Materials and full-scale testing Design criteria Design analysis Material selection and life predictions Manufacturing and fabrication Structural component in-service In-service failure Structural aging or malfunction fit service concern Nondestructive Field perating inspections examinations conditions Mechanical Microscopic Fracture Laboratory Deposit and and physical examinations aminations surface chemical property test analysIs analysis Materials characterized Failure mechanism identified Environmental factors established ComponentFracture Engineering StructuralIOperations testing mechanics analyses analysis evaluation Root cause determined Fit for service Not fit for service Corrective Identify next Repair or Remove Replace with nspection interval I restrict service from service new structure ig. 1 Flow diagram showing the relationship between the design phase and the investigative tasks for in-service failure structural aging and fitness-for-service of structural components One alternative for avoiding failures used in the past was to overdesign and to operate overconservatively. The economic nalties for both are increasingly significant; however, the economic penalties for failures are significant as well. It isFig. 1 Flow diagram showing the relationship between the design phase and the investigative tasks for in-service failure, structural aging, and fitness-for-service of structural components One alternative for avoiding failures used in the past was to overdesign and to operate overconservatively. The economic penalties for both are increasingly significant; however, the economic penalties for failures are significant as well. It is