The following information was provided by the licensee via phone and in accordance with Headquarters Operations Officers Report Guidance:
On November 11, 2023, at about 1330 EST, at the Cleveland Cliffs Steel Corporation in Dearborn Michigan, the licensee staff noted that the indicating light for a 1 curie Am-241 thickness gauge shutter position was malfunctioning. The light indicated open continuously even though the shutter was closing normally. Operation of the plant continued and the shutter remained in its normally open position measuring the product steel thickness. Shutter position was subsequently checked by radiation measurements to confirm that the indicating light was not indicating correctly. No abnormal exposure resulted and the vendor will troubleshoot and repair. The location of the gauge is not normally manned.
- * * UPDATE ON 11/18/23 AT 1509 EST FROM WAYNE LANGDON TO IAN HOWARD * * *
The following update was received from the licensee via email:
Today, a Thermo Fisher Scientific technician came on site to diagnose the shutter position indicator light issue. It was found that the shutter arm flag was bad. The technician replaced the shutter arm flag with a new one and verified that the unit was properly working. No Cleveland Cliffs employees nor the Thermo Fisher Scientific technician were exposed at any time during the event.
Notified R3DO (Feliz-Adorno) and
NMSS Event Notifications (E-mail).