Whether your building project is residential, commercial or industrial, safety is paramount. Nondestructive testing, or NDT, plays an essential role in making sure your completed structure is not only safe for its intended use and the people who will be around it, but that it will stand the test of time.
If you’ve ever seen news headlines about a building toppling over, a bridge collapsing or a dam failing, you’ve seen firsthand the destruction of life and property that can result from structures whose integrity has not been properly checked, not to mention the reputational and monetary damage suffered by the firm responsible.
Thus, it’s in your best interest and that of the general public to use the best NDT technicians in the business for your build.
What is a nondestructive testing technician?
Nondestructive testing uses a variety of techniques to examine the integrity of a structure or product with a particular attention to quality and safety. An NDT technician is the professional who performs these tests.
In addition to planning, executing and overseeing the tests themselves, they may compile reports and present their findings to the appropriate stakeholders.
The word ‘nondestructive’ in NDT is important because it means the tests can be completed without any meaningful impact to the structure being examined.
As you can imagine, this is a very helpful asset of NDT when you’re looking to keep the work moving on your build.
So what exactly does an NDT technician test? They’re looking for what are called discontinuities–flaws or imperfections according to a given specification that may or may not be indicative of an underlying issue.
A discontinuity might be a crack in a block of concrete, for example, or a section of pipe that’s corroded to the point of defectiveness. These are things that, at their worst, could cause the structure to fail and threaten human life. At the very least, they call for a closer look.
What should you look for in a good NDT technician?
First and foremost, a good NDT technician should be certified. Look for certification from a recognized organization like the American Society for Nondestructive Testing (ASNT), the foremost technical society for nondestructive testing in the U.S. Certification helps verify the inspector’s education and experience with the appropriate standards and techniques they’ll use when examining your build.
Next, look for an NDT technician with a strong attention to detail. This is not the time or place to work with someone who takes a casual approach to their work.
Depending on your level of certification, your NDT technician is going to be conducting highly important tests, analyzing their results and helping you understand what those results mean, so you want someone who’s thorough and is going to leave no stone unturned.
Finally, look for a strong communicator. Your technician should be able to easily speak and write in plain terms about their work and its implications.
Though they deal in technical subject matter, they need to be able to convey it in a way that owners, developers and other onsite staff can understand, without things getting lost in translation.
A good time to get a feel for a technician’s communication skills is during the interview process; ask your prospective technician how they’d explain what they do to a friend who has no knowledge of nondestructive testing and see how well you can follow their response.
Keep the demands of your build in mind
No two builds are alike, so it’s important to consider what makes yours unique when hiring NDT technicians.
Consider the primary materials used on your job site. Does your build involve lots of metal, like pipelines?
Then you might want an NDT technician who specializes in ultrasonic testing. Is your build largely reinforced concrete, like an office building? You’ll probably want someone who’s well-versed in penetration testing.
In addition to the materials used in your build, you’ll want to consider the stage it’s in and how much access you have. For example, can you get inside, on top of, and underneath the structure, or will testing need to be done com[pletely from the outside? Are you able to apply testing materials like liquid penetrants to the structure, or will your technician be examining it from a distance?
A knowledgeable NDT technician should be able to speak in detail about the specifics of your build and how they would approach your particular job to get the most useful and reliable results.
Finally, you’ll need to consider the practical factors of your build like the budget and timeline. In a perfect world where money was no object, you’d conduct every test imaginable to find every possible discontinuity. Unfortunately, most developers wouldn’t be too pleased with that approach.
Instead, you’ll need to consult specifications and standards, as well as rely on an NDT technician who can help you narrow down the most effective testing methods and approach to suit the financial and timing demands of your build.
Some tests can be done more inexpensiv\vely than others but don’t produce as thorough results, while others go deeper but cost more or take more time. So, you’ll need to weigh these factors when choosing the right NDT technician to work with.
Look out for passive candidates
The tough thing about hiring NDT technicians is that the best candidates probably aren’t going to come walking through your door or even send you their resume–they’re already busily employed on other job sites.
These are what’s known as passive candidates–people who aren’t actively looking for a job because they’re currently employed. Passive candidates make up an estimated 73% of your candidate pool.
Passive candidates are tricky to reach, but they’re often some of the highest performers and are known for being highly engaged in their work, so there’s a strong case for making efforts to connect with them.
Rather than waiting for them to come to you, you’ll need to take proactive steps to let them know you’re looking for NDT technicians like them.
Look for a mix of experience and certifications
We touched briefly on NDT technician certifications above, but simply holding one certification might not be sufficient. Not all levels of certification, for example, are considered qualified to supervise other technicians.
To understand whether a candidate’s credentials will actually translate into the expertise they need for your build, it’s helpful to have an understanding of the different certification levels and what they entail. Here’s a basic breakdown.
NDT LEVEL I
A technician with level I certification can perform specific calibrations of instruments, perform specific nondestructive tests, and record the results of same. A level I technician needs to work under the supervision of a level II or level III technician.
Essentially, they can carry out testing with very specific instructions, but they can’t help you formulate the approach or make judgement calls on the appropriate testing techniques.
NDT LEVEL II
A level II technician can set up and calibrate testing equipment, conduct tests, and evaluate the results in accordance with the applicable codes.
They should be able to advise you on the limitations of a particular type of testing, like whether a certain NDT technique is sufficient for the type of material you’re dealing with. Level II technicians can train and supervise trainees and level I personnel.
NDT LEVEL III
If you’re developing an NDT plan for your build from scratch, a level III NDT technician is who you’re going to want leading the charge. They’re certified to develop, qualify and approve testing procedures, establish the right testing techniques for your build, and interpret the relevant codes and standards to make sure you’re in compliance.
They should be well-versed in the materials and fabrication you’re using on your job site and can supervise all levels of technicians beneath them in carrying out the testing plan.