AMERICAN SOCIETY FOR NONDESTRUCTIVE TESTING

Recommended Practice No. SNT-TC-1A • June 1975 Edition

FOREWORD

The recommended practice contained herein establishes the general framework for a
qualification and certification program. In addition, the document provides recom-
mended educational, experience, and training requirements for the different test
methods. Supplementary documents include question and answer lists which may be
used in composing examinations for nondestructive testing personnel.

Inquiries related to this recommended practice should be directed to the Chairman

of the Personnel Qualification Division, attention of the Technical Director, at the
following address:
The American Society for Nondestructive Testing
914 Chicago Avenue
Evanston, Illinois 60202

Copyright© 1975 by the American Society for Nondestructive Testing

914 Chicago Avenue, Evanston, Illinois 60202
Printed in the USA
CONTENTS

PERSONNEL QUALIFICATION AND CERTIFICATION IN

NONDESTRUCTIVE TESTING

4 Scope
4 Definitions
4 Nondestructive Test Methods
4 Levels of Qualification
5 Written Practice
5 Education, Training and Experience
6 Table 6.2.1A Recommended Training and Experience
Minimum Levels
7 Training Programs
7 Examinations
10 Certification
10 Termination
 Recommended Practice No. SNT-TC-1A

PERSONNEL QUALIFICATION AND CERTIFICATION

IN NONDESTRUCTIVE TESTING

1. SCOPE c. Certifying Agency—The employer of the per- see

sonnel being certified. 2.1(3)
1.1 It is recognized that the effectiveness of nondestruc- d. Recommended Practice—A set of guidelines to 2.1(4)
tive applications depends upon the capabilities of the assist the employer in developing uniform proce- 2.1(5)
dures for the qualification and certification of 2.1(6)
persons who are responsible for, and carry out non-
nondestructive testing personnel to satisfy his in
destructive testing (NDT). This Recommended next
Practice has been prepared to establish guidelines specific requirements.
edition
for the qualification and certification of nondestruc- e. Employer—The corporate or private entity which
tive testing personnel whose specific jobs require employs personnel for wages or salary.
appropriate knowledge of the technical principles f. Training—The program developed to impart the
underlying the nondestructive tests they perform, knowledge and skills necessary for qualification.
witness, monitor, or evaluate.
1.2 This document provides guidelines for the establish- 3. NONDESTRUCTIVE TEST METHODS
ment of a qualification and certification program.
3.1 Qualification and certification of nondestructive test-
1.3 These guidelines have been developed by the
ing personnel in accordance with this Recommended
American Society for Nondestructive Testing to aid
Practice shall be applicable to each of the following
employers in recognizing the essential factors to be
methods:
considered in qualifying employees engaged in any
of the test methods listed in Par. 3. a. Radiographic Testing (RT)
b. Magnetic Particle Testing (MT)
1.4 It is recognized that these guidelines may not be
c. Ultrasonic Testing (UT)
appropriate for certain applications. In developing
d. Liquid Penetrant Testing (PT)
his written practice as required by Par. 5, the
e. Eddy Current Testing (ET)
employer shall review the detailed recommendations
f. Neutron Radiographic Testing (NRT)
presented herein, and shall modify them as necessary
to meet his particular needs. g. Leak Testing (LT)

2. DEFINITIONS 4. LEVELS OF QUALIFICATION

2.1 Terms included in this document are defined as 4.1 There shall be three basic levels of qualification.
follows: These levels may be further subdivided by the
employer to acknowledge that additional levels of
see a. Qualification—Skill, training, and experience skills and responsibility may be necessary for specif-
2.1(1) required for personnel to properly perform the ic NDT applications.
2.1(2) duties of a specific job.
in 1980 b. Certification—Written testimony of qualification. 4.2 In the process of being qualified and certified to at

June 1975 Edition

 least NDT Level I, an individual shall be consid- ponents in accordance with the applicable quality
ered a Trainee. A Trainee shall work along with a standards.
certified individual and shall not conduct indepen-
dently any test, interpret any results of a test, or 6. EDUCATION, TRAINING AND
write a report of test results.
EXPERIENCE
6.1 Personnel considered for certification in nonde-
4.3 The three basic levels of qualification are as fol- structive testing shall have sufficient education,
lows: training and experience to ensure understanding of
the principles and procedures of those areas of
see a. NDT Level I—An NDT Level I individual shall
be qualified to properly perform specific cali- testing in which they are being considered for cer-
4.3 (1) tification.
4.3 (2) brations, specific tests, and specific evaluations
4.3 (3) according to written instructions and to record
the results. He shall receive the necessary guid- 6.2 To be considered for certification, a candidate shall see
in satisfy one of the following criteria for the applica- 6.2
next ance or supervision from a certified NDT 6.3
Level II or III individual. ble NDT level. Documented training and/or expe-
edition rience gained in positions and activities equivalent in
b. NDT Level II—An NDT Level II individual to those of level II or Level III prior to establish- next
shall be qualified to set up and calibrate equip- edition
ment of the employer’s written practice and a cer-
ment and to interpret and evaluate results with tification program in accordance with this docu-
respect to applicable codes, standards, and ment shall be considered as satisfying the criteria
specifications. He shall be thoroughly familiar
with the scope and limitations of the method of Par. 6.2.1 and 6.3.
and shall exercise assigned responsibility for on- 6.2.1NDT Levels I and II
the-job training and guidance of trainees and see
NDT Level I personnel. He shall be able to pre- Table 6.2.1A lists the recommended the minimum 6.3.1
pare written instructions, and to organize and training and experience factors to be considered by in
report nondestructive testing investigations. the employer in establishing written practices for next
qualification of Level I and Level II individuals. edition
c. NDT LEVEL III—An NDT Level III individ- The experience factor in months is based on a nor-
ual shall be capable of and responsible for estab- mal 40-hour work week (175 hours per month).
lishing techniques; interpreting code, standards
and specifications; and designating the particu- When work is performed in excess of a 40-hour
lar test method and technique to be used. He week, credit may be based on total hours. Records
shall be responsible for the complete NDT substantiating qualification shall be kept on either
operation he is qualified for and assigned to, a monthly or hourly basis.
and shall be capable of evaluating results in
terms of existing codes, standards, and specifi- 6.3 To be considered for certification as a Level III,
cations. He shall have sufficient practical back- the candidate shall satisfy one of the following edu-
ground in applicable materials, fabrication, cation and experience criteria:
and/or product technology to establish tech-
niques and to assist the design engineer in 6.3.1NDT Level III see 6.3.2 in 1980
establishing acceptance criteria where none are a. Graduate of a four-year accredited engineering see
otherwise available. It is desirable that he have or science college or university with a degree in 6.3.2(1)
general familiarity with other commonly used Engineering or Science plus one year’s experi- 6.3.2(2)
NDT methods. He shall be responsible for the ence in nondestructive testing in an assignment 6.3.2(3)
training and examination of NDT Level I and comparable to that of an NDT level II in the 6.3.2(4)
Level II personnel for certification. The actual applicable test method. in 1980
administration of training and grading of exami-
nations may be delegated to a duly selected rep- Note: if the college or university degree is issued
resentative of the level III individual and so in nondestructive testing, the one year’s experi-
recorded. ence requirement may be reduced to six months.
b. Completion with a passing grade of at least two
years of engineering or science study at an
5. WRITTEN PRACTICE accredited university, college, or technical
school plus two years’ experience as a certified
5.1 The employer shall establish a written practice for NDT Level II in the applicable test method.
the control and administration of NDT personnel c. four years’ experience as a certified NDT
training, examination, and certification. Level II in the applicable testing method.
5.2 The employer’s written practice should reflect the d. When the individual is qualified by examination,
guidelines referenced in Par. 1. the above requirements may be partially
see replaced by experience as a certified NDT
5.2 5.3 The employer’s written practice shall describe the Level II in other methods listed in Par. 3 of this
in responsibility of each level of certification for Recommended Practice as defined in the
next determining the acceptability of materials or com- employer’s written practice.
edition

June 1975 Edition

 Table 6.2.1A
RECOMMENDED TRAINING AND EXPERIENCE MINIMUM LEVELS
TRAINING (HOURS)

RT MT UT PT ET NRT

Level I Level II Level I Level II Level I Level II Level I Level II Level I Level II Level I Level II

* Completion with a passing grade

of at least 2 years of engineering
or science study at a university,
college, or technical school 12 40 8 4 24 40 4 4 8 8 12 40

** High school graduation,

diploma or its equivalent 20 40 12 8 40 40 4 8 12 8 20 40

*** Grammar school graduation,

or demonstrated proficiency, or
additional training 80 100 24 16 40 80 12 16 48 24 NA NA

WORK TIME EXPERIENCE (MONTHS)

All educational levels
as listed above 3 Mo. 9 1 3 3 9 1 2 1 9 6 24

NA = Not applicable.

Notes: Training shall be as outlined in the employer’s written practice.

For Level II certification, the experience shall consist of time at Level I. If a person is being qualified directly to Level II with no time at Level I, the required experience
shall consist of the sum of the times required for Level I and Level II as a trainee and the hours of training required for Level I and Level II in total shall apply.
Credit for experience may be gained simultaneously in two or more disciplines. The candidate must spend at least 25% of his work time on each discipline for which
experience is being claimed.

June 1975 Edition

 Table 6.2.1A (Cont’d)
RECOMMENDED TRAINING AND EXPERIENCE MINIMUM LEVELS
TRAINING (HOURS)
LEAK TESTING LEVEL I LEVEL II

BT PCMT HDLT MSLT BT PCMT HDLT MSLT

* Completion with a passing grade

of at least 2 years of engineering
or science study at a university,
college, or technical school 2 16 8 28 2 12 6 16

** High school graduation,

diploma or its equivalent 2 24 12 40 4 16 8 24

*** Grammar school graduation,

or demonstrated proficiency, or
additional training 2 96 48 NA 4 80 40 NA

WORK TIME EXPERIENCE (MONTHS)

All educational levels - Mo. 1 1/2 1 1/2 4 1/2 4 4 6
as listed above 2 Hr

NA = Not applicable.

BT = Bubble Test
PCMT = Pressure Change/Measurement Test
HDLT = Halogen Diode Leak Test
MSLT = Mass Spectrometer Leak Test

Asterisks refer to the Recommended Training Course Tables.

NOTE: Credit for experience may be gained simultaneously in two or more disciplines. The candidate must spend at least 25%
of his work time on each discipline for which experience is being claimed.

7. TRAINING PROGRAMS technical information for training courses are

appended as follows:
7.1 Personnel being considered for certification shall
Test Method Table Number
complete sufficient organized training to become Radiographic Testing II-A
thoroughly familiar with the principles and prac- Magnetic Particle Testing II-B
tices of the specified test method related to the Ultrasonic Testing II-C
level of certification desired and applicable to the Liquid Penetrant Testing II-D
practices to be used and the products to be tested. Eddy Current Testing II-E
7.2 Recommended training course outlines and sources Neutron Radiographic Testing II-F
of technical information are provided in this docu- Leak Testing II-G
Reference: ment.
7.2 7.3 The training program shall include sufficient exami- 8. EXAMINATIONS
in next nation to ensure the training material has been com-
edition 8.1 To be considered for examination, NDT personnel
prehended.
must meet the applicable requirements of the
Reference: 7.3.1 Recommended training course outlines are append- employer’s written practice.
7.2.1 ed as follows:
in 8.2 An NDT Level III individual or his selected repre- see
next Test Method Table Number
Radiographic Testing I-A sentative shall conduct and grade examinations for all
8.1
edition
Magnetic Particle Testing I-B NDT Level I and NDT Level II personnel. The 8.1.1
Ultrasonic Testing I-C 8.1.1(1)
examination to verify physical and technical qualifi-
Liquid Penetrant Testing I-D cations shall consist of the following: 8.1.1(4)
Eddy Current Testing I-E 8.1.1(5)
Neutron Radiographic Testing I-F a. Physical in
Leak Testing I-G 1. An examination shall be given to assure nat- next
ural or corrected near distance acuity in at edition
7.3.2 Recommended references to be used as sources of least one eye such that the applicant is capa-

June 1975 Edition

 ble of reading a minimum of Jaeger Number 8.3 Suggested examination questions and answers for see
2 letters at a distance of not less than 12 use in compiling appropriate general examinations 8.2
inches (30.5 cm) on a standard Jaeger test for Levels I and II have been prepared and are pre- in next
chart. The ability to perceive an Ortho- sented in the following separate Question Booklets edition
Rater minimum of 8 or similar test pattern which can be obtained from ASNT Headquarters.
shall also be acceptable. The examination
shall be administered by qualified personnel The following is a list of the booklets.
on an annual basis. Examination results
shall be kept on file for the period of certifi- Test Method Question Booklets
cation (see Par. 9.7). Radiographic Testing A
see
8.1.1 (2) 2. Individuals shall also be capable of distin- Magnetic Particle Testing B
in next guishing and differentiating contrast Ultrasonic Testing C
edition between colors used in the method for Liquid Penetrant Testing D
which qualified as demonstrated by the Eddy Current Testing E
practical examinations or test performance. Neutron Radiographic Testing F
see
8.1.1 (3) 3. Additional physical requirements should be Leak Testing G
in next considered when preparing the employer’s
edition written practice. 8.4 Until Level III questions become available, the see
Level III general examination shall consist of Level 8.1.5
see
8.1.2 b. General (written)
II questions of a number significantly greater than in next
8.1.2 (1) that used in the Level II examination. edition
8.1.2 (2) 1. The general examination shall cover the
8.1.2 (3) basic test principles relative to the applica- 8.5 The following describes the recommended examina- see
in ble method to the degree required by the tions for each NDT level for the various nondestruc- 8.3
next employer’s written practice. tive testing methods. The written examinations shall in next
edition be administered without access to reference materi- edition
2. In preparing the examination, the employer al (closed book) except that necessary data, such as
shall select or devise appropriate questions
covering the applicable method to the graphs and tables, may be provided.
degree required by the employer’s written see
practice. 8.5.1 NDT Level I 8.3
a. General Examination—The designated number 8.3.1
3. The questions and answers provided in the 8.3.1 (1)
applicable separate examination booklets are of Level I questions approved by the NDT Level
III examiner are to be answered. 8.3.1 (2)
suggested as guides for the development of in next
the general examination.
Number of edition
see Test Method Questions
8.1.3 c. Specific (Written) Radiographic Testing 40
8.1.3 (1)
8.1.3 (2) 1. The specific examination shall cover the Magnetic Particle Testing 30
in equipment, operating procedures, and test Ultrasonic Testing 40
next techniques that the applicant may encounter Liquid Penetrant Testing 30
edition in his specific assignment to the degree Eddy Current Testing 30
required by the employer’s written practice. Neutron Radiographic Testing 40
Leak Testing 15
2. The specific examination shall also cover the
specification or codes and acceptance crite- b. Specific Examination—The designated number
ria used by the employer in his nondestruc- of questions approved by the Level III examiner
tive testing procedures. are to be answered.
see
8.1.4 d. Practical
8.1.4 (1) Number of
8.1.4 (2)
1. The person considered for certification shall Test Method Questions
8.1.4 (3)
demonstrate to the satisfaction of the exam- Radiographic Testing 20
in
iner that he is familiar with and can operate Magnetic Particle Testing 20
next
the necessary test equipment and analyze Ultrasonic Testing 15
edition
the resultant information to the degree Liquid Penetrant Testing 20
required.
Eddy Current Testing 15
2. At least one selected specimen shall be test- Neutron Radiographic Testing 15
ed, and the results of the test shall be ana-
lyzed by the person considered for certifica- Leak Testing:
tion. 1. Bubble Test 10
2. Absolute Pressure Leak Test
3. The description of the specimen, the test (Pressure Change) 15
procedure, including check points, and the 3. Halogen Diode Leak Test 15
results of the examination shall be docu- 4. Mass Spectrometer
mented. Leak Test 35

June 1975 Edition

 see c. Practical Examination—Proficiency shall be c. Practical Examination—Proficiency shall be see
8.3.1(3) demonstrated in performing the applicable non- demonstrated in selecting, specifying, and writing 8.3.3(3)
in next destructive tests and limited evaluations of the specifications and/or procedures for the perfor- in next
edition results obtained on one or more samples mance of the applicable nondestructive tests edition
approved by the NDT Level III examiner. At using appropriate reference material.
least ten different checkpoints requiring an
understanding of test variables and the employ- 8.5.4 On the basis of demonstrated ability, achievement see
er’s procedural requirements should be included experience, and education, as defined in Par. 4.3.c 8.3.4
in this practical examination. and 6.3, the employer may waive examination for the in next
Level III individual. Written certification must be edition
see 8.5.2 NDT Level II provided, and evidence supporting the certification
8.3.2 shall be held on file and be made available when ver-
8.3.2 (1) a. General Examination—The designated number ification is required.
8.3.2 (2) of Level II questions approved by the
8.3.2 (3) NDT Level III examiner are to be answered. 8.6 Grading see 8.4 in next edition
in next Number of
edition Test Method Questions 8.6.1 An NDT Level III representative of the employer see
Radiographic Testing 40 shall be responsible for the conducting and grading 8.4.1
Magnetic Particle Testing 30 of examinations of all NDT Level I and Level II per- 8.4.2
Ultrasonic Testing 40 sonnel. The actual administration and grading of 8.4.3
examinations may be delegated to the duly selected 8.4.3(1)
Liquid Penetrant Testing 30 8.4.3(2)
Eddy Current Testing 30 representative of the Level III individual and so
8.4.3(3)
Neutron Radiographic Testing 30 recorded. 8.4.3(4)
Leak Testing 15 8.6.2 Recommended satisfactory percentile grades for in next
Levels I, II, and III are detailed in 8.6.4. These edition
b. Specific Examination—The designated number grades shall be a composite grade based upon the
of questions approved by the Level III examiner general, specific, and practical tests as weighted in
are to be answered.
8.6.3
Number of
Test Method Questions 8.6.3 A percentile weight factor should be applied to the
Radiographic Testing 20 percentage grades of the various examinations. The
Magnetic Particle Testing 15 percentile weight assigned any particular examina-
Ultrasonic Testing 20 tion should be within the ranges listed below and
Liquid Penetrant Testing 15 should be established in accordance with the princi-
Eddy Current Testing 15 ples outlined in Par. 1.4. The total of the three per-
Neutron Radiographic Testing 15 centile weights shall equal 1.0.
Leak Testing: a. NDT Level I Examination Grades
1. Bubble Test 10 1. General — 0.2 to 0.6
2. Absolute Pressure Leak 2. Specific — 0.1 to 0.5
Test (Pressure change) 15 3. Practical — 0.3 to 0.7
3. Halogen Diode Leak Test 15 b. NDT Level II Examination Grades
4. Mass Spectrometer Leak Test 50
1. General — 0.3 to 0.7
c. Practical Examination—Proficiency shall be 2. Specific — 0.2 to 0.6
demonstrated in selecting and performing the 3. Practical — 0.1 to 0.5
applicable nondestructive tests and evaluating the c. NDT Level III Examination Grades
results obtained on one or more samples 1. General — 0.4 to 0.6
approved by the NDT Level III examiner. At 2. Specific-Practical — 0.4 to 0.6
least ten different checkpoints requiring an d. The composite grade (Gc) is determined as fol-
understanding of test variables and the employ- lows:
er’s procedural requirements should be included
in this practical examination. Gc = (Gg ´ Wg) + (Gs ´ Ws) + (Gp ´ Wp)
Where Gc = Composite grade
Gg = Actual grade from general examina-
see 8.5.3 NDT Level III
tion in percent
8.3.3
Wg = Percentile weight of general examina-
8.3.3 (1) a. General Examination—Thirty questions devised tion
8.3.3 (2) by the examiner for the appropriate method, plus Gs = Actual grade from specific examina-
in next 30 questions from the NDT Level II questions for tion in percent
edition other applicable NDT methods, are to be Ws = Percentile weight of specific exami-
answered. nation
b. Specific Examination—Appropriate questions Gp = Actual grade from practical examina-
shall be chosen to demonstrate a knowledge of tion in percent
test variables and the employer’s procedural Wp = Percentile weight of practical exami-
requirements. nation

June 1975 Edition

 e. Example: of the certified individuals and copies of written
1. Test results obtained for Level I examina- practices as required by Par. 5.
tion =
General (Gg)= 87% 9.6.1 The personnel records of the certified individuals
Specific (Gs) = 93% should include as a minimum the following:
Practical (Gp)= 90%
a. Name of certified individual. see
2. Percentile weight assigned for each exami-
nation = b. Level of certification and test method. 9.6.1(1)
General (Wg) = 0.3 c. Educational background and experience of certi- 9.6.1(2)
Specific (Ws) = 0.2 fied individuals. 9.6.1(3)
Practical (Wp) = 0.5 d. Statement indicating satisfactory completion of 9.6.1(4)
1.0 9.6.1(5)
training in accordance with the employer’s writ-
in next
3. Then: Gc = (87 ´ 0.3) + (93 ´ 0.2) + ten procedure. edition
(90 ´ 0.5) e. Results of the physical examination prescribed in
Gc = 26.1 + 18.6 + 45 Par. 8.2.a.
Gc = 89.7% f. Copies of current examinations and of grades for see
all previous examinations and descriptions of 9.6.1(6)
see 8.6.4 When an examination is administered for NDT practical test objects. in next
8.4.4 Level I or Level II qualification, a composite grade g. Percentile weights assigned to each examination if edition
in of 80% or greater is required for qualification. In examinations were employed for qualification.
next addition, each grade for the general, specific, and
edition h. Composite grade if examinations were employed. see
practical examinations shall be 70% or greater.
i. Date of certification and/or recertification and the 9.6.1(8)
Test objects shall be used in the practical examina-
dates of hire or assignment to NDT. 9.6.1(9)
tion, and at least 90% of the known indications 9.6.1(10)
should be found. For NDT Level III, a composite j. Signature of certifying agency representative.
in next
grade of 90% is required, and no grade shall be less edition
than 80%. 9.7 Re-Certification
see 8.7 Re-examination 9.7.1 All levels of NDT personnel should be re-certified at see
8.5 least once every three years in accordance with one 9.7.1
in a. Those failing to attain the required grades must of the following criteria as determined by the
wait at least 30 days or show evidence of having 9.7.1(1)
next employer: 9.7.1(2)
edition received suitable additional training as deter- a. Evidence of continuing satisfactory performance.
mined by the employer before re-examination. in next
b. Re-examination in accordance with Par. 8 and 9. edition
9.7.2 NDT personnel may be re-examined any time at the
9. CERTIFICATION discretion of the employer and have their certifica-
9.1 Certification of all levels of NDT personnel is the tion extended or revoked.
responsibility of the employer. 9.7.3 The employer shall in his written practice establish
rules covering the duration of interrupted services
9.2 Each employer shall establish written practices cov- which will require re-examination and recertifica-
ering all phases of certification including training as tion.
specified in Par. 5.
9.3 Certification of NDT personnel shall be based on 10.TERMINATION
demonstration of satisfactory qualification as deter-
mined by procedures outlined in Par. 6, 7, and 8 as 10.1 All certification shall be automatically terminated
modified by the employer’s written practices. when an employee leaves the employer where he
9.4 At the option of the employer, an outside agency may had been certified.
be engaged to provide NDT Level III services. In 10.2 A terminated Level I or II employee may be recerti-
such instances, the responsibility of certification fied to his former NDT level by a new employer
must be retained by the employer utilizing outside based on examination as described in Par. 8.2 pro-
services. vided all of the following conditions are met to the
9.5 The purchaser of outside certification services is new employer’s satisfaction:
responsible for auditing the agency providing such a. The employee has proof of prior certification. see
services to assure that training, examination, and cer- 10.2(1)
b. The employee was working in the capacity to
tification are in accordance with this document. He which he had been certified within six months of 10.2(2)
must maintain a written record of his audit. his termination. 10.2(3)
in next
9.6 Certification records shall be maintained on file by c. The employee is being re-certified within six edition
the employer and should contain personnel records months of his termination.

June 1975 Edition

Recommended Practice

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