The following is a summary of information received from the U.S. Navy via phone and email:
On March 5, 2021, the it was discovered that IBIS units (400 micro Ci total) had not been properly removed from 4 helicopter blades that were sent for recycling. The IBIS units were discovered when the detectors alarmed at the recycling facility in Bedford, IN. The blades were redirected to the Army Joint Munitions Command Morris Consolidation facility in Rock Island, IL for proper disposal.
Based on the shipping paperwork, the helicopter blades that contained the four IBIS were received at the recycling facility on 11/17/2020, and were picked up from the facility on 3/16/2021.
The highest reading was 0.7 mR/hr on contact without the cover installed for one blade. For the 3 other blades in their casing, needle deflection was observed, but had no appreciable dose rate.
It is not likely that personnel spent an appreciable amount of time in the vicinity of the helicopter blades.
THIS MATERIAL EVENT CONTAINS A 'Less than Cat 3' LEVEL OF RADIOACTIVE MATERIAL
Sources that are "Less than
IAEA Category 3 sources," are either sources that are very unlikely to cause permanent injury to individuals or contain a very small amount of radioactive material that would not cause any permanent injury. Some of these sources, such as
moisture density gauges or thickness
gauges that are Category 4, the amount of unshielded radioactive material, if not safely managed or securely protected, could possibly - although it is unlikely - temporarily injure someone who handled it or were otherwise in contact with it, or who were close to it for a period of many weeks. For additional information go to
http://www-pub.iaea.org/MTCD/publications/PDF/Pub1227_web.pdf