Inspection Certification

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:

Classroom training to gain the necessary knowledge
Practical experience under the guidance of an experienced inspector
Three separate qualification examinations to demonstrate that competancy has been achieved
Written certification to document successful demonstration of competency.
NDT/NDE Methods

Certification can be obtained in number of NDT/NDE methods, which are listed in the table below.
Acoustic Emission Testing AE
Eddy Current Testing ET
Leak Testing LT
Liquid Penetrant Testing PT
Magnetic Particle Testing MT
Neutron Radiographic Testing NRT
Radiographic Testing RT
Thermal/Infrared Testing TIR
Ultrasonic Testing UT
Vibration Analysis Testing VA
Visual Testing VT


NDT/NDE Certification Levels

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.