Digital Detector Array Radiography – DDA RT

Digital Detector Array (DDA) Radiography – Clear Immediate Records

DDA1TextIRISNDT applies DDA radiography to obtain crystal clear images of the cross-sections of components (many operating and with insulation). Unlike Computed Radiography (CR), with DDA one can see an image immediately without processing through a computer. Different than traditional RT with film, an image develops without processing (and immediately). The digital image serves as a chronological record of the condition of the component; it can be stored, accessed and compared as easily as any other digital data.

IRISNDT personnel use DDA:

  • To monitor pitting and overall losses of piping through profile images (shadow shots).
  • To examine insulated and non-insulated piping components.
  • To examine for corrosion under insulation.
  • To monitor the erosion/corrosion losses of components within insulated piping.
  • To allow personnel from multiple remote locations to view the data on FTP sites.
  • To monitor the operating (open/close) condition of valves.
  • To examine rubber components for fabrication flaws.
  • To assess geophysical core samples.


DDA4TextWith DDA radiography one:

  • Saves time and improves productivity over conventional film applications. The exposure time is shorter than that needed for film.
  • Views multiple components (valves, pipe, fittings and threaded parts) all in the same image.
  • Reduces the number of shots (and radiation time) needed to assess piping conditions.
  • Can adjust brightness and contrast.
  • Can magnify and process images.
  • Can measure dimensions and calculate remaining thickness values.
  • Can improve image evaluation.
  • Operates on 120volt or on battery power.
  • Works with Ir-192, Co-60 and X-ray sources.

DDA Fundamentals
To obtain DDA radiographs, one follows a digital camera like work process. The DDA panels have scintillators that convert radiation to light; the panels further process the light to obtain digital radiographs.


On-Site Considerations
Safety is a fundamental consideration when using radiation. Clearance of areas adjacent to the component from persons or items that may be affected by radiation is required. A significant radiation dose can cause physical changes in the human body. Strict Federal and Provincial regulations, coupled with highly trained and qualified personnel ensure the safety of everyone.