Speaker
Description
Fire Safety Design by means of PBD. The FCC study case
The Future Circular Collider study aims at exploring and designing the required infrastructure and technology for an underground particle accelerator that would span 98km about 400m underground.
A Performance Based Design (PBD) process was launched to assist in the conceptual study phase by evaluating the foreseen safety measures regarding fire and smoke scenarios.
The PBD study stated the safety goals and performance criteria regarding three principal assets: Life Safety, Environment, Property and Continuity of Operation.
Life Safety goal, the first one assessed, was evaluated for occupants, emergency responders and victims (defined as impeded occupants that need to be rescued by the fire brigade). The process required brainstorming sessions with the stackeholders to find the best solutions while accounting for the project necessities and constrains.
The presentation at hand will share an overview of the entire process particularly focusing on the benefits and downsides of conducting this assessment in the early conceptual stage. Additionally it will show the methodology taken to study the survival probability of impeded occupants.
Despite these being a necessary step to build up the risk profile for further perform a cost-benefit impact of safety measures, its treatment is uncommon in the fire safety field. Generally, tenability limits based on visibility, temperature and heat flux are used as hard threshold to stablish the performance criteria; once occupants reached them the criteria is considered unfulfilled. However, in reality, occupants exposed to those limits do not automatically become fatalities but unimpeded evacuees. If a fire brigade intervene, there are some chances to rescue those people.
Given the simple scenario geometry from an evacuation standpoint, 1D egress model was coupled with FDS simulations to quantify the Fractional Effective Dose (FED) received by both, evacuating occupants and victims unable to self-evacuate. The fire rescue operation was also simulated by using some experimental data on blind interventions speeds. Different potential configurations of the in-house fire brigade (regarding locations and personnel) were tested to evaluate the potential benefit of each one.
The results of the overall process show the advantage and ability of PBD approach to design non-standard complex infrastructures that escapes the regulatory framework.
