Ashley Mossa Westinghouse PRA Engineer

Nuclear 411  Fire Protection has been a “hot” topic since the Browns Ferry Fire in 1975  The Main Control Room (MCR) contains instrumentation & control for virtually all plant equipment and is used to shut down the plant  An alternate shutdown panel can be used in case of MCR evacuation  An industry move to a new fire protection program NFPA 805 is costing NPPs millions of dollars in analyses and plant modifications.

Typical MCR

Importance of the MCR  Redundancy & diversity throughout the plant  However MCR is where all instrumentation and controls come together.

Problem Statement  Determine, for a variety of fire sizes, when operators must abandon the control room due to habitability concerns.  Temperature  Heat Flux  Optical Density  Using the data above, determine the probability of operators leaving the control room

Project Steps  Understand FDS  Build FDS Code  Run for a variety of fire sizes & conditions  Analyze results  Determine the probability of operators abandoning the MCR for the ASP

Results for Non-Ventilated Case  Non-vented fires of 400kW or less did not require MCR abandonment Fire Size in kW (HRR) Fastest Time to Damage (minutes)

Questions?