Fireproof sealing of tray-type cable trays

Fireproof sealing for cable trays can be achieved using fire-resistant wraps, blankets, caulks, putty, or fully fire-rated cable tray systems to prevent flame and smoke propagation.

Fire-Resistant Wraps and Blankets

Fire-resistant wraps and blankets are commonly used to encapsulate cable trays, maintaining circuit integrity during a fire. Products like FireMaster® Marine Plus blankets are fully encapsulated in aluminum foil and wrapped around cable trays, secured with steel banding straps. These systems provide 30 minutes of hydrocarbon fire protection for instrument control cables and can be installed with overlaps at elbows and bends to ensure complete coverage . Additional weather protection can be added using corrugated aluminum sheeting.

Firestop Caulks and Moldable Putty

For openings where cable trays pass through walls or floors, intumescent caulks and moldable putty are effective. For example, 3M Fire Barrier Moldable Putty+ and IC 15WB Caulk are UL-listed, pliable, and conformable, allowing them to seal irregular openings while expanding under heat to block fire and smoke . These products are suitable for both new construction and retrofitting existing installations.

Fireproof Cable Tray Systems

Some cable trays are designed to be inherently fire-resistant. Cablofil fireproof cable trays meet stringent standards such as DIN 4102-12, tested at temperatures up to 1000°C for 30, 60, and 90 minutes . These trays are ideal for high-risk environments like power plants, oil and gas facilities, and industrial plants. Complementary accessories, such as Phoenix Cable Cleats, help maintain tray integrity under fire conditions.

Coatings and Tapes

Fire protection coatings and tapes, such as FLAMMOTECT-A and DG-CR 0.7, form a protective shield around cables within trays, preventing flame propagation and enhancing resistance to environmental factors like UV, moisture, and chemicals . These solutions are suitable for indoor and outdoor use and are widely applied in hospitals, airports, and industrial facilities.

Installation Considerations

• Ensure full encapsulation of cable trays, including bends and transitions.
• Use UL-listed or DIN-tested products to comply with fire safety codes.
• Maintain proper overlap and banding spacing for wraps and blankets.
• For penetrations through walls or floors, combine putty, caulk, and firestop pillows to achieve rated fire resistance .
• Regular inspection and maintenance are recommended to ensure continued fire protection.

Summary

Fireproof sealing of cable trays can be achieved through a combination of fire-resistant wraps, blankets, caulks, putty, coatings, and fire-rated trays. Selection depends on the type of cables, environmental conditions, fire rating requirements, and installation constraints. Using certified products and following proper installation practices ensures circuit integrity, smoke containment, and compliance with safety standards during a fire.