Non-destructive examination can be carried out using the techniques of radiography, ultrasonics and liquid penetrant inspection. Many procedures have been approved by BAe Systems, the US Navy and BNFL and a number of operators are qualified to ASNT Level II standards.
All hot-worked materials are tested by ultrasonic inspection as a mandatory test.  Forgings are also tested by liquid penetrant inspection after machining.  Castings are regularly inspected using specified radiographic and liquid penetrant procedures.