Introduction: Who is API TES for and Why It Matters
API TES (Tank Entry Supervisor) is a globally recognized certification offered by the American Petroleum Institute (API). It is designed specifically for professionals who supervise the entry of workers into aboveground storage tanks (ASTs). These environments involve hazardous conditions such as toxic gases, oxygen deficiency, and confined-space risks making proper supervision essential.
This certification ensures that supervisors responsible for tank entry operations are trained and capable of ensuring safety, compliance, and risk-free execution of tasks.
Who should pursue API TES?
- Tank-cleaning supervisors
- Inspection and maintenance professionals
- Safety engineers
- Contractors handling tank repairs or modifications
- Confined-space safety professionals
API TES has become essential for industries such as oil & gas, petrochemical, storage facilities, and third-party inspection agencies where tank entry operations are frequent.
Eligibility to Appear for API TES Certification
API requires candidates to have both experience and supervisory responsibility in tank entry or confined-space operations.
Minimum Eligibility Criteria
| Education Level | Required Experience |
| Bachelor’s Degree (Engineering/Technology) | Minimum 1 year relevant supervisory experience |
| 2-Year Technical Diploma | 2 years experience, including at least 1 year in supervisory role |
| High School / Equivalent | 4 years experience, including at least 1 year supervisory |
| No formal education | 5 years experience, including at least 1 year supervisory |
Experience must be within the last 10 years and relevant to AST maintenance, cleaning, inspection, or safety management.
Certification Process (As Per 2026 Standards)
Exam Structure
- Duration: 3 hours 15 minutes
- Questions: 135 multiple-choice (120 scored + 15 pre-test)
- Mode: In-person Prometric test center or Remote proctoring
- Format: Closed-book exam
Registration & Fee
- Candidates must register and submit eligibility documents in API’s ICP portal.
- Exam fees vary depending on region and API membership category.
Scheduling
- Exams follow a rolling schedule. Candidates can choose available dates through the Prometric booking system.
- Early registration is recommended to secure availability.
Result & Certification Validity
- Results are processed and shared after evaluation.
Successful candidates receive certification valid for 3 years.
Syllabus & Training Guidance
What Does API TES Cover?
The exam topics are derived from API’s TES Body of Knowledge, including:
- Tank isolation and decommissioning procedures
- Hazard identification and risk assessment
- Ventilation and atmospheric testing requirements
- Permit-to-work and confined-space entry regulations
- Cleaning processes and tank modification safety
- Emergency response & rescue planning
- Safe recommissioning procedures
How to Prepare Training Options
Self-study is helpful but structured training for API certification exams greatly improves success rates. Many experienced professionals still need guided training to properly understand regulatory and safety frameworks.
Recommended: 1-on-1 Coaching with Gamma NDT Academy
- Personalized training based on your experience level
- Real-time doubt clearing and practical scenario learning
- Mock test support & study planning
- Guidance until certification completion
If you fail on your first attempt
- You will need to reapply for a retest within the approved timeframe
- Additional exam fees apply
- Proper coaching helps avoid delays, extra costs, and confidence loss
Certification Renewal Process
API TES certification must be renewed every three years.
Renewal guidelines:
✔ Renewal can be initiated 90 days before expiry
✔ A 90-day grace period is available after expiry (late fee applies)
✘ If you miss the grace period you must retake and pass the full exam again
Renewal ensures supervisors stay updated with current safety standards and best practices.
Job Opportunities After API TES
API TES certification unlocks high-demand roles worldwide, including:
- Tank Entry Supervisor
- Confined-Space Safety Manager
- Maintenance/Inspection Supervisor (AST operations)
- HSE Officer specializing in tank safety
- Project Supervisor on tank shutdown/recommissioning work
- Quality & Safety Consultant for inspection agencies
Industries hiring certified professionals:
- Oil & Gas refineries
- Petrochemical plants
- Storage tank facilities
- Shutdown & tank maintenance contractors
- Third-party NDT and inspection service providers
This certification significantly boosts employability, salary prospects, and international job opportunities.
Conclusion
API TES is a must-have credential for professionals responsible for tank entry safety. It enhances credibility, opens high-value job roles, and enables compliance with global safety standards.
If you want to:
✔ Build a strong career in tank inspection, maintenance or safety
✔ Work internationally in the oil & gas industry
✔ Lead confined-space operations confidently
Then API TES certification is the right path.To increase your chances of passing on the first attempt, consider specialized 1-on-1 training through Gamma NDT Academy, with complete exam preparation support.