The American Society for Nondestructive
Testing (ASNT) Recommended Practice
No. SNT-TC-1A is an "In
-house" employer based
training, qualification and
This document established levels
of qualification based upon
a combination of education,
training, experience, and qualification
examinations. The basic levels
begin with NDT Level I primarily
used as an operator technician.
NDT Level II, the next level
requires more training and experience,
but permits more independent
activity including accepting
and rejecting test objects.
The NDT Level III requires experience
comparable to an NDT Level II.
The number of years depends
upon the candidate's formal
SNT-TC-1A requires an internal
company procedure that details
how employees are trained, qualified
and certified to perform NDT
functions for the company.
The Written Practice should
provide descriptions of:
NDT methods used such as Laser
Shearography (LR), Radiography
(RT) , Ultrasonic (UT) etc.
of personnel qualification.
LEVEL I - qualified to
perform specific calibrations,
specific examinations and specific
evaluations (with specific written
LEVEL II - qualified
to set-up and calibrate equipment
and to interpret and evaluate
results with respect to codes,
standards, and specifications.
Must be able to prepare written
instructions, qualified to provide
on-the-job training and guidance
of trainees and report examination
LEVEL III - must be capable
and responsible for establishing
techniques, interpreting codes,
and designating the test method
and technique to be used, and
capable of training and examining
NDT Level I and II personnel
for certification. Must have
a practical background in the
technology and be familiar with
other commonly used methods
/ re-certification requirements
and interruption intervals.
Typically, Level I and Level
II personnel are recertified
at three (3) year intervals
and Level III personnel are
recertified at five (5) year
intervals; however, interruption
intervals of inactivity for
suspension of certification
should be addressed.
Personnel should achieve the
minimum experience level recommended
which will vary for each particular
NDT method. This initial experience
may be in recorded in months
or hours. This option should
be determined by the employer
and described in the employer's
NDT Level I/II examinations
eye exam for near vision acuity
and color contrast discrimination.
examination to demonstrate the
candidate's knowledge of the
basic principles and fundamentals
of the method.
evaluation of practical work
performance is provided by a
"Practical Test" portion.
Certification is a written statement
of qualification. Using employer-based
programs such as SNT-TC-1A requires
National Aerospace Standard,
many years, aerospace and defense
related military or government
contracts required NDT personnel
qualifications in accordance
with MIL-STD-410E. It was replaced
in the 1990's by NAS 410.
Many companies are currently
using the January, 1996 revision
1; however, Revision 2 was published
in February, 2003. Revision
2 changed the re-certification
period for Level I and II from
3 years to 5 years.