A New ASME Standard: Plant Systems Design

The draft ASME Plant Systems Design standard (PSD-1) provides a new approach to design of nuclear and other plants with potential for significant hazards to the health and safety of the public, the worker, and the environment. The objectives of PSD-1 are to improve integration of health, safety, and environmental risk evaluations with design; reduce new plant design, construction, commissioning, and life cycle costs; reduce licensing and construction uncertainty; and improve operating plant availability. PSD-1 includes requirements and guidance, for design organizations to incorporate risk informed probabilistic design methodologies with traditional deterministic design methods using reliability and availability targets. It integrates systems engineering, qualitative and quantitative risk evaluations, and probabilistic design methods into traditional design processes. The risk evaluation processes integrate safety risk evaluations with production risk evaluations to increase performance over the plant life cycle. Risk evaluation processes also integrate current industry and regulatory concepts of defense-in-depth, safety significance, as well as risk-informed and performance-based design into a seamless design process. The PSD committee follows a systems engineering process and is writing the standard in a Model Based Systems Engineering tool. This paper provides an introduction and overview of the new standard that is targeted for publication in 2025.