The U.S. Nuclear Regulatory Commission's (NRC's) Office of Nuclear Regulatory Research (RES) and the Electric Power Research Institute (EPRI) have recently issued a joint publication documenting consensus procedures for a state-of-the-art nuclear power plant (NPP) Fire Probabilistic Risk Assessment (FPRA). This consensus methodology has resolved many past fire PRA weaknesses, including those issues identified by the NRC, based on the Individual Plant Examination for External Events (IPEEE) process. The study also identified a number of remaining analytical challenges that were not fully addressed by the new methodology. This paper will discuss these identified analytical challenges where additional research may be...