Written for use by operating organizations of nuclear power plants and regulatory bodies, this Safety Guide provides specific recommendations on maintenance, testing, surveillance and inspection to ensure that the levels of reliability and availability of all structures, systems and components important to safety remain in accordance with the assumptions and intent of the design, and also that the safety of the plant is not adversely affected after the commencement of operation. The publication covers the establishment and implementation of preventive and corrective maintenance programmes; testing surveillance and inspection; the repair of defective plant equipment; the provision of related facilities and equipment; procurement; and generating and retaining records of maintenance activities.