Cable Tray Resting on Copper Medical-Gas Pipework
Zinc-plated electrical cable trays were installed in direct contact with and supported by copper medical-gas pipes. Medical-gas pipework must not be used to support electrical containment, and each service should have its own independent support system with the specified separation maintained. Direct contact can impose unintended loads on the pipework and cause movement, vibration, abrasion or damage to the copper surface. Contact between dissimilar metals in the presence of moisture may also accelerate corrosion of the zinc coating. Any damage or movement of medical-gas pipework could compromise a safety-critical supply, so the tray must be independently supported and the affected pipes inspected by a competent medical-gas specialist before commissioning.
- NCQLE reference
- NCQLE-2026-00020
- Quality topic
- Installation quality
- Lesson type
- Failure
- Evidence rating
- Experience
- Published
- 1 August 2026
- Last reviewed
- 1 August 2026
Evidence basis: Supported by relevant professional experience. This learning is provided for professional consideration and does not replace project-specific competent advice, statutory duties or contractual requirements.
Context
A visual inspection cannot confirm the extent of loading, abrasion, corrosion or concealed damage to the pipework, or whether the services were temporarily positioned before final support. Required clearances and support arrangements depend on the approved medical-gas design, project specification and applicable healthcare guidance. Medical-gas pipework must not be moved, repaired or tested by general trades; any assessment or remedial work must be completed by a competent medical-gas specialist under the project’s permit and commissioning procedures. During inspection, zinc-plated electrical cable trays were found resting directly against the copper medical-gas pipework rather than being independently supported with suitable separation. This placed unintended load onto the pipes and created points where movement or vibration could cause abrasion and surface damage. The direct contact between dissimilar metals also raised concerns about possible corrosion where moisture was present. The installation created an avoidable risk to the integrity of a safety-critical medical-gas system.
The transferable lesson
Medical-gas pipework must never be used to support cable trays or other building services. Each service requires its own independently designed supports, with the specified clearance maintained between pipework and electrical containment. Proper coordination is essential because direct contact can cause unintended loading, abrasion, vibration and corrosion, potentially compromising a safety-critical gas supply.
Recommended action
Coordinate medical-gas pipework and electrical containment before installation, showing their routes, support systems and required separation on approved drawings. Provide each service with independent supports and check clearances at crossings and congested areas. Include these interfaces within the inspection plan and inspect them before ceilings are closed. Where contact has occurred, reposition and independently support the cable tray, then have the medical-gas pipework inspected and tested by a competent medical-gas specialist before commissioning.