ISO 9712 is a certification standard, not a recommended practice. A third-party certification body — not the employer — decides whether a candidate is admitted to examination, so the training and experience minima are hard entry gates rather than guidance. A candidate arrives at the examination centre with a training certificate stating the hours and a signed experience statement from the employer; if either falls short of the table, the candidate is not examined.

Training is organised instruction to a syllabus, normally ISO/TS 25107 for the practical content. Industrial experience is measured in months of documented work under qualified supervision, on a nominal 40-hour week or the legal working week of the country. Someone working half-time on the method accumulates half a month of credit per calendar month, so the calendar time to eligibility stretches accordingly. Experience gained before training may be counted, but experience gained while under examination-only supervision generally is not.

Levels are cumulative and the table assumes the candidate already holds the level below. A candidate going straight to Level 2 without Level 1, or straight to Level 3, must satisfy the sum of the durations for all the levels concerned — no reduction is permitted for that route. Working the other way, the training duration alone may be reduced where the candidate holds relevant higher education or is already certified in other methods, but only with the agreement of the certification body; experience months are never reduced on those grounds.

Certification is valid for five years. Renewal at five years requires a current vision test and evidence of continuous satisfactory work without significant interruption; recertification at ten years additionally requires a practical examination, or acceptance under a structured credit system where the certification body operates one. A significant interruption in the method restarts the argument about competence and normally means re-examination.

Worked example

NDT method	1
Level sought	2
Route	1
Agreed training reduction	0 %
Training hours already completed	40 h
Experience already credited	4
NDT hours worked per week	40 h
Minimum training required	120 h
Minimum industrial experience	12
Calendar months at your working pattern	12
Training shortfall	80 h
Experience shortfall	8

UT Level 2 by direct entry, so Level 1 and Level 2 rows are summed. Training 40 + 80 = 120 h; the candidate holds 40 h, so 80 h short. Experience 3 + 9 = 12 months; at a full 40 h week the calendar time is 12 × 40/40 = 12 months, and with 4 months credited the shortfall is 8 months.