End-of-Life, Remaining-Life, and Fitness-for-Service Assessments

When evaluation of inspection results suggest that an asset is near its end of useful life, Asset Optimization Consultants can assist with Fitness for Service evaluations to determine if the asset is suitable for continued operation. Asset Optimization experts are experienced performing Level 1, 2, or 3 FfS assessments.
End-of-Life, Remaining-Life, and Fitness-for-Service Assessments

Fitness for service (FFS) is a methodology to determine the adequacy of a structure for continued service when it contains a flaw or is operating in a particular condition where there is risk of failure. Failure conditions and types of flaws may include:

  • brittle fracture
  • fire damage
  • geometrical irregularities
  • general corrosion / erosion
  • local metal loss
  • pitting corrosion
  • blisters
  • crack-like flaws

Cracking flaws may include:

  • amine cracking
  • ammonia cracking
  • carbonate cracking
  • hydrogen damage (H2S, HF)
  • hydrogen attack
  • caustic cracking in SS
  • chloride cracking in SS
  • polythionic cracking in SS

API RP 579 provides the methods and procedures intended to supplement and improve requirements of API 510, API 570, API 653 and API 750.

AOC consultants include engineering personnel with expertise in FFS assessments. We offer three levels of assessment per API RP 579.


  • Conservative screening
  • Minimum amount of inspection or component information
  • Plant inspection or engineering personnel

Level 2

  • More detailed less conservative with more accurate results
  • Inspection information similar to that of Level 1
  • Qualified engineering personnel

Level 3

  • The most detailed evaluation
  • The most detailed inspection and component information
  • Recommended analysis procedures based on numerical analysis techniques such as the finite element method

Service Inquiry

Related Services

Inspection Services

Asset Optimization's Inspection Group provides our partners with comprehensive inspection resources to further support our internal needs and the needs of our partners. Consisting of both API-certified inspectors and ASNT-compliant technicians, our inspection team offers a variety of visual inspection and NDE services.

Risk Based Inspection (RBI) Implementation and Planning

AOC has delivered thousands of sustainable Risk Based Inspection (RBI) programs earning the trust of owner operators.

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RBI/MI Overview

What is Risk Based Inspection?

API 580 RBI Overview

What impact does Risk Based Inspection (RBI) have on my organization?

API 580 Training

Is your Risk Based Inspection (RBI) program aligned with the API 580 Recommended Practice? Are you ready for certification?

API 581 Overview

What's actually going on inside all of that fancy software? An introduction to the API 581 methodology.

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