Does the shaft have fireproof cable trays

Cable trays inside shafts are not inherently fireproof, but they are typically installed with fireproofing measures and fire-rated sealing to prevent fire spread.

Fireproofing Measures for Cable Trays

Cable trays in shafts are generally made of steel, aluminum, or fiberglass-reinforced plastic, which provide mechanical strength but are not fully fireproof on their own . To enhance fire safety, fire barriers or fire-rated materials are installed within or around the trays to isolate different fire zones and prevent flames from spreading along the shaft . When trays pass through walls, floors, or slabs, openings are sealed using fire-rated penetration sealing materials, such as firestop packs, firestop mastic, or fire-resistant mineral wool .

Firestopping and Sealing

Firestopping is critical in shafts to maintain the integrity of fire-rated compartments. Openings around cable trays are tightly sealed, often with fire-resistant backing plates for large gaps, and the gap between firestop packs and cables is kept minimal to ensure effectiveness . UL-listed systems, such as 3M fire barrier pillows or moldable putty, are commonly used to seal penetrations and provide thermal insulation, smoke containment, and structural integrity during a fire . The sealing process ensures that all gaps inside and around metal trunking are completely filled, both internally and externally .

Inspection and Maintenance

Fireproof cable trays require regular inspection to ensure the coating integrity, sealing effectiveness, and absence of corrosion or mechanical damage . Any abnormalities, such as deformation or compromised fireproofing, should be addressed immediately to maintain long-term fire safety.

Summary

While the trays themselves are not fully fireproof, the combination of fire-resistant tray materials, fire barriers, and proper firestopping ensures that cable trays inside shafts meet fire safety requirements. This approach prevents fire and smoke from spreading through the shaft and maintains the integrity of the building's fire-rated compartments .