Home - Education Resources - NDT Course Material - Radiography - Real-Time




Real-time radiography (RTR), or real-time radioscopy, is a nondestructive test (NDT) method whereby an image is produced electronically rather than on film so that very little lag time occurs between the item being exposed to radiation and the resulting image. In most instances, the electronic image that is viewed, results from the radiation passing through the object being inspected and interacting with a screen of material that fluoresces or gives off light when the interaction occurs. The fluorescent elements of the screen form the image much as the grains of silver form the image in film radiography. The image formed is a “positive image” since brighter areas on the image indicate where higher levels of transmitted radiation reached the screen. This image is the opposite of the negative image produced in film radiography. In other words, with RTR, the lighter, brighter areas represent thinner sections or less dense sections of the test object.

Real-time radiography is a well-established method of NDT having applications in automotive, aerospace, pressure vessel, electronic, and munition industries, among others. The use of RTR is increasing due to a reduction in the cost of the equipment and resolution of issues such as the protecting and storing digital images. Since RTR is being used increasingly more, these educational materials were developed by the North Central Collaboration for NDT Education (NCCE) to introduce RTR to NDT technician students. NCCE is a collaborative effort between Northeast Iowa Community College (Peosta, IA) Cowley County Community College (Arkansas City, KS), Southeast Community College (Milford, NE), Ridgewater Community College (Hutchinson, MN) and Iowa State University (Ames, IA). Partial funding for this effort was provided by the National Science Foundation.

An outline of the topics covered by this course is as follows:

  1. Differences between film/filmless radiography
  2. Equipment
  3. Process control tests
  4. Defect analysis and applications
  5. Specifications
  6. Procedure development