Tunnel Fire Risk
Abnormal temperature rise and fire development in enclosed road, rail and metro tunnel environments.
Transportation
Transportation Infrastructure Monitoring
Fiber Optic Monitoring for Tunnels, Transit Hubs and Secure Transport Networks
REQUEST A QUOTE
CONTINUOUS TRANSPORTATION MONITORING
Continuous Monitoring Across Transportation Assets
Road, rail and metro tunnels, airports and seaports operate under different conditions, but they share one requirement: problems must be located quickly without interrupting service.
Tunnels require thermal safety across enclosed routes. Airports and seaports add electrical systems, baggage handling, fuel areas, perimeter security and utility corridors.
FOTAS addresses these risks with Distributed Temperature Sensing (DTS) and Distributed Acoustic Sensing (DAS).
DTS measures temperature along the sensing fiber, while DAS detects acoustic and vibration activity around the cable. The technologies work independently or within one monitoring architecture.
MONITORING CHALLENGES
Key Transportation Monitoring Challenges
Transportation assets are difficult to inspect continuously. Access may be restricted, maintenance windows are short and many systems must remain operational. Tunnels introduce dust, humidity, vibration and high-voltage equipment. Airports and seaports add outdoor exposure, salt, heavy traffic and restricted areas.
Electrical Overheating
Thermal faults affecting cables, joints, motors, bearings, substations and electrical equipment.
Ventilation and Smoke Control
Ventilation faults and incomplete thermal information during normal operation or emergency response.
Restricted Area Intrusion
Unauthorized access, fence interference and movement around controlled transportation infrastructure.
Excavation Near Cable Routes
Construction and digging activity close to communication, signaling and utility corridors.
Cargo and Fuel Areas
Fire and equipment risks across fuel handling, cargo storage and bulk-material operations.
DTS FOR TUNNELS
FOTAS DTS for Tunnels and Thermal Safety
Distributed linear temperature monitoring for road, rail and metro tunnel environments.
Distributed Temperature Sensing
Continuous Tunnel Temperature Profiling
FOTAS DTS uses optical fiber as a linear temperature sensor. The control unit sends laser pulses through the fiber and analyzes Raman backscatter to calculate temperature along the route.
In road, rail and metro tunnels, the sensing cable is generally mounted near the ceiling, with its position defined by tunnel geometry and airflow.
Alarm logic may combine fixed temperature thresholds, rate-of-rise criteria and differential temperature profiles. When an abnormal event develops, the system identifies the affected section and passes the alarm to connected safety systems.
- Road, rail and metro tunnels
- Power cables and cable trays
- Signaling and electrical equipment
- Ventilation and smoke-control systems
- Transformers and substations
One-Meter Reading Intervals
The tunnel configuration described in the FOTAS Application
Note provides temperature readings at one-meter intervals.
±1°C Temperature Accuracy
Supports reliable thermal monitoring and alarm management
across the tunnel route.
Safety System Integration
Supports ventilation, smoke extraction, suppression and
evacuation procedures.
AIRPORTS AND SEAPORTS
Thermal Monitoring for Airports and Seaports
Distributed temperature information across electrical, mechanical, cargo and underground infrastructure.
An airport or seaport may include terminals, substations, utility tunnels, baggage systems, conveyors, storage zones and fuel infrastructure. DTS follows these assets with a sensing route instead of relying only on isolated points.
Airports
Baggage, Electrical and Underground Systems
Temperature trends reveal overheating motors, bearings, rollers and friction points on baggage systems. Along electrical routes, DTS identifies hot connections and developing cable faults.
Seaports
Cargo, Conveyor and Jetty Infrastructure
DTS monitors bulk-material conveyors, container storage areas, electrical routes, jetty infrastructure and selected pipeline sections.
Technical Note
For port pipelines, thermal monitoring supports wider leak detection strategies, but it is not a universal leak detector.
DAS SECURITY
FOTAS DAS for Perimeters and Transport Corridors
Distributed acoustic and vibration monitoring for restricted boundaries and critical infrastructure routes.
Distributed Acoustic Sensing
Perimeter and Corridor Protection
FOTAS DAS converts fiber into a distributed acoustic and vibration sensor. Fence-mounted, buried and hybrid installations support airport and port boundaries, restricted corridors and external communication routes.
Deep-learning analytics classify walking, digging, vehicle movement, fence climbing and fence cutting. Environmental filtering reduces nuisance alarms, while location data helps security teams direct cameras or patrols.
- Airport and seaport perimeter fences
- Buried approach and restricted zones
- Communication and utility corridors
- Excavation near external fiber routes
- Vehicle and pedestrian movement
Selected FOTAS DAS Configurations
Monitoring distances up to 100 km and location accuracy
down to 4 m, depending on the model, installation and
site conditions.
INTEGRATION AND PASSIVE SENSING
Integration, Passive Sensing and Deployment
DTS and DAS control units are installed in control rooms or equipment rooms. Monitoring data connects to SCADA, BMS, tunnel management, fire alarm and security platforms.
Tunnel designs may use Modbus communication and hardwired relay outputs for integration with operational and fire-safety systems.
The sensing fiber is passive and requires no electrical power along the monitored route. It is also immune to electromagnetic interference, which is valuable near traction power, signaling systems, substations and heavy electrical equipment.
DEPLOYMENT FACTORS
Key Deployment Considerations
Successful deployment depends on decisions made during the design stage. These details determine alarm quality and the accuracy of location information.
Explore the FOTAS Technology Guide.
Explore the Technology Guide
Learn how DTS and DAS support fire safety, asset monitoring and security across critical infrastructure.
Transportation Monitoring
Monitor Critical Transportation Infrastructure
Talk to our engineering team about a FOTAS DTS or DAS configuration for tunnels, airports, seaports and secure transport corridors.