Equipment qualification testing - a practical approach

When nuclear safety equipment is credited with a Required Safety Function it must properly perform that function to facilitate safe control and/or shutdown of the plant during a design basis accident. When such equipment is required to be environmentally (EQ) and/or seismically qualified (SQ) for safety related use in CANDU nuclear power plants, the preferred method of qualification is by type testing. The qualification testing process requires that the test specimen equipment be subjected to the aging stressors associated with the normal service conditions that it would experience during it's required qualified (or service) life. Following the aging process, the test specimen is in a condition representative of that in which it would be at the end of its service life in the plant. The test specimen is then subjected to a simulated accident during which it must satisfy performance requirements thereby demonstrating that it can perform its required safety function. The performance requirements specified for the qualification testing must be designed to ensure that satisfactory performance of the safety function is demonstrated during the qualification program. This paper provides descriptions of practical methods used in the deriving and satisfying of relevant performance requirements during the qualification testing of safety related equipment. (author)