Fitness for service assessment may be required, because the equipment may:

• Contain Flaws Such as Locally Thin Areas (LTAs) or Cracks
• Not Meet Current Design Standards
• Operate Under More Severe Conditions than Originally Expected

The main products of fitness for service assessment are (1) decisions to run, alter, repair, monitor, or replace equipment and (2) guidance on equipment inspection intervals.

Fitness for service assessment employs analytical methods, mainly stress analysis, to evaluate flaws such as locally thin areas and cracks as well as damage such as dents, bulges, and distortions.