Fire-retardant paint for cable tray connecting pieces

Water-based intumescent or fire-retardant paints are recommended for protecting cable tray connections while maintaining fire safety and cable integrity.

Recommended Paint Types

Water-based intumescent coatings are widely used for cable tray systems and connecting pieces. These paints expand under heat to form an insulating char layer, slowing heat transfer and preventing flame spread along cable runs. Examples include AF Cable Coat, a water-based fireproof paint certified under IEC 60332-3-10 and IEC 60332-3-22, which releases water vapor when exposed to fire and leaves a non-combustible residue, limiting fire damage to localized areas (AF Systems) . Another option is Service Coat FR-1, an acrylic-based intumescent coating suitable for cables, cable trays, and metal pipes, designed to maintain circuit integrity during a fire (Protecta) .

Compatibility with Cable Materials

For LSOH or PVC-sheathed cables, water-based paints are generally safe and do not compromise low smoke or zero halogen properties. Oil-based or organic solvent paints should be avoided, as they can cause swelling, softening, cracking, and increased smoke or halogen gas emission during a fire (Prysmian, FIA) . Always verify the paint's Safety Data Sheet (SDS) and ensure it is compatible with the cable type.

Application Guidelines

• Apply coatings evenly on connecting pieces and along the tray surface, controlling thickness according to manufacturer specifications.
• For linear cable runs, AF Cable Coat recommends applying the paint on a linear metre every 20 metres for horizontal sections to ensure fire containment .
• Intumescent coatings are best applied in new builds or areas requiring smooth, cavity-free surfaces for inspection and maintenance, while fire wrap systems may be preferred for retrofits or irregular routing (Apex Tray) .
• Document all painting in inspection or service records, and label cables if markings are obscured to maintain compliance with fire safety standards (FIA) .

Key Considerations

• Fire performance: Ensure the paint is certified for flame retardancy and fire endurance.
• Durability: Water-based intumescent paints maintain elasticity and resist temperature-induced movement.
• Maintenance: Intumescent coatings are easier to inspect visually but may require careful repair if damaged.
• Compliance: Follow local building codes and standards such as IEC 60332 and BS 502002 for fire-resistant cable installations. Using water-based intumescent or fire-retardant paints on cable tray connecting pieces provides effective fire protection while preserving cable integrity and compliance with safety standards.