Plutonium research and development activities have resided at the Los Alamos National Laboratory (LANL) since 1943. The function of the Plutonium Facility (PF-4) has been to perform basic special nuclear materials research and development and to support national defense and energy programs. The original Final Safety Analysis Report (FSAR) for PF-4 was approved by DOE in 1978. This FSAR analyzed design-basis and bounding accidents. In 1986, DOE/AL published DOE/AL Order 5481.1B, ''Safety Analysis and Review System'', as a requirement for preparation and review of safety analyses. To meet the new DOE requirements, the Facilities Management Group of the Nuclear Material Technology Division submitted a draft FSAR to DOE for approval in April 1991. This draft FSAR analyzed the new configurations and used a limited-scope probabilistic risk analysis for accident analysis. During the DOE review of the draft FSAR, DOE Order 5480.23 ''Nuclear Safety Analysis Reports'', was promulgated and was later officially released in April 1992. The new order significantly expands the scope, preparation, and maintenance efforts beyond those required in DOE/AL Order 5481.1B by requiring: description of institutional and human-factor safety programs; clear definitions of all facility-specific safety commitments; more comprehensive and detailed hazard assessment; use of new safety analysis methods; and annual updates of FSARs. This paper describes the safety analysis report (SAR) upgrade program at the Plutonium Facility in LANL. The SAR upgrade program is established to meet the requirements in DOE Order 5480.23. Described in this paper are the SAR background, authorization basis for operations, hazard classification, and technical program elements.