Model each area and operating mode
Station halls, equipment rooms, control centres and tunnels need separate airflow and risk assumptions.
Application · Rail and rapid transit hubs
Aspirating smoke detection for rail transit
Rail-transit ASD should be divided by area and operating condition. Stations, technical rooms, control centres and tunnels have different airflow, contamination, access and interface requirements. A common hole layout or alarm threshold should not be applied across all of them without separate verification.
Risk conditions that
change the design
The sampling network must respond to the real environment and operating modes.
- 01Piston effects and ventilation changing smoke movement
- 02Metallic dust and environmental contamination
- 03Different conditions in public and technical areas
- 04Restricted operational maintenance windows
Design priorities
Resolve these conditions before model and network confirmation.
Design for the maintenance window
Place detectors, filters and test points where isolation, testing and reset can be completed within operational access rules.
Manage dust and pressure
Filter, blow-through and pressure effects must be checked against the airflow monitoring range and service interval.
Define the interface boundary
Staged alarms, ventilation, access control, public address and the fire alarm system must follow the overall fire strategy.
Protection layers
Each layer should have a defined detection and response purpose.
Technical rooms
Local or room-level sampling for electrical, communications and control equipment.
Public spaces
Sampling coordinated with large-space smoke behaviour, ventilation, ceilings and passenger management.
Tunnels and long-distance areas
Design focused on piston airflow, mechanical ventilation, dust, pressure and maintainability.
Operations and service
Filters, tests, isolation and reset are incorporated into a practical maintenance window.
Inputs required before design
These inputs turn an application concept into an auditable technical decision.
| Parameter | Why it matters | Design output |
|---|---|---|
| Area type | Public, technical and tunnel areas have different risks and airflow. | Zoning and system structure |
| All ventilation modes | Normal, night and fire modes change smoke travel. | Sampling positions and test modes |
| Dust and pressure conditions | Affects airflow monitoring, filtration and service. | Environmental accessories |
| Operations and maintenance window | Controls detector, test and isolation access. | Service and testing method |
Candidate models
A candidate remains provisional until project inputs and approval scope are reviewed.
Questions to resolve
Use these in the first project workshop.
- 01Is the area public, technical, control-centre or tunnel space?
- 02What are the normal, night and fire ventilation modes?
- 03Which product approvals, materials and interfaces are mandatory in the destination market?
Common questions
Can one ASD design be used across every rail-transit area?
No. Station halls, equipment rooms, control centres and tunnels have different ventilation, contamination, maintenance and interface conditions. Each needs a defined protection objective and calculated network.
How does piston airflow affect ASD sampling?
Piston airflow changes smoke direction, dilution and pressure at sampling holes. The design must check different train and ventilation modes and confirm the installed response through functional testing.
Source and review record
Manufacturer facts: SECURITON SecuriSmoke ASD Product Brochure V2.0 EN and current manufacturer design documentation. Application sequence and candidate-model guidance are PEIEN engineering recommendations.
Last reviewed: 27 July 2026. Project values remain assumptions until reviewed by a suitably qualified fire professional or experienced ASD practitioner.
Apply the guidance to your project.
Submit the destination country, application, area, environment, drawings and project stage for a first selection review.