Fire-resistant (FR) cables are specialized electrical cables designed to maintain their electrical integrity and functionality for a specific duration during a fire, ensuring power to critical safety systems like emergency lighting, alarms, and smoke extractors, enabling safe evacuation and firefighting. They achieve this through specialized materials like mineral insulation or silicone rubber and halogen-free sheaths that resist extreme heat, prevent flame spread, and emit minimal toxic smoke, unlike standard cables.
Key Characteristics
- Circuit Integrity: They keep essential circuits operational, unlike standard cables that fail quickly in fire.
- High Heat Resistance: Built to withstand temperatures up to 300°C or more for a set time (e.g., 30, 60, 90 minutes), as defined by standards like IEC 60331.
- Low Smoke & Zero Halogen (LSZH): Often use LSZH sheaths to reduce toxic smoke and corrosive gases, improving visibility for escape and rescue.
- Specialized Construction: Incorporate mica tapes, ceramic fibers, or silicone rubber for insulation.
Common Applications
- Public Buildings: Hospitals, airports, tunnels, subways, offices.
- Industrial Facilities: Power plants, laboratories, manufacturing sites.
- Safety Systems: Fire alarms, emergency lighting, smoke ventilation, water pumps.
Fire Resistant vs. Flame Retardant
- Fire Resistant (FR): Continues to function for a time during fire (circuit integrity).
- Flame Retardant (FRR): Prevents fire from spreading along the cable but may not maintain functionality.
