Fireproof cable trays are used for low-voltage wiring

Yes, fireproof cable trays are recommended for low-voltage wiring in environments where fire safety is critical, as they help prevent fire spread and protect electrical systems.

Importance of Fireproof Cable Trays

Low-voltage wiring, such as communication, control, and signal cables, can still pose a fire hazard if exposed to high temperatures or flames. Using fire-resistant cable trays ensures that the wiring remains protected during a fire, maintaining system integrity and reducing the risk of fire propagation . This is particularly important in high-risk environments like hospitals, high-rise buildings, and industrial facilities, where uninterrupted operation and occupant safety are critical .

Material Considerations

• Steel trays are commonly used due to their strength and durability. However, hot-dip galvanized steel offers limited fire resistance because the zinc coating melts at relatively low temperatures, making it suitable only for low-risk areas .
• Stainless steel trays provide structural integrity under heat but do not inherently prevent fire spread, so they are better for corrosion-prone environments rather than fire-sensitive areas .
• Fire-coated steel trays are ideal for high-risk areas, as the coating forms an insulating layer during a fire, significantly reducing fire spread .
• Aluminum trays are lightweight and corrosion-resistant but are less suitable in fire-sensitive environments due to lower heat tolerance .

Installation and Firestopping

Proper installation is crucial for fire safety. Key practices include:

• Layered fire blocking: Fireproof materials should be placed layer by layer to create a compact barrier around cables .
• Fireproof mortar filling: Gaps between cables, trays, and fire-blocking materials should be filled uniformly to prevent fire and smoke penetration .
• Sealing wall and slab penetrations: Openings where trays pass through walls or floors must be tightly sealed with fire-rated boards, firestop packs, or mineral wool to maintain fire integrity .
• Correct sizing of openings: Ensure openings are appropriately sized to allow effective sealing and prevent gaps that compromise fire protection .

Regulatory Guidance

The NEC Article 392 provides guidance on cable tray selection, installation, and support, emphasizing that trays must be robust and suitable for the type of wiring they carry . While low-voltage cables may not carry high current, fireproof trays are recommended in areas where fire risk is significant or where continuity of service is critical.

Conclusion

For low-voltage wiring, fireproof cable trays should be used in high-risk or fire-sensitive environments to protect cables, prevent fire spread, and ensure system reliability. Material choice, proper installation, and adherence to firestopping standards are essential to maximize safety and compliance .