Fitness-for-service (FFS) assessment is, as the name suggests, a means to discover whether a structural component is fit for continued operation. The component may contain flaws or other forms of damage, or it may be subject to more severe operating conditions than the original design anticipated.
An FFS assessment typically results in a decision to run as is, repair, replace, or retire the component. A remaining life assessment may also be part of the FFS assessment, which leads to recommendations on future inspection intervals.
Dr. Ted L. Anderson is a principal author of the API 579-1/ASME FFS-1 Fitness-for-Service Standard. He was a founding member of the API Committee that developed the original API 579 Recommending Practice, and he continues to be active in the joint API/ASME FFS Committee that maintains and updates the Standard.