List of Fireproofing and Sealing Holes for Cable Trays

Key fireproofing items for cable trays include firestop putty, intumescent caulks, fire-resistant mineral wool, firestop packs, and protective coatings or tapes.

Firestop Putty and Moldable Materials3

M Fire Barrier Moldable Putty+: A one-part, halogen-free putty used to firestop electrical outlet boxes, cable trays, conduits, and insulated pipes. It is pliable, adheres to most surfaces, and conforms to irregular openings, making it suitable for retrofits and new installations (Eaton),. Moldable putty sticks (FSP-MPS): Used in combination with firestop pillows to seal openings around cable trays, ensuring UL-listed fire protection (Eaton),.

Intumescent and Firestop CaulksIC 15WB Caulk: A premium, intumescent latex/water-based caulk that expands under heat to contain fire and smoke. It can be applied with a standard caulking gun and is suitable for sealing gaps around cable trays and wall/floor penetrations (Eaton),. Firestop mastic: Used to seal gaps and voids around cables and trays, providing a flexible, fire-resistant barrier (AllPCB),.

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Resistant Packing Materials

Firestop packs: Mineral wool or other fire-resistant packing materials inserted into openings before sealing. They are placed in an orderly sequence, with gaps not exceeding 1 cm² and minimum packing thickness of 24 cm for effective fire containment (AllPCB),. Fire-resistant backing plates: Installed for large openings to support firestop materials and ensure complete sealing (AllPCB),.

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Resistant Coatings and TapesFLAMMOTECT-A coating: A fire protection coating applied directly to cables or trays to prevent flame propagation and maintain cable functionality during fire events (Flamro),. DG-CR 0. 7 fire protection tape: Wraps around cables to provide a protective shield against fire, UV, moisture, and chemicals (Flamro),.

Fireproof Tray Components

Fireproof cable trays: Use trays made of painted steel, galvanized steel, aluminum alloy, or fiberglass-reinforced plastic depending on environment. Only fireproof trays should be used for flame containment or isolation (Zero Instrument),. Splice plates and mounting hardware: For “CT” type trays, use zinc-plated splice plates to maintain structural integrity while allowing firestop installation (Eaton),.

Installation Considerations

Ensure openings are tightly sealed without visible cracks or voids. Maintain proper clearance between cables to avoid heat accumulation. Periodically inspect trays and fireproofing materials for corrosion, damage, or degradation to ensure long-term effectiveness (Zero Instrument),.

By combining these materials—putty, caulks, mineral wool, firestop packs, coatings, and fireproof trays—you can achieve effective fireproofing and sealing of cable tray penetrations in walls, floors, and ceilings while complying with UL and fire safety standards.