This Safety Guide provides recommendations to the designers of nuclear power plants for a comprehensive safety assessment in the initial design process and for modifications to the design, as well as recommendations to operating organizations for independent verification of the safety assessment for new nuclear power plants. The guidance can also be applied to safety reviews for existing plants. The methods and recommendations can be used by regulatory bodies for the conduct of the regulatory review and assessment. The Safety Guide recommends how to meet the requirements established in Safety Standards Series No. NS-R-1, The Safety of Nuclear Power Plants.