This article describes what it takes to become an ASNT certified NDT/NDE inspector. Certification in one
process does not qualify an individual for another process. Full re-certification is required
every three years for each process. Depending upon age, an annual vision test may also be required.
Nondestructive testing personnel are often certified by their employer or other
agency to meet specific qualification levels. Certification is a process of providing written
proof that an individual is qualified to do a certain inspection task. The
qualifications of an individual are based on education, level of
training, work experience, and the ability to pass a vision test.
In the field of NDT/NDE, certification is important because NDT/NDE
personnel are often making critical judgments that can have safety
and/or significant financial consequences if not performed properly. NDT/NDE personnel must have
a tremendous amount of confidence in the results of their work. Since many
of the NDT/NDE methods do not produce a permanent record of the inspection results,
certification presents objective evidence of the knowledge and skill
level of the person performing an inspection.
The procedure used to assure that NDT/NDE personnel
possess the qualifications necessary to do competent work includes:
Certification can be obtained in number of NDT/NDE methods,
which are listed in the table below.
NDT/NDE personnel are generally certified to several different
levels of competence within each of the NDT/NDE methods they are working.
The levels are Level I, Level I Special, Level II, and Level III.
Level I technicians are only qualified to perform
specific calibrations and tests, and acceptance or rejection determinations
allow little or no deviation from the procedure. Level I technicians
are under close supervision and direction of a higher level tester.
The level I position is not the trainee level, but the first level
a trainee reaches upon demonstrating ability in specific tests.
Level I Special personnel are limited even more in what they can
do. They are usually trained to a specific procedure and can perform
only certain types of inspections on a certain set of components.
Level II technicians are able to set up and calibrate
equipment, conduct the inspection according to procedures, interpret,
evaluate and document results in all the testing method(s) utilized
by the certificate holder. The technician can provide on the job
training for Level I and Level I Specials and act as a supervisor.
The technician can also organize and document the results of the
inspection. They must be familiar with all applicable codes, standards,
inspection procedures, and other documents that control the NDT/NDE method being utilized.
Level III technicians are capable of establishing inspection
techniques and procedures; interpreting codes, standards, and
specifications; and designating the particular nondestructive
testing methods, techniques, and procedures to be used. They must
also have knowledge of materials, fabrication, and product technology.
Level III technicians are responsible for training and examining
Level I and Level II's. Usually level III technicians are in administration,
supervision, or management positions, or are owners of a testing
laboratory. Some Level III technicians also become consultants.
Certification Requirements
There are a number of organizations that have produced
documents that recommended or specify the minimum qualifications
for certification. The following is a partial list of documents
pertaining to the certification of NDT/NDE personnel in the USA.
- ASNT-SNT-TC-1A, The American Society for Nondestructive Testing,
Recommended Practice, Personnel Qualification and Certification
in Nondestructive Testing.
- ATA-105 Aviation Transport Association, Guidelines for Training
and Qualifying Personnel in Nondestructive Testing Methods.
- AIA-NAS-410, Aerospace Industries Association, National Aerospace
Standard, NAS Certification and Qualification of Nondestructive
Test Personnel.
- ISO 9712, International Organization for Standards, Nondestructive
testing -- Qualification and certification of personnel.
The education and work experience requirements for the various
specification are common or similar. Typical requirements are summarized
in the table below for qualification levels I and II. Please consult
the certification documents to assure that information is correct
for your situation.
| Examination Method |
Level |
Required Hours of NDT Training
|
Minimum hours of work experience
in a method |
Permitted time frame to obtain
required work experience in a method (In Months) |
For those with high school diploma
or equivalent
|
For those with at least 2 years of
engineering or science study at a college or technical school
|
| Acoustic Emission |
I
|
40
|
32
|
210
|
1.5-9
|
|
II
|
40
|
40
|
630
|
4.5-27
|
| Eddy Current |
I
|
40
|
24
|
210
|
1.5-9
|
|
II
|
40
|
40
|
630
|
4.5-27
|
| Liquid Penetrant |
I
|
4
|
4
|
70
|
0.5-3
|
|
II
|
8
|
4
|
140
|
1-6
|
| Magnetic Particle |
I
|
12
|
8
|
70
|
0.5-3
|
|
II
|
8
|
4
|
210
|
1.5-9
|
| Neutron Radiography |
I
|
28
|
20
|
420
|
3-18
|
|
II
|
40
|
40
|
1680
|
12-72
|
| Radiography |
I
|
40
|
30
|
210
|
1.5-9
|
|
II
|
40
|
35
|
630
|
4.5-27
|
| Thermal/Infrared |
I
|
32
|
30
|
210
|
1.5-9
|
|
II
|
34
|
32
|
1260
|
9-27
|
| Ultrasonics |
I
|
40
|
30
|
210
|
1.5-9
|
|
II
|
40
|
40
|
840
|
4.5-27
|
| Vibration Analysis |
I
|
24
|
24
|
420
|
2-18
|
|
II
|
72
|
48
|
1680
|
12-72
|
| Visual |
I
|
8
|
4
|
70
|
0.5-3
|
|
II
|
16
|
8
|
140
|
1-6
|
NDT training can be obtained at colleges, vocational-technical
schools, the Armed Forces, commercial training companies and through
individual company training departments.
To be considered for certification as a Level III
an individual must:
- Have graduated from a university or college with a degree
in engineering or science, and have at least one year of experience
comparable to that of a Level II in the applicable NDT method(s). or
- Have completed with passing grades at least two years of engineering
or science study at a university, college or technical school
and have two years of experience comparable to that of a Level
II in the applicable NDT method(s). or
- Have four years of experience comparable to that of a Level
II in the applicable NDT method(s).
Certification Examinations
Once the education, training and work experience requirements
have been met and documented, certification examinations must be
taken. The examination process is three part and includes several exams.
For certification to Levels I and II a general, a specific, and a practical,
exam must be completed with a passing grade of 70 percent for each
exam and a composite grade of 80 percent (determined by averaging
the results of the three exams). The general exam contains questions that are fairly specific to
the particular inspection process. The specific exam contains interpretation questions that are
specific to both the inspection process and one or more codes that would cover that process.
The practical exam is a "hands on" test using a test specimen with known defects. The questions on the practical
test address accept or reject criteria for the specimen to one or more codes using an inspection procedure for
that particular inspection process. More on Exams
below.
The Level III exam process includes
completion of a basic, a method, and a specific examination with a passing grade of 70 percent for each exam and
a composite grade of 80 percent. Level I and II exams must be administered
by an NDT level III and this is usually done within companies that provide either in-house or public inspection services.
Level I, II and III exams can also be taken through a central agency
such as ASNT. Central certifications provides technicians with documentation
of qualification that is recognized nationally and in some cases internationally.
Visual Examination
It is important that NDT personnel have good near
visual acuity and color vision. Therefore, an eye test must be taken
to insure that natural or corrected near distance acuity is acceptable.
Depending on which specification the company uses for certification,
an individual must be able to read a Jaeger Number 1 or 2 (or equivalent)
type and size letter at the designated distance.
Determining contrast of color(especially shades of red) or shades of gray is also generally
required. Color blindness can prohibit an individual from qualifying for
certain inspection processes.
Level I and II General Examinations
A general examination is a written test
which covers the general principles of a particular NDT method.
The test will range from a minimum of 20 to 40 questions. There
are practice general exams with answers available in a convenient Ebook format for
six of the most widely used inspection methods. These are: ET, MT, PT, RT, UT, and VT.
These can be purchased for a nominal price.
Level I and II Specific Examinations
A specific examination is a test
which is related to specifications, equipment, techniques and procedures
which the employer uses and requires a specific level of expertise
from their personnel. This examination should also cover the codes
and procedures used by the employer.
Practical Examination (for
Level I and II)
A practical exam tests an individuals ability
to operate the necessary equipment, record and analyze the results
and accept or reject the part under inspection. A part is selected
and the individual is expected to find indications and accept
or reject the part to a specific code.
Basic Examination (for
Level III)
Covers questions concerning the following:
qualification and certification
materials, fabrication and product technology
general NDT methods
Method
Examination (for Level III)
Covers questions concerning
the following:
the fundamentals and principles for the NDT method covered
by the exam
the application and establishment of techniques and procedures
the capability for interpreting codes, standards and specifications
relating to the method covered by the exam
Specific
Examination (for Level III)
Covers questions concerning the following:
the specifications, equipment, techniques and procedures
applicable to specific products
methods employed to inspect the products
written practices
The above are the general requirements for inspector certification to
ASNT-SNT-TC-1A that is the accepted certification associated with the ASME
(American Society of Mechanical Engineers) code. The AWS (American Welding
Society) and the API (American Petroleum Institute) code organizations
have similar and also some totally different certification requirements
for working with their respective codes.
AWS has specific requirements for visual inspection under its codes. Visual
inspectors certified under ASNT-SNT-TC-1A are not certified to visually inspect
any work performed under AWS codes. AWS does accept inspection certifications
for most NDT/NDE personel that certified under ASNT-SNT-TC-1A for other inspection
methods such as MT, PT, RT, and UT provided that the inspection procedures in the
AWS codes are followed.
API will accept visual and NDT/NDE certifications from both AWS and ASME for certain
work under their codes. Other specific inspection types require certification under API
code requirements for items such as petroleum storage tanks.
Inspection requirements can be confusing without having access to the code books
from each respective organization. AWS inspection requirements are addressed in AWS
code D1.1. ASME inspection requirements are addressed in ASME Section V. API Standard
620 sets the requirements for an inspector under their codes.