FITNESS-FOR-SERVICE (FFS)
- Home
- Engineering
- Fitness-for-Service
Make Informed Run, Repair, or Replace Decisions
Deteriorating assets, including fixed equipment, structures, foundations, and other infrastructure, cost businesses billions of dollars per year. Assessing the integrity of your in-service equipment will help you proactively solve issues, minimize failures, and save money.
Fitness-for-service (FFS) is focused on plant safety, improving operational performance, and avoiding unnecessary repairs or replacements. E2G conducts FFS assessments to help you increase operational reliability and extend equipment life by making informed run, repair, or replace decisions on your in-service equipment.
Learn More About Fitness-for-Service From E2G's Experts
What is Fitness-for-Service
FFS assessments are conducted on in-service equipment to assess the structural integrity of pressure vessels, piping, and tanks to determine whether the component is fit for continued operation or if the flaw or damage will cause a failure. Implementing FFS into an asset’s lifecycle management program will improve safety, reduce risk, optimize construction, maximize equipment availability, and reduce future maintenance and inspection costs.

Proactive vs. Reactive FFS
FFS assessments are applicable throughout an asset’s lifecycle. E2G recommends conducting proactive FFS assessments to support your facility’s asset integrity management program.
Proactive FFS
When? Proactively review the results of detailed remaining life evaluations, rigorous engineering evaluations, and damage mechanism reviews.
Benefit?
- Extend equipment life and optimize inspection intervals and inspection tasks
- Understand the effects and potential for future damage progression
- Establish screening tools to aid in non-destructive examination (NDE) and flaw sizing exercises
Reactive FFS
When? Conduct FFS assessments when flaws or damage are discovered during equipment shutdown inspections or on-stream inspections.
Benefit?
- Make informed run, repair, or replace decisions on in-service equipment
E2G's FFS Assessment Workflow
Our mechanical and structural engineering team combines the appropriate level of technology with their extensive industry experience to provide practical and cost-sensitive recommendations to challenging FFS problems. Our team offers many related services to help improve the reliability of and extend equipment life, from both a reactive and proactive approach, including:
- Brittle Fracture Screening and Minimum Pressurization Temperature (MPT) evaluations
- Volumetric Metal Loss
- Crack-like Flaw Assessments
- Distortion and Tank Edge Settlement
- Creep and Fatigue Life Estimation
- High Temperature Hydrogen Attack (HTHA)
- Mechanical Vibration of piping systems or equipment
- Fire Damage Assessments
SagePlus software allows you to conduct Level 1, Level 2, and Level 3 FFS analysis using its large set of analysis modules that incorporate the latest API 579 codes. You will achieve safer facilities and plants by evaluating equipment design and in-service conditions to make informed engineering decisions on the life of fixed equipment, piping, and structures. Many users prefer eecWebTools for Level 1 and Level 2 FFS calculations and use SagePlus for in-depth Level 3 calculations.
E2G's Role in Advancing FFS Methodologies
Recommended Reading
- Fitness-for-Service (FFS) /
- Library /
- Mechanical & Structural Engineering /
- Midstream & Pipelines /
- Fitness-for-Service (FFS) /
- HTHA /
- Library /
- Materials & Corrosion /
- Mechanical & Structural Engineering /
- Webinars /
- Fitness-for-Service (FFS) /
- Industry Insights /
- Library /
- Mechanical & Structural Engineering /
- Risk-Based Inspection (RBI) /
- Turnarounds /
- Fitness-for-Service (FFS) /
- Industry Insights /
- Library /
- Mechanical & Structural Engineering /
- Tanks /
- Industry Insights /
- Library /
- Mechanical & Structural Engineering /
- Mechanical Integrity /
- Suitability-for-Service (SFS) /
- Biofuels & Renewables /
- Equity Engineering Practices (EEPs) /
- Industry Insights /
- Library /
- Mechanical & Structural Engineering /
- Re-Use & Re-Purpose /
Fitness-for-Service Expertise
Our mechanical and structural engineering team has completed thousands of FFS assessments for pressure vessels, piping systems, and storage tanks. As pioneers of FFS technologies and lead investigators on many international standards, our team combines their extensive experience with state-of-the-art technology to help extend the lifecycle of your existing assets and create safe operating environments.
Our experts:
- Have 200+ years of combined field experience
- Pioneered development of FFS
- Are the primary authors on WRC 528 and WRC 562
- Serve as lead investigators on API 579 and API 571
- Provide emergency onsite support within 24-hours
- Are the committee leader for the- API 579 Part 3 brittle fracture screening task group

James C. Sowinski, P.E.
Mechanical & Structural Engineering Team Leader
Principal Engineer I














