Event Notification Report for November 24, 2023

AGREEMENT STATE - DOOR INTERLOCK FAILURE

The following information was provided by the Wisconsin Department of Health Services (the Department) email:

"On Wednesday, November 8, 2023, the licensee was treating an individual in their high dose rate (HDR) suite. During the treatment, while the Ir-192 source was exposed, it was noticed that the door to the suite was ajar. The treatment was immediately paused, and the physicist confirmed that the door was open and that the door interlock was not functioning as required. The staff closed the door, put up caution tape, and maintained constant visual surveillance to ensure no one entered. Treatment was reinitiated and completed according to the written directive.

"On Friday, November 10, 2023, the interlock had not yet been repaired, and the licensee performed another HDR treatment utilizing caution tape and constant surveillance.

"The licensee reported the event to the Department by phone on November 14, 2023.

"The licensee performed an event reconstruction and surveyed at the open door with the Ir-192 source exposed. The highest dose rate of 0.3 mR/hr indicates that no member of the public would have received a dose exceeding public dose limits from this event.

"The patients were unaffected.

"The Department will be performing a reactive inspection on November 20, 2023."

WI Event Report ID Number: WI230022

AGREEMENT STATE - LOST TROXLER GAUGE

The following information was provided by the Texas Department of State Health Services (the Department) via phone and email:

"On November 15, 2023, the Department was notified by the licensee that a Troxler model 3440 moisture/density gauge had been lost. The gauge contains one 8 millicurie Cs-137 source and one 40 millicurie Am-241 source.

"The radiation safety officer (RSO) stated that on November 14, 2023, a licensee technician was performing work at a temporary job site where testing was being performed periodically. While sitting in their truck with the gauge on the tailgate of the truck, the technician realized they needed to go to a second job site about 20 minutes from where he was. When they reached the second job site, the technician realized they had left the gauge on the tailgate.

"The technician notified the licensee's RSO and the licensee conducted multiple searches for the gauge but did not locate the gauge. The RSO was advised to contact local law enforcement about the event. The RSO was advised to check local pawn shops and internet sites such as eBay and Craig's List to watch for the gauge. The RSO does not believe the gauge possesses an exposure risk to any individual. Additional information will be provided as it is received in accordance with SA-300."

Texas Incident Number: 10066

NMED Number: TX230052

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

NON-AGREEMENT STATE REPORT - LOST TROXLER GAUGE
The following information was provided by the licensee via phone conservation:
An NRC licensee lost a portable moisture density gauge while in transit to a testing site. The licensee inadvertently drove to the work location with a Troxler gauge on the work vehicle tailgate. The gauge was last known to be in possession by the licensee at the intersection of Kentucky and Diamond Avenues in Evansville, Indiana. The Troxler Model 3400, SN 20494, contained 9 mCi, Cs-137 and 1320 mCi, Am-241/Be.

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

NON-AGREEMENT STATE REPORT - FAILED INDICATING LIGHT

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).

AGREEMENT STATE REPORT - IODINE-131 OVERDOSE

The following information was provided by the California Department of Public Health (CDPH) via email:

"On November 15, 2023, at 2107 PST, [DELETED], the radiation safety officer (RSO) at City of Hope, reported by email that a patient scheduled to receive an oral administration of 100 mCi (millicuries) of iodine-131 (I-131) was instead orally administered 160 mCi of I-131, an excess of 60 mCi. On November 16, 2023, the RSO calculated that the difference in the prescribed dose to the thyroid (target organ) was 488 rem, and that the difference in the prescribed dose to the whole body effective-dose-equivalent was 62 rem. The licensee will be submitting a 15-day written report with additional details."

The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance:
No patient intervention was reported immediately but may be reported in the 15-day report. The excess activity of 60 mCi and dose of 488 rem will result in a dose to the patient that exceeds the original prescribed dose by more than 50 percent.

A Medical Event may indicate potential problems in a medical facility's use of radioactive materials. It does not necessarily result in harm to the patient.

MEDICAL EVENT - Y-90 POTENTIAL UNDERDOSE

The following information was provided by the UP (Upper Peninsula) Health Systems Marquette via phone in accordance with Headquarters Operations Officers Report Guidance:

On 11/17/23 at 1100 EST at UP Health System Marquette, the radiation safety officer (RSO) determined that a patient received a dose that differed from the prescribed dose by more than 20 percent. The patient was prescribed a dose of 11.34 mCi of Y-90. The target organ was a tumor located in the patient's liver. The dose was administered to the target organ as expected, however, calculations on the remaining radioactivity left over from the administration estimated that the patient received a dose of only 2.82 mCi (24.9 percent of the prescribed dose). The RSO notified the referring physician, and the referring physician will notify the patient. The RSO is currently investigating the cause of the underdose and will submit a 15-day written report to follow up once the investigation is complete.

* * * RETRACTION ON 11/20/23 AT 1111 EST FROM BILL PYLE TO BILL GOTT * * *

The following information was provided by the UP (Upper Peninsula) Health Systems Marquette via phone:

The initial dose estimate was based on incorrect measurements and has been revaluated and the dose was in the acceptable range.

Notified R3DO (Feliz-Adorno) and NMSS Events Notification (via email).

A Medical Event may indicate potential problems in a medical facility's use of radioactive materials. It does not necessarily result in harm to the patient.