The standard subdivides non-destructive testing executives on three levels and defines the skills that can be summarized as follows:

Level I: Execution of control

A Level I certified person has demonstrated competence to perform non-destructive testing in accordance with written instructions under the supervision of certified staff at Level II or Level III.
With the purpose and skills defined in the certificate, Level 1 staff may be authorized by the employer to carry out the following operations in accordance with the PND instructions:

• set the NDT (Non Destructive Testing) equipment;
• test;
• result and classify test results in accordance with NDT instruction criteria;
• refer the result;

Level II: Interpretation of results and assessment of compliance with specifications, also Level II gives I level instruction statements that can only work with Level II statements.

A certified person Level II has demonstrated competence to perform non-destructive testing in accordance with a NDT procedure. With the purpose and skills defined in the certificate, Level II staff may be authorized by the employer to:

• select the NDT technique for the method used;
• define limitations in the application of the NDT method;
• translate NDT codes, standards, specifications and procedures in NDT instructions appropriate to the actual test conditions;
• set up and verify the CND tool settings;
• perform and monitor the NDT test;
• interpret and evaluate results in accordance with standards, codes, specifications, or procedures applied;
• implement and supervise all Level II or Level I activities;
• provide guidance to Level II or Level I staff; refer the result;

Level III: organization of the system of non-destructive checks, drafting of specifications and personnel training.

The subdivision in the three tiers applies to any method of non-destructive testing.

The UNI EN ISO 9712 standard also defines the procedures for certification in the three levels. Direct Access to Level II requires the sum of the hours scheduled for Level I and Level II

Table – minimum hours of training for Level I and Level II

*Note for RT, training hours do not include radiation safety training

Table– Industrial experience

Non-destructive testing of surface and volumetric properties applicable to welds is defined by UNI EN ISO 17635.