Exelon Clearsight was contracted to perform a drone-based inspection of a nuclear site’s containment building, per the ASME Section XI IWL standard. Subsection IWL requires a thorough inspection to be performed every five years to ensure there is no degradation or defects in the concrete.
Traditional inspection methods of the containment structure require a climb, rappelling, binoculars and a heavy scaffold build, which can be very costly. The use of drones not only eliminated these safety hazards, but also allowed for better inspection capabilities. The drones needed to be capable of reading characters that were only 0.105” tall from up to 20 feet away.
Traditionally, this inspection would require four to six weeks of on-site time. The Exelon Clearsight team performed the inspection in less than two weeks with only four people.
Over 39,000 square feet of surface was inspected, with identification and high-resolution photographs taken of more than 150 areas of interest. A comprehensive report was prepared and delivered to the customer, including categorization of all suspect areas with photogrammetric measurements for trending purposes. The report included an aerial view of the containment structure with a “defect map” of all identified suspect areas to provide greater insights into the performance of the structure.