Why NDT Certification Matters
Non-destructive testing is a safety-critical activity. The interpretation of inspection results directly affects decisions about asset integrity and public safety.
The industry relies on certification schemes that verify an individual has the required training, experience, and examination performance to perform inspections competently.
Understanding Certification Levels
Most NDT certification programs use a three-level structure:
Level I - Technician
- Performs inspections under supervision
- Sets up equipment per written procedure
- Records and classifies results per written criteria
Level II - Practitioner
- Sets up and calibrates equipment
- Interprets and evaluates results per codes
- Prepares written inspection procedures
- Supervises and trains Level I personnel
Level III - Expert
- Develops, qualifies, and approves procedures
- Interprets codes, standards, and specifications
- Administers certification programs
- Provides technical guidance and training
Major Certification Programs
ASNT SNT-TC-1A (Employer-Based)
The most widely used scheme in North America. Employer certifies their own personnel per written practice. Flexible but not portable between employers.
ASNT Central Certification (ACCP)
ASNT's portable, third-party certification. Valid 5 years with recertification.
ISO 9712 / EN ISO 9712
International standard for NDT personnel qualification. Third-party certification with global recognition.
PCN (Personnel Certification in NDT)
UK-based certification administered by BINDT. Follows ISO 9712, widely recognized internationally.
How to Get Certified
- Choose your methods: Common starting points are UT Level I or MT/PT Level II
- Complete training: 40-80 hours classroom training per method/level
- Gain experience: Work under certified supervision
- Pass examinations: General, specific, and practical exams
- Maintain certification: Continue working, recertify on schedule
Frequently Asked Questions
What is ASNT certification?
ASNT (American Society for Nondestructive Testing) publishes SNT-TC-1A, the recommended practice under which most US employers certify NDT personnel as Level I, II or III in each method. ASNT also runs the central ACCP and the ASNT NDT Level III certification examinations.
What is the difference between SNT-TC-1A and ISO 9712?
SNT-TC-1A is an employer-based recommended practice: the employer certifies personnel against a written practice. ISO 9712 is a third-party (central) certification scheme where an accredited body certifies the individual, so the certification is portable between employers. PCN (UK) and many European schemes follow the ISO 9712 model.
What is PCN certification?
PCN (Personnel Certification in Non-Destructive Testing), administered by BINDT in the UK, is a third-party certification scheme compliant with ISO 9712. It is widely recognised internationally, especially in oil and gas.
How long does it take to become a Level II inspector?
It depends on method and prior education, but SNT-TC-1A and ISO 9712 set minimum classroom training hours plus documented on-the-job experience for each method (for example, Level II UT commonly requires substantial training hours plus several months of experience). The employer or certification body verifies the hours and a passing exam.
Which NDT certification is best?
There is no single best — it depends on where and for whom you work. ASNT SNT-TC-1A dominates the US; ISO 9712 / PCN are preferred internationally and for portability; NAS 410 governs aerospace. Many inspectors hold more than one to maximise marketability.
Sources
- ASNT — Certification (SNT-TC-1A, ACCP, NDT Level III)
- ISO 9712 — Qualification and certification of NDT personnel
- BINDT — PCN certification
- NAS 410 / Nadcap — aerospace NDT qualification
Last reviewed: June 2026.
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