Office of Nuclear Regulatory Research

Organizational Performance and Grants Program Team (OPGT) 

The Organizational Performance and Grants Program Team develops, implements, and oversees performance management frameworks and policies to align with the agency’s strategic goals and federal requirements, including setting performance measures, conducting evaluations, and providing analysis to support executive decisions and regulatory effectiveness. It manages all phases of the agency’s University Nuclear Leadership Program (UNLP) , ensuring compliance throughout pre-award, award, monitoring, and closeout, while following relevant statutes, regulations, and policies for federal financial assistance. These efforts support accountability, transparency, and responsible resource management, driving ongoing improvement and higher performance across the agency. 

International Programs Team (IPT) 

The International Programs Team provides RES with comprehensive support for international engagements by coordinating foreign travel, meetings, and interactions with international organizations; managing the initiation and renewal of international agreements and bilateral technical exchanges; evaluating code sharing inquiries; and supporting activities involving foreign assignees. The team ensures that all activities align with the NRC’s International Policy Statement. 

Division of Engineering and Risk Analysis (DERA) 

The Division of Engineering and Risk Analysis plans, develops, and manages research programs that strengthen the technical and risk-informed foundation for NRC regulatory decision-making. The division conducts engineering, materials, human factors, human reliability analysis, and probabilistic risk assessment (PRA) research; develops analytical tools, models, and methodologies to evaluate reactor systems, structures, and components; and resolves safety, security, and technical issues, including generic issues. It evaluates operational and reliability data to identify risk-significant insights and trends; develops and maintains PRA models, performance indicators, and data systems; and implements programs such as the Light Water Reactor Sustainability, Generic Issues, and Accident Sequence Precursor Programs. The division supports the development and application of voluntary consensus codes and standards; and maintains broad technical expertise to provide consultation across the agency. Through its research, analyses, and collaborations, the division recommends improvements to enhance the safety, efficiency, and effectiveness of NRC programs.  

Performance and Reliability Branch (PRB) 

The Performance and Reliability Branch develops and manages research programs that evaluate reliability and operating experience data to generate risk-informed insights for nuclear power reactors and other NRC regulatory applications. PRB supports program offices in assessing licensee performance, develops risk-informed performance indicators for the Reactor Oversight Program, implements the Accident Sequence Precursor (ASP) Program, including producing ASP evaluations and contributions to NRC performance reporting; and manages the Generic Issues Program The branch performs detailed analyses of significant operating events to identify root causes, trends, and lessons learned; coordinates reliability and risk assessment research such as the Risk Assessment Standardization Project; and recommends improvements to enhance the safety, efficiency, and effectiveness of NRC programs. PRB maintains robust processes for collecting, validating, and evaluating operating experience data used across PRA, industry trends, and ASP activities, and applies risk information to support updates to NRC regulations, regulatory guides, and technical bases for licensing, inspection, and enforcement decisions.  

Probabilistic Risk Assessment Branch (PRAB) 

The Probabilistic Risk Assessment Branch develops and manages research programs that advance PRA models, methods, and tools to strengthen risk-informed regulatory decision-making; and plans, develops, and manages the agency’s human reliability analysis (HRA) and fire safety research programs. The fire safety research programs include fire modeling, fire PRA risk analysis models and fire testing programs; and PRAB represents the agency in fire safety research initiatives with external partners on standards development committees and international fire research risk/safety forums. HRA research provides safety perspectives on the impact of human performance on nuclear power plant operations and other NRC-licensed facilities and activities. PRAB coordinates PRA research and standards; develops and applies PRA-based methodologies, including standardized plant risk models and the SAPHIRE code; and provides risk insights on plant design and operation to identify dominant contributors and support risk management strategies. The branch develops regulatory guidance consistent with the Safety Goal and PRA Policy Statements, maintains broad PRA and HRA expertise for agency consultation, participates in domestic and international information sharing activities, and recommends improvements that enhance the safety, efficiency, and effectiveness of NRC programs. 

Materials Engineering Branch (MEB) 

The Materials Engineering Branch conducts research and deterministic analyses to understand and address corrosion, environmentally assisted cracking, and other degradation mechanisms affecting nuclear plant structures and components. MEB performs materials degradation studies, evaluates advanced manufacturing technologies and in service inspection methods, and assesses the reliability of nondestructive examination techniques, including maintaining the agency’s Best Practices ISI resources. The branch collaborates with domestic and international research organizations and maintains expertise in metallurgy, nondestructive examination, physical chemistry, and materials science to provide methods, data, standards, and technical support for NRC regulatory needs related to materials performance and integrity. 

Integrated Systems Engineering Branch (ISEB) 

The Integrated Systems Engineering Branch (ISEB) conducts confirmatory and anticipatory research in electrical engineering, instrumentation and controls (I&C), and human and organizational factors (HOF) to support the identification and resolution of safety and security issues across NRC-regulated facilities. ISEB develops and applies analytical methods, models, and guidance for offsite and onsite power systems, emergency power supplies, equipment qualification, electrical cable aging, digital and software-based safety systems, advanced reactor instrumentation, and emerging technologies and develops and uses HOF methodologies, models, and techniques to evaluate human performance. The branch maintains core technical capabilities and training needed to support current and future program office needs and contributes to modernizing the regulatory infrastructure, including the development and revision of regulations, regulatory guidance, and consensus standards. ISEB coordinates research and technical collaboration with program offices and external domestic and international partners, including the Electric Power Research Institute (EPRI), OECD/NEA, and the U.S. Department of Energy and its national laboratories, to strengthen the technical basis of NRC safety and security decisions. 

Reactor and Structural Engineering Branch (RSEB) 

The Reactor and Structural Engineering Branch (RSEB) conducts analytic and experimental research to develop the technical bases, methods, and tools that support NRC safety and security decisions for operating reactors, advanced non-light water reactors, and other regulated facilities. RSEB maintains expertise in high temperature materials, structural and mechanical system performance, advanced design methodologies, molten salt fuel cycle technologies, materials safeguards, and physical security to ensure readiness for future licensing reviews. The branch develops, maintains, and deploys advanced probabilistic simulation capabilities and integrated analytical methods—including multi physics, artificial intelligence, machine learning, and data analytics tools—to evaluate component and system behavior and structural performance. 

RSEB supports the development, review, and endorsement of consensus codes and standards, including providing technical leadership for ASME Boiler and Pressure Vessel Code (BPVC) Case regulatory guides. The branch fosters collaborative research partnerships with the U.S. Department of Energy, national laboratories, the Electric Power Research Institute, academic institutions, and international organizations to strengthen the scientific foundation of NRC regulatory activities. 

Division of Systems Analysis (DSA) 

The Division of Safety Analysis plans, develops, and manages analytical and experimental research programs that provide the technical expertise, data, models, and simulation tools needed to support reliable, risk informed regulatory decisions. DSA maintains core capabilities in fuels, neutronics, thermal hydraulics, severe accident, accident sequence, source term, radiation protection, radiological consequence, seismic, geotechnical, and other external hazards assessment. The division develops and maintains advanced computer codes and datasets that support independent analyses for licensing and oversight of current, new, and advanced reactor designs, as well as materials users and fuel cycle facilities. DSA conducts research to quantify safety margins, reduce uncertainties, and address areas of high safety or security significance; collaborates with domestic and international research institutions; and develops methods, data, and standards for dose, health effects, and environmental consequence assessments. The division also provides specialized technical consultation across the agency in its areas of expertise. 

Accident Analysis Branch (AAB) 

The Accident Analysis Branch conducts research and analysis on severe accident risk assessment, emergency preparedness, and offsite impacts from possible radiological releases. Additionally, the branch supports regulatory analysis and decision-making involving emerging technologies including artificial intelligence (AI), machine learning (ML), and space nuclear systems. AAB leads the agency's AI regulatory preparedness and decision-making initiatives, which include AI/ML use case investigation and research, evaluating AI impacts on nuclear regulation, and coordinating engagement on AI topics with domestic and international external stakeholders. The branch evaluates health and economic consequences for nuclear power plants, spent fuel storage, nuclear materials transportation, and space nuclear activities, delivering specialized analytical support, code development for the MACCS suite of codes, and risk-informed perspectives. AAB also offers technical consultation to NRC offices regarding safety or licensing decisions, development of guidance, serves on the US interagency nuclear safety review board for space launches, and partners with other federal agencies, universities, laboratories, and domestic and international research centers. 

Fuels and Source Term Code Development Branch (FSCB) 

The Fuels and Source Term Code Development Branch plans, develops, and manages analytical and experimental research to advance, validate, and maintain state-of-the-art computer codes, models, and data needed for neutronics, fuel performance, severe accident progression, and source term analysis. FSCB performs safety analyses for operating, new, and advanced reactors, as well as spent fuel pools and casks; provides technical consultation and develops the analytical bases that support timely, risk informed regulatory decisions; and maintains experimental data and modeling capabilities that underpin NRC safety assessments. The branch partners with domestic and international research organizations to strengthen the scientific and technical foundation of nuclear safety. FSCB is responsible for the NRC’s Cooperative Severe Accident Research Program (CSARP).  

Geotechnical and External Hazards Branch (GEHB) 

The Geotechnical and External Hazards Branch develops and applies the scientific and analytical bases needed to assess seismic, geotechnical, and other external hazards affecting NRC regulated facilities. GEHB collects and evaluates seismic and structural performance data and develops design and analysis methods to support risk informed regulatory decisions. The branch plans, develops, and manages the agency’s external hazard analysis program, including modeling tools, data, and standards for evaluating the magnitude, transport, and environmental effects of radioactive material released beyond facility boundaries. GEHB advances surface and subsurface transport modeling, pathway and contamination assessments, source term characterization, and integrated systems analyses for complex sites. 

The branch maintains expertise in hydrology, geochemistry, radiochemistry, geotechnical and seismic engineering, seismology, geophysics, materials science, and radiobiology to support NRC reviews and assessments of environmental impacts from released radioactive materials. Through these capabilities, GEHB provides independent technical support, reduces key uncertainties in external hazard evaluations, and strengthens the technical foundation for NRC safety and environmental protection activities. 

Radiation Protection Branch (RPB) 

The Radiation Protection Branch plans, develops, and manages research programs that support risk informed regulatory decision-making in radiation protection for nuclear power plants, materials users and facilities, and fuel cycle facilities. RPB serves as an agencywide technical resource in radiation protection and health physics, providing support to NRC program offices and to domestic and international regulatory and scientific counterparts. The branch develops and maintains radiation dose assessment computer codes and databases, analyzes and reports occupational exposure information, and conducts research in radiation dosimetry, low dose science research, and health effects. RPB also leads knowledge management efforts in radiation protection and maintains major agency programs such as the cooperative research code sharing program—Radiation Protection Computer Code Analysis and Maintenance Program (RAMP). 

Code and Reactor Analysis Branch (CRAB) 

The Code and Reactor Analysis Branch develops, maintains, and applies state-of-the-art computer codes, models, and experimental databases to evaluate neutronic, thermal-hydraulic, and reactor system behavior under normal, abnormal, and accident conditions for current, new, and advanced reactors. The branch conducts analytical and experimental research to quantify safety margins, reduce uncertainties, and support risk-informed regulatory decisions; maintains essential capabilities in reactor physics, system thermal-hydraulics, multi-physics, and computational fluid dynamics; and performs independent analyses to support licensing and oversight. CRAB collaborates with universities, laboratories, and domestic and international research centers, and provides technical consultation to NRC program offices using its maintained analytical tools, data, and knowledge bases to ensure reliable and technically sound regulatory evaluations. CRAB is responsible for the NRC’s Code Applications and Maintenance Program (CAMP). 

Division of Technical Training (DTT) 

The Technical Training Division provides leadership and agencywide management of NRC training and development programs that ensure employees possess the technical, regulatory, and professional skills needed to meet current and future mission demands. The division maintains and implements the NRC Training and Development Strategic Plan; coordinates policy development with headquarters offices and regions; and delivers integrated regulatory, technical, and professional training, including support for programs such as the Nuclear Regulator Apprenticeship Network. TTC leads NRC knowledge management activities to preserve core competencies, oversees the agency’s consolidated training budget, and manages TTC facilities, capital assets, and associated information technology systems and networks. The division provides technical assistance to NRC programs, supports training for foreign regulatory counterparts, and drives NRC’s learning transformation by enabling a modern, technology enhanced, accessible learning environment that advances mission readiness and empowers employees in their professional development. 

Reactor Technology Training Branch (RTTB) 

The Reactor Technology Training Branch (RTTB) manages and delivers the NRC’s reactor technology training curriculum across major commercial and advanced reactor designs, providing classroom instruction and full scope simulator training to build and maintain the reactor technology and regulatory assessment competencies required of NRC inspection and technical staff. RTTB develops new and updated courses to meet evolving agency needs; trains staff in performance based safety assessment areas such as control room configuration, integrated plant operations, and application of emergency and severe accident procedures; and oversees interagency agreements and commercial contracts supporting reactor training. The branch ensures reactor technology training aligns with the NRC Strategic Plan, provides expert technical assistance to domestic and international regulatory partners, and manages specialized training software and hardware—including full scope simulation systems—used in formal NRC qualification and training programs. 

Specialized Technical Training Branch (STTB) 

The Specialized Technical Training Branch (STTB) manages the NRC’s specialized technical training programs and the Learning Innovation and Support Team, delivering and coordinating training that supports staff qualification requirements and Agreement State needs under the National Materials Program. STTB provides and maintains specialized curricula in probabilistic risk assessment, engineering support, radiation protection, fuel cycle technology, security and safeguards, and regulatory skills, while developing new courses and updating existing ones to meet evolving agency competencies. The branch oversees interagency agreements and commercial training contracts, offers expert technical assistance to domestic and international regulatory partners, and ensures all specialized training aligns with the NRC Strategic Plan. STTB advances learning transformation by modernizing NRC training through instructional design best practices, active learning, blended and online delivery, learning technology integration, and competency based training to assess and strengthen both individual and organizational skill needs. The branch enhances NRC learning programs by analyzing training needs, providing consulting services to ensure training design is closely related to performance outcomes, and evaluating learning effectiveness.  The branch also maintains training processes, systems, and program policies for the division, ensuring effective, innovation driven support for the agency’s mission. 

Nuclear Regulator Apprenticeship Network Branch (NRANB) 

The Nuclear Regulator Apprenticeship Network Branch (NRANB) manages NRC staff development programs that build technical capability, preserve institutional knowledge, and support long term human capital needs. The branch administers the 18 month Nuclear Regulator Apprenticeship Network (NRAN) program to develop regulatory knowledge and practical experience for new apprentices, provides mentoring opportunities that strengthen individual employee growth, and leads the agency’s Knowledge Management (KM) Program by coordinating research, development, and implementation of strategies to capture, transfer, and share critical knowledge in support of mission performance.