RT Radiography Testing Explained in English
Citation information
By Amado Garcia
www.Aqualified.com
June 18, 2010
Please note this is a free RT Radiography Testing X-ray review for a non-technical look at the method in reference to nondestructive testing. Some terms in this article might not be industry appropriate and other things are simply skipped. For a true radiography course per SNT-TC-1A or NAS-410 or CP-189 contact us and schedule your training.
RT Radiography is also known as XT X-ray testing, SRT Source Radiography, Radiologic Testing, Gamma Radiography and Neutron Radiography Testing. All of these are part of the radiographic family and are dangerous, expensive and popular. The ability to be able to see inside of things and provide a permanent historical image has made it one of the most popular NDT inspection methods.
So what is Radiography or X-ray? The text book answer is: the use of X-rays or nuclear radiation, or both, to detect discontinuities in material, and to present their images on a recording medium. My definition is: An energy that is capable of penetrating a physical object and creating an image on film or a digital plate. Imagine a light that could penetrate your entire body without you feeling heat, a tingle or any type of sensation. Yet it can cause the same damage as if though you were severely sunburned completely throughout your body. That is the danger of radiation and why it is such a controlled process.
You should not be alarmed when encountering properly trained professionals designated by a radiographers card (a license to shoot x-rays). The average field industrial radiographer has to go through a 40 hour Radiation Safety Class to ensure they can operate a radiation device safely and that the general public is safe around them. This is augmented by another 40 hour class to achieve an RT Level I Inspector designation and another 40 hour class to achieve an RT Level II qualification. In order for the technician to become a true NDT RT Level II certified inspector, they will also need an excess of 800 hours On the job training (OJT) before they can be considered a certified level II radiography NDT inspector.
Hopefully you have seen an X-ray at a doctor’s office. Those X-rays are usually at a much lower intensity than those used for industrial radiography. Industrial X-rays are used to penetrate metals, composites, concrete, and any other material someone desires to look inside of. The industrial image is usually more sensitive (more defined and clearer) than a medical X-ray image. Typical indications sought with radiography include porosity, shrinkage, lack of penetration, lack of fusion, cracks, corrosion, water entrapment, foreign objects and any other indication which would cause a density variation within the material. A density variation is represented on the X-ray film by darker and lighter areas which directly correlate to thinner and thicker areas of the same material or dissimilar materials of the same thickness and overall dimension which weigh differently such as steel and aluminum.
So what is Radiography or X-ray? The text book answer is: the use of X-rays or nuclear radiation, or both, to detect discontinuities in material, and to present their images on a recording medium. My definition is: An energy that is capable of penetrating a physical object and creating an image on film or a digital plate. Imagine a light that could penetrate your entire body without you feeling heat, a tingle or any type of sensation. Yet it can cause the same damage as if though you were severely sunburned completely throughout your body. That is the danger of radiation and why it is such a controlled process.
You should not be alarmed when encountering properly trained professionals designated by a radiographers card (a license to shoot x-rays). The average field industrial radiographer has to go through a 40 hour Radiation Safety Class to ensure they can operate a radiation device safely and that the general public is safe around them. This is augmented by another 40 hour class to achieve an RT Level I Inspector designation and another 40 hour class to achieve an RT Level II qualification. In order for the technician to become a true NDT RT Level II certified inspector, they will also need an excess of 800 hours On the job training (OJT) before they can be considered a certified level II radiography NDT inspector.
Hopefully you have seen an X-ray at a doctor’s office. Those X-rays are usually at a much lower intensity than those used for industrial radiography. Industrial X-rays are used to penetrate metals, composites, concrete, and any other material someone desires to look inside of. The industrial image is usually more sensitive (more defined and clearer) than a medical X-ray image. Typical indications sought with radiography include porosity, shrinkage, lack of penetration, lack of fusion, cracks, corrosion, water entrapment, foreign objects and any other indication which would cause a density variation within the material. A density variation is represented on the X-ray film by darker and lighter areas which directly correlate to thinner and thicker areas of the same material or dissimilar materials of the same thickness and overall dimension which weigh differently such as steel and aluminum.