ATEN NDT Certification for Technicians

By Greg Linkert

Over the years many AMTs have asked me, “How does someone get certified for nondestructive testing?” The path to becoming qualified and certified is spelled out in several industry standards: National Aerospace Standard 410, Air Transport Association Specification 105, and The American Society of Nondestructive Testing (ASNT) SNT-TC-1A. Additionally, the FAA has issued Advisory Circular 65-31A, titled Training, Qualification, and Certification of Nondestructive Inspection (NDI) Personnel.

Aircraft maintenance companies are required by the FAA to create nondestructive testing programs describing how they train, qualify, and certify their NDT staff. The FAA also requires employers to include in their program a description of how they recertify these individuals. Most air carriers use the Air Transport Association Specification 105 for training and certification of nondestructive testing (NDT) personnel, while many maintenance repair overhaul (MRO) organizations use the National Aerospace Standard 410. All of these standards are accepted as reference material for the creation of a nondestructive testing program.

Anyone wanting to qualify for nondestructive testing needs to clearly understand the following two terms: qualified and certification. Qualified means having the skill, training, knowledge, experience, and when applicable, the visual acuity required for personnel to properly perform to a particular level. Certification is a written statement by an employer that an individual has met the applicable requirements of the employer’s written practice. These definitions were taken from the National Aerospace Standard 410, which is controlled by The Aerospace Industries Association.

Levels of certification
Each of the previously mentioned industry standards, describe the three basic levels of certification. They are Level 1, Level 2, and Level 3.

Level 1 is the first level of qualification. A Level 1 individual should have the skills and knowledge to process parts and set up applicable equipment in accordance with written instructions provided from a Level 2 or 3.

A Level 2 individual has worked as a Level 1 for the required experience hours and passed the Level 2 qualification tests. They shall have the skills and knowledge to set up, conduct tests, interpret and evaluate signals for accept or rejection of parts, and have the ability to clearly document their inspection findings. They should be thoroughly familiar with the scope and limitations of the technique/method for which they are certified, and capable of providing training and guidance to trainees and Level 1 personnel in the method certified. Level 2 personnel are also required to be familiar with codes, standards, and other contractual documents that control the method as used by the employer.

For Level 3 certification, a Level 2 individual has three ways in which to qualify to test, all of which require the individual to have worked as a Level 2. The first way is the individual must work as a certified Level 2 for at least four years in the specific method. The second way is the individual must have spent two years in an engineering or science program from an accredited technical school, college, or university, and worked at least two years as a Level 2. The third way is for the individual to have graduated or successfully completed a three-year accredited program in engineering or science at a college or university.

Certification training and testing
When accepted for testing by ASNT the individual must first take a basic test covering general information on nondestructive testing. The methods this test covers are eddy current, ultrasound, magnetic particle, liquid penetrant, radiation, neutron radiation, leak testing, acoustic emission, vibration analysis, visual/optical, and thermo/infrared. The individual must also take a test for the specific method that certification is sought.

The American Society of Nondestructive Testing (ASNT) provides third-party certification through the ASNT Central Certification Program (ACCP). This allows an individual to gain certification without working under a specific employer nondestructive testing program. Information on this program can be found on the ASNT web site It is a very good source for study materials in nondestructive testing.

There are a number of schools where one can receive classroom training for nondestructive testing. The required classroom hours and curriculum are spelled out in the different specifications and used as a guide for these classes. Most employers use these same specification requirements for their own nondestructive testing programs. It should be mentioned for qualification in radiation some states are called Agreement States, and require additional training and certification before an individual can be certified to take X-rays.

The state of Minnesota, for example, requires an additional 160 hours of on-the-job experience and a written test administered by the Minnesota State Board of Health. This test is called the Industrial Radiographer Radiation Safety Program or IRRSP. This certification requires retesting with the state every five years for continued certification. At the end of the training classes the individual must take a written test with a minimum of 40 questions on the method for which qualification is sought. A score of 70 percent is required to pass this test.

Typical Required Classroom Training Hours for the
5 Most Common NDT Methods
      Level 2 Without
Method Level 1 Level 2 Level 1 Experience
Liquid Penetrant 16 16 32
Magnetic Particle 16 16 32
Eddy Current 40 40 80
Ultrasound 40 40 80
Radiation 40 40 80

Typical Hours of Experience Required for the 5 Most Common NDT Methods
Experience Time in Hours
  Hours of Hours of Level 1 Direct Access
  Trainee Experience Experience to Level 2 with no
  for Level 1 for Level 2 Level 1 Certification
Liquid Penetrant 130 270 400
Magnetic Particle 130 400 530
Eddy Current 400 1,200 1,600
Ultrasound 400 1,200 1,600
Radiation 400 1,200 1,600

Experience required
In addition to the classroom training requirement, the individual must also earn experience hours.

This practical experience is required and the hours required varies by method.

These hours must be acquired while working under the supervision of a qualified Level 2 or 3. Once the experience hours are reached, a test is taken for each method certification is sought. This test is a closed-book 30-question test covering the requirements and use of specifications, codes, equipment, operating procedures, and test techniques the inspector may use in the performance of their duties. This test requires a grade of 70 percent or better to pass.

When the individual has attained the required experience hours for qualification a practical test is administered. This is a hands-on test where the individual is required to demonstrate their proficiency using equipment and test samples to perform tasks typical of those required in the performance of their duties. Again, a passing grade of 70 percent is required. The practical test is administered by a Level 3 for that specific method.

Passing grades for the written general, specific, and the practical are 70 percent. But an average score of 80 percent for the three tests must be attained for certification. All certified NDT personnel are required to re-certify on a certain frequency. Level 1 and Level 2 personnel re-certify every three or five years depending on the employer’s NDT program and Level 3 personnel re-certify every five years.

More information on NDT training and certification can be found at Ridgewater College in Hutchinson, MN,, or the American Society of Nondestructive Testing,

Greg Linkert has worked in the aerospace industry for 34 years, 21 of those years he has been certified in nondestructive testing as a Level 2 and/or Level 3. He has previously sat on the ASNT Aerospace Committee for two years, was a voting member of SAE AMS Committee K for three years, and has sat on the Air Transport Association’s NDT steering committee. In 1996 Linkert was awarded the Model of Excellence and the Silver Eagle award from McDonnell Douglas for his work on the DC9 Wingbox inspection. Currently he is vice president/chief inspector of Aerotechnics Inc., an FAA certificated 145 repair station located in Minnesota providing third-party Level 2 and 3 services in nondestructive testing. He currently sits on the industry steering committee for Ridgewater College’s nondestructive testing program. More information can be found by visiting