Event Notification Report for July 09, 2008
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
07/08/2008 - 07/09/2008
EVENT NUMBERS
44340
General Information or Other
Event Number: 44340
Rep Org: NORTH DAKOTA DEPARTMENT OF HEALTH
Licensee: MIDWEST INDUSTRIAL X-RAY, INC.
Region: 4
City: CASSELTON State: ND
County: CASS
License #: 33-14907-01
Agreement: Y
Docket:
NRC Notified By: DAN HARMAN
HQ OPS Officer: HOWIE CROUCH
Licensee: MIDWEST INDUSTRIAL X-RAY, INC.
Region: 4
City: CASSELTON State: ND
County: CASS
License #: 33-14907-01
Agreement: Y
Docket:
NRC Notified By: DAN HARMAN
HQ OPS Officer: HOWIE CROUCH
Notification Date: 07/09/2008
Notification Time: 17:03 [ET]
Event Date: 07/09/2008
Event Time: 00:00 [MDT]
Last Update Date: 10/02/2008
Notification Time: 17:03 [ET]
Event Date: 07/09/2008
Event Time: 00:00 [MDT]
Last Update Date: 10/02/2008
Emergency Class: NON EMERGENCY
10 CFR Section:
10 CFR Section:
Person (Organization):
MICHAEL HAY (R4)
ROBERT LEWIS (FSME)
MICHAEL HAY (R4)
ROBERT LEWIS (FSME)
NORTH DAKOTA AGREEMENT STATE REPORT - POTENTIAL OVEREXPOSURE FROM RADIOGRAPHY CAMERA
Midwest Industrial X-ray, Inc. was performing radiography at an ethanol plant in Casselton County, ND. After taking a shot, the radiographer was retracting the source when it became detached. The radiographer covered the source with a lead blanket and contacted the company Radiation Safety Officer. The camera contained a 24.5 Ci Ir-192 source.
The licensee transported the source back to their facility. The licensee performed calculations that indicated the radiographer received approximately 4 Rem exposure while securing the source. No calculations were reported concerning the assistant radiographer. The calculations performed by the State of North Dakota indicate that the radiographer received greater than 5 Rem. Both individual's film badges were sent to Landauer laboratories for processing.
The State of North Dakota will be investigating this incident.
* * * UPDATE FROM DAN HARMAN VIA EMAIL TO J. KNOKE AT 1725 EDT ON 07/10/08 * * *
"The doses for the lead radiographer are as follows: The badge reading for this monitoring period (June 20 - Jul 8) 575 mR. The yearly total deep dose is 827 mR."
Notified FSME (Lewis) and R4DO (Hay)
* * * UPDATE ON 7/14/2008 AT 1900 FROM DANIEL HARMAN TO MARK ABRAMOVITZ * * *
This agreement state report update was received via e-mail:
"Initial Assumption: the source was full exposed in the source tube between the camera and the collimator; the exposure time estimate was 2 minutes; estimated average distance to source was 0.3 meters; gamma constant = 0.59; source strength = 24.5 Ci; and estimated exposure was 5.3 mR.
"Investigation Results - Hardware: The camera was a QSA 660B. Maintenance had been performed on this camera two days prior to this event. The source became detached from the wire and lodged inside the camera at or near the connection between the camera and the guide tube. The survey meters used were NDS-2000. Both had recently been calibrated. The one that failed had been sent in for repair in November 2007. The RA-500 worn by [the assistant radiographer] had been sent in twice for repair. We will follow up with asking the company to review the maintenance records for these two devices to determine if they should be replaced ahead of schedule.
"Investigation Results - Personnel and Dose update: the primary person exposed was [the assistant radiographer]. By Thursday afternoon his annual badge exposure data had been compiled, including the expose for this event. This data is as follows: deep total - 825 mR, lens - 839 mR and Shallow - 835 mR. The badge for the period June 20 - July 19 was read by Landauer on July 11, 2008, and indicated 575 mR. Dosimeter data for the badge period showed a dose of 88 mR. The badge reading - the badge period dosimeter data shows an exposure of 487 mR for this event.
"There were four other personnel involved in the actual event and source retrieval. They are (job lead radiographer, dose: 40 mR); (radiographer, dose: 40 mR), (intern, dose: 32 mR) and (RSO, dose: 55 mR). These data were taken from the pocket dosimeters.
"Investigation Results - Source Recovery: There are some inconsistencies between what was stated to have happened and what the investigators believe could have happened. Most relate to positions with respect to the camera/source. We expect to have these resolved by Friday, July 18, 2008."
Notified FSME (Lewis) and R4DO (Johnson).
* * * UPDATE @ 1750 EDT ON 10/2/08 FROM DAN HARMAN TO HOWIE CROUCH VIA EMAIL * * *
"Investigation Results - Hardware: The QSA Model 660B camera and control cable was returned to QSA for evaluation. QSA's evaluation determined the problem was a 'misconnect' not a 'disconnect' of the source assembly from the drive cable. The 'misconnect' was due to wear on the plug assembly, the male connector and the apparent age of the drive cable.
"The NDS 2000 survey meter used by [the assistant radiographer] failed to respond due to a loose battery connection.
"The Alarm Rate Meter worn by [the assistant radiographer] failed to alarm. This meter had been sent to NDS to have the audio transducer replaced in December and was calibrated at that time. After the incident, the meter was tested in Midwest's lab and the meter did not chirp until 750 mR/hr and was continuous at 1000 mR/hr. According to NDS, this is a 'Low Battery' indication. The rate meter [the assistant radiographer] used did not have a low battery indicator light.
"Investigation Results - Conclusions: 1) The alarm rate meter failed due to a low battery condition. 2) The survey meter failed due to a battery disconnect. 3) [The assistant radiographer] read his survey meter while on the platform, next to the camera, saw it read '0', but did not realize the significance of the reading and get off the platform and back on the ground.
"The survey meter was repaired and the battery was replaced in the alarm rate meter. Both devices were returned to service.
"Investigation Results - Department Actions: The North Dakota Department of Health considers this investigation closed. No penalties will be assessed against Midwest Industrial X-Ray, Inc."
Notified R4DO (Bywater) and FSME EO (Bradford).
Midwest Industrial X-ray, Inc. was performing radiography at an ethanol plant in Casselton County, ND. After taking a shot, the radiographer was retracting the source when it became detached. The radiographer covered the source with a lead blanket and contacted the company Radiation Safety Officer. The camera contained a 24.5 Ci Ir-192 source.
The licensee transported the source back to their facility. The licensee performed calculations that indicated the radiographer received approximately 4 Rem exposure while securing the source. No calculations were reported concerning the assistant radiographer. The calculations performed by the State of North Dakota indicate that the radiographer received greater than 5 Rem. Both individual's film badges were sent to Landauer laboratories for processing.
The State of North Dakota will be investigating this incident.
* * * UPDATE FROM DAN HARMAN VIA EMAIL TO J. KNOKE AT 1725 EDT ON 07/10/08 * * *
"The doses for the lead radiographer are as follows: The badge reading for this monitoring period (June 20 - Jul 8) 575 mR. The yearly total deep dose is 827 mR."
Notified FSME (Lewis) and R4DO (Hay)
* * * UPDATE ON 7/14/2008 AT 1900 FROM DANIEL HARMAN TO MARK ABRAMOVITZ * * *
This agreement state report update was received via e-mail:
"Initial Assumption: the source was full exposed in the source tube between the camera and the collimator; the exposure time estimate was 2 minutes; estimated average distance to source was 0.3 meters; gamma constant = 0.59; source strength = 24.5 Ci; and estimated exposure was 5.3 mR.
"Investigation Results - Hardware: The camera was a QSA 660B. Maintenance had been performed on this camera two days prior to this event. The source became detached from the wire and lodged inside the camera at or near the connection between the camera and the guide tube. The survey meters used were NDS-2000. Both had recently been calibrated. The one that failed had been sent in for repair in November 2007. The RA-500 worn by [the assistant radiographer] had been sent in twice for repair. We will follow up with asking the company to review the maintenance records for these two devices to determine if they should be replaced ahead of schedule.
"Investigation Results - Personnel and Dose update: the primary person exposed was [the assistant radiographer]. By Thursday afternoon his annual badge exposure data had been compiled, including the expose for this event. This data is as follows: deep total - 825 mR, lens - 839 mR and Shallow - 835 mR. The badge for the period June 20 - July 19 was read by Landauer on July 11, 2008, and indicated 575 mR. Dosimeter data for the badge period showed a dose of 88 mR. The badge reading - the badge period dosimeter data shows an exposure of 487 mR for this event.
"There were four other personnel involved in the actual event and source retrieval. They are (job lead radiographer, dose: 40 mR); (radiographer, dose: 40 mR), (intern, dose: 32 mR) and (RSO, dose: 55 mR). These data were taken from the pocket dosimeters.
"Investigation Results - Source Recovery: There are some inconsistencies between what was stated to have happened and what the investigators believe could have happened. Most relate to positions with respect to the camera/source. We expect to have these resolved by Friday, July 18, 2008."
Notified FSME (Lewis) and R4DO (Johnson).
* * * UPDATE @ 1750 EDT ON 10/2/08 FROM DAN HARMAN TO HOWIE CROUCH VIA EMAIL * * *
"Investigation Results - Hardware: The QSA Model 660B camera and control cable was returned to QSA for evaluation. QSA's evaluation determined the problem was a 'misconnect' not a 'disconnect' of the source assembly from the drive cable. The 'misconnect' was due to wear on the plug assembly, the male connector and the apparent age of the drive cable.
"The NDS 2000 survey meter used by [the assistant radiographer] failed to respond due to a loose battery connection.
"The Alarm Rate Meter worn by [the assistant radiographer] failed to alarm. This meter had been sent to NDS to have the audio transducer replaced in December and was calibrated at that time. After the incident, the meter was tested in Midwest's lab and the meter did not chirp until 750 mR/hr and was continuous at 1000 mR/hr. According to NDS, this is a 'Low Battery' indication. The rate meter [the assistant radiographer] used did not have a low battery indicator light.
"Investigation Results - Conclusions: 1) The alarm rate meter failed due to a low battery condition. 2) The survey meter failed due to a battery disconnect. 3) [The assistant radiographer] read his survey meter while on the platform, next to the camera, saw it read '0', but did not realize the significance of the reading and get off the platform and back on the ground.
"The survey meter was repaired and the battery was replaced in the alarm rate meter. Both devices were returned to service.
"Investigation Results - Department Actions: The North Dakota Department of Health considers this investigation closed. No penalties will be assessed against Midwest Industrial X-Ray, Inc."
Notified R4DO (Bywater) and FSME EO (Bradford).