High-speed rail introduces fire safety challenges that differ from conventional rail systems—and the consequences of failure escalate with speed. At 300+ km/h, safe evacuation can be challenge, especially in tunnels or elevated tracks where external rescue access is limited. In addition, the thermal load from the locomotive can result in elevated tunnel temperatures. This can be particularly challenging with the peak summer temperatures in the Middle East.
Codes like NFPA 130 and TSI provide guidance for fixed guideway transit and fire protection in tunnels but adapt different approaches on how to achieve an acceptable level of safety. The FLS strategy needs to be developed holistically, taking into account other disciplines as well as the requirements of all stakeholders. The goals of fire strategy shall provide an environment for passengers, staff and intervention teams using each part of the railway that is safe from fire and similar emergencies to a practical extent based on the following measures:
1. Protection of occupants who are not intimate with the initial fire development
2. Maximising the survivability of occupants’ intimate with the initial fire development
3. Protect and facilitate the operations of emergency services personnel
4. Maintain rolling stock integrity and afford maximum possible time during an emergency to allow for evacuation and intervention
Prescriptive compliance alone cannot guarantee an acceptable level of safety and the FLS design (as well as other disciplines) need to go through a design assurance process. Typically, this is achieved via HAZID/HAZOP workshops for each asset which would identify any additional hazards which require mitigation. This mitigation would either by implemented into the design or mitigated via operating plans/procedures.
Each aspect of the design also needs careful consideration from a constructability and cost perspective. The CAPEX is a key driver for all projects as this is a major factor in the award of tenders, but careful thought needs to be given to the OPEX of the railway for its lifespan for ensuring safety from day one to the end of the design life of the project. This is particular challenge for high-speed rail projects as the length of the network are much larger compared with the typical metro system, this may also include longer tunnel sections. The difference in the spacing of egress facilities or providing tunnel cooling for these longer tunnel sections have potential exponential impacts to CAPEX/OPEX.