ENS 55015: Difference between revisions

v t e ENS Event
06:00 Nov 16, 2020
Title	Stuck Open Shutter
Event Description	The following information was obtained from the State of Iowa via email: A maintenance technician at the 3M facility in Knoxville, Iowa discovered that a Thermo Fisher Scientific model SULP-77A fixed gauging device containing 661 milliCuries of Krypton-85 had a shutter that was stuck open and would not close. This discovery occurred when the production line was shutdown for routine maintenance. The RSO [Radiation Safety Officer] and backup RSO were notified and the gauge was isolated with caution tape to prevent personnel from getting close to the device. 3M maintenance personnel are authorized to perform shutter repair under the supervision of the RSO or backup RSO by Iowa radioactive materials license number 0042-1-63-FG. The licensee will provide a written follow-up report once repairs have been completed and the cause of the failure identified. The licensee had a service provider operating under reciprocity with Iowa onsite November 17, 2020 to troubleshoot and repair the gauge. The root cause of the stuck shutter was a broken shutter return spring. A new shutter operating cylinder with a new return spring was installed and the gauge shutter was tested and found to be operating correctly. To minimize the chance of future shutter closure failures, the shutter operating cylinders will be replaced for all beta gauges of the same model that are currently in use at the site. Cylinder replacement will occur during future planned maintenance activities. These failures are exceedingly rare. This is the first occurrence in more than 20 years of using these gauges. The site is considering implementing a preventative maintenance replacement of these cylinders every 10 years. Iowa report number: IA200004

ENS 55015 +/-
Where
3M Knoxville, Iowa (NRC Region 3)
License number:	0042163FG
Organization:	Iowa Department Of Public Health
Reporting

Agreement State
Time - Person (Reporting Time:+363.92 h15.163 days <br />2.166 weeks <br />0.498 months <br />)
Opened:	Randal Dahlin 09:55 Dec 1, 2020
NRC Officer:	Howie Crouch
Last Updated:	Dec 8, 2020
55015 - NRC Website
v • d • e

v t e Emergency Notification System
3M with Agreement State
WEEKMONTHYEAR2022-07-07T20:15:00 [Table view]
[ENS list for 3M]

@@ Line 10: / Line 10: @@
 | utype =
 | cfr = Agreement State
-| emergency class =  Non Emergency
+| emergency class = Non Emergency
 | notification date = 12/01/2020 09:55
 | notification by = Randal Dahlin

ENS 55015: Difference between revisions

Latest revision as of 12:08, 15 January 2021

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ENS 55015: Difference between revisions

Latest revision as of 12:08, 15 January 2021

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