables, but certain lightweight plastic pipes can be mounted on or alongside cable trays safely.Regulatory RestrictionsAccording to the National Electrical Code (NEC), cable trays are intended solely for electrical conductors and cannot contain pipes or tubes for air, water, gas, or other mechanical services (NEC 300.8) . Installing compressed air pipes inside a cable tray with electrical cables is therefore not permitted, as it could create safety hazards including electrical interference, fire risk, or damage to cables.Practical Installation OptionsWhile pipes cannot run inside cable trays with electrical cables, they can be supported by the cable tray structure if properly engineered. For example, mechanical engineers may use cable trays as a support for air piping, provided that:The tray is designed to handle the additional load of the pipes.Engineering documentation (e.g., P.E. stamped drawings) confirms the tray's load capacity .Pipes are mounted adjacent to the tray using supports like Unistrut or pipe clips .Material ConsiderationsPlastic pipes (e.g., polyethylene) are lightweight and can be fixed into or onto cable trays using pipe clips or cable ties, reducing installation costs and maintaining safety since plastics do not conduct electricity .Metal pipes (e.g., galvanized steel) are heavier and require careful support; they cannot be placed inside cable trays with electrical cables and must be mounted separately to avoid overloading the tray or creating hazards .Care must be taken to avoid heat exposure, sudden pressure release, or mechanical damage, especially near compressors where air temperature may be elevated .Safety and SpacingEven when pipes are mounted alongside cable trays, adequate separation is essential to prevent heat transfer, vibration, or chemical exposure from affecting electrical cables . Maintaining proper spacing ensures both systems operate safely and reduces the risk of electrical failures or fire.SummaryDo not install air compressor pipes inside cable trays with electrical cables.Lightweight plastic pipes may be mounted on or alongside cable trays with proper support.Metal pipes must be supported separately and cannot share the tray with electrical conductors.Always follow NEC regulations, manufacturer guidelines, and engineering documentation to ensure safety and compliance.