In July 2025, we completed a fire monitoring system for an underground utility tunnel at P Steelworks in Gwangyang.

The system covers the outgoing and return routes of a 500-meter tunnel, divided into 16 fire detection zones. It consists of a repeater incorporating DTS, fiber optic sensing cable, a combined fire alarm receiver, a database server and an HMI.

The fire alarm receiver is connected to the relevant fire safety departments and agencies. The database server and HMI can display either fire detection zones or tunnel temperatures at one-meter intervals.

After installation, the optical cable was heated in each zone to verify alarm activation, location identification and alarm transmission.

The HMI uses drawings resembling the actual site and supports both one-meter monitoring and zone-based display and alarms consistent with the fire alarm receiver.

Topics: underground tunnel and utility tunnel fire monitoring, one-meter fire detection, distributed temperature monitoring, DTS and fiber optic fire sensing.