Information Notice 2009-05, Contamination Events Resulting from Damage to Sealed Radioactive Sources During Gauge Dismantlement and Non-Routine Maintenance Operations: Difference between revisions

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{{#Wiki_filter:ML090370785 UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF FEDERAL AND STATE MATERIALS AND ENVIRONMENTAL MANAGEMENT PROGRAMS WASHINGTON, February 3, 2009 NRC INFORMATION NOTICE 2009-05 CONTAMINATION EVENTS RESULTING FROM DAMAGE TO SEALED RADIOACTIVE SOURCES DURING GAUGE DISMANTLEMENT AND NON-
{{#Wiki_filter:ML090370785 UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF FEDERAL AND STATE MATERIALS AND ENVIRONMENTAL MANAGEMENT PROGRAMS WASHINGTON, February 3, 2009 NRC INFORMATION NOTICE 2009-05 CONTAMINATION EVENTS RESULTING FROM DAMAGE TO SEALED RADIOACTIVE SOURCES DURING GAUGE DISMANTLEMENT AND NON-
ROUTINE MAINTENANCE OPERATIONS  
 
===ROUTINE MAINTENANCE OPERATIONS ===


==ADDRESSEES==
==ADDRESSEES==
Line 23: Line 24:


==PURPOSE==
==PURPOSE==
The U.S. Nuclear Regulatory Commission is issuing this Information Notice (IN) to alert addressees of recently reported events that occurred during gauge dismantlement or non- routine maintenance operations that involved the handling or removal of sealed radioactive source During these events, sealed radioactive sources were damaged or ruptured, leading to both facility and personnel contaminatio It is expected that recipients will review the information for applicability to their facilities and consider actions, as appropriate, to avoid similar incident However, the suggestions contained in this information notice are not new NRC requirements; therefore, no specific action, or written response is require The NRC is providing this IN to the Agreement States for their information and for distribution to their licensees as appropriat DESCRIPTION OF CIRCUMSTANCES In the last three years, NRC has received five event reports, three of them recently, involving gauge dismantlement/disassembly or non-routine maintenance operations of devices that involved the handling or removal of sealed radioactive source Four of these events occurred while personnel were attempting to remove a source holder from a gauge or removing a source from its source holder for the purposes of source disposa One of the events involved non- routine maintenance of a calibration devic The specific circumstances of these events are discussed belo Event 1 An NRC service provider licensee was dismantling gauges for the purpose of source removal and consolidation for disposa A licensee employee attempted to dismantle a frame-type beta gauge containing an approximately 2.29 GBq (62 mCi) strontium-90/yttrium-90 sourc The gauge was over 20 years old and had been in storage at the licensee's facility for over 5 year The employee performing the dismantlement had not previously worked with the particular type of gauge or radioactive sourc The employee removed the source holder from the gauge and then attempted to remove the radioactive source from its source holde The strontium-90/
The U.S. Nuclear Regulatory Commission is issuing this Information Notice (IN) to alert addressees of recently reported events that occurred during gauge dismantlement or non- routine maintenance operations that involved the handling or removal of sealed radioactive source During these events, sealed radioactive sources were damaged or ruptured, leading to both facility and personnel contaminatio It is expected that recipients will review the information for applicability to their facilities and consider actions, as appropriate, to avoid similar incident However, the suggestions contained in this information notice are not new NRC requirements; therefore, no specific action, or written response is require The NRC is providing this IN to the Agreement States for their information and for distribution to their licensees as appropriat  
 
==DESCRIPTION OF CIRCUMSTANCES==
In the last three years, NRC has received five event reports, three of them recently, involving gauge dismantlement/disassembly or non-routine maintenance operations of devices that involved the handling or removal of sealed radioactive source Four of these events occurred while personnel were attempting to remove a source holder from a gauge or removing a source from its source holder for the purposes of source disposa One of the events involved non- routine maintenance of a calibration devic The specific circumstances of these events are discussed belo Event 1 An NRC service provider licensee was dismantling gauges for the purpose of source removal and consolidation for disposa A licensee employee attempted to dismantle a frame-type beta gauge containing an approximately 2.29 GBq (62 mCi) strontium-90/yttrium-90 sourc The gauge was over 20 years old and had been in storage at the licensee's facility for over 5 year The employee performing the dismantlement had not previously worked with the particular type of gauge or radioactive sourc The employee removed the source holder from the gauge and then attempted to remove the radioactive source from its source holde The strontium-90/
yttrium-90 source, designed to emit beta particles, had a 0.076 mm (0.003 inch) stainless steel windo A leak test performed prior to dismantlement did not reveal the presence of removable contaminatio In an attempt to remove the radioactive source from its holder, the employee physically impacted the source window with a screwdriver and also impacted the source holder containing the source onto an unyielding metal surfac Following these actions, an in-process leak test revealed the presence of large amounts of removable contaminatio As a result of the damage to the source, the employee performing the dismantlement activities had considerable external contamination, including on the hands, face, and clothin During on- scene personnel decontamination activities, it was found that the employee also received an intake of strontium-90, as evidenced by the detection of radiation inside the nostril Three other licensee employees were externally contaminated to a lesser exten The employees decontaminated themselves prior to leaving the licensee's facilit The employee performing the dismantlement was taken to a local health care facility for medical evaluation as a precautionary measure and provided several days of urine and fecal samples for bioassay analysi The other three employees provided urine samples for bioassay analysi The dose assessment for the employee performing the dismantlement revealed a total effective dose equivalent of 14.4 mSv (1.44 rem). The radiation doses to the other three employees were considerably lowe The licensee's facility was extensively contaminated and strontium-90/ yttrium-90 was found to be dispersed widely throughout the interior of the licensee's facility, considerably beyond the area where the disassembly had been performed or where contaminated individuals had walked within the facilit Decontamination activities were performed by an appropriately licensed contractor and were completed three months after the even Event 2 During disassembly operations at the facilities of an Agreement State gauge manufacturer and distributor licensee, an employee attempted to remove a radioactive source from its source housing for the purpose of disposa The industrial density/level fixed-type gauge had originally been manufactured by the licensee over 30 years prior and at the time of the incident contained an 11.1 GBq (300 mCi) cesium-137 sealed sourc The source was damaged or breached as a result of an employee's attempt to remove it from the gauge housing using a sa Prior to commencing the dismantlement activities, the employee was unaware that the gauge internals had been custom-configure Therefore, when the gauge was cut open with the saw, the sealed radioactive source was not in the area where the employee expected, and as a result, the radioactive source itself was damaged by the sa As a result of the damage to the source, cesium-137 was dispersed throughout the licensee's source disposal room, contaminating the area with microsphere Emergency procedures were activated by the licensee, and no contamination was detected on the floor outside the source disposal roo The employee that damaged the source exhibited contamination on one hand and one leg; a second employee exhibited contamination on both hands and clothin The employees were decontaminated onsite and sent for medical evaluation as a precautionary measur The two employees provided urine samples for bioassay analysis and also underwent lung countin Calculated doses for the two employees were less than 50 uSv (5 mrem). Decontamination activities were performed by an appropriately licensed contractor and were completed two months after the even Event 3 During disassembly operations at an Agreement State gauge manufacturer and distributor licensee, radioactive sources in two different continuous level fixed-type gauges were breached on the same day, resulting in personnel and facility contaminatio In the first incident, a 0.41 GBq (11 mCi) cesium-137 sealed source in a gauge was breached when an employee cut into the source with a band sa In the second incident, a 0.96 GBq (26 mCi) cesium-137 sealed source in a gauge was breached when the same employee, using a drill, broke the drill bit when it became stuck in the source capsul In both cases, the employee that was dismantling the gauges did not have a clear understanding of the location of the sources within the gauge Radioactive contamination was detected on the employee, throughout the source handling area, and in other portions of the licensee's restricted area, including the gauge manufacturing are The employee involved in the incidents was decontaminated onsite although some contamination remained on the fingertip The employee was sent for medical evaluation as a precautionary measur Contamination on the employee's hands, arms, hair, and clothing was estimated to be 0.37 GBq (10 mCi). Urine samples from the employee were collected for bioassay analysi Whole body counting of the employee was also performe Calculations indicated a committed effective dose equivalent (CEDE) to the employee ranging from 21.3 to 19.4 uSv (2.13 to 1.94 mrem). The licensee's facility was decontaminated by an appropriately licensed contracto Event 4 An employee of an Agreement State manufacturer and distributor licensee attempted to remove an approximately 12 GBq (325 mCi) cesium-137 sealed source from the source housing of a density/level fixed-type gaug At the time of the event, the gauge was approximately 19 years ol Previous attempts had been made to remove the source from the gauge but were unsuccessfu The employee then attempted to gain access to the source by drilling next to where the source was believed to be locate However, the drill nicked and damaged the radioactive sourc As a result of the damage to the source, radioactive material was dispersed in the licensee's facility, contaminating the immediate work are The licensee estimated that less than 0.37 MBq (10 uCi) of cesium-137 was dispersed, contaminating various surfaces, including the drill press, work bench, and floo The licensee's facility was decontaminate The highest radiation dose to an individual was calculated by the licensee to be 10.9 mSv (1.09 rem).
yttrium-90 source, designed to emit beta particles, had a 0.076 mm (0.003 inch) stainless steel windo A leak test performed prior to dismantlement did not reveal the presence of removable contaminatio In an attempt to remove the radioactive source from its holder, the employee physically impacted the source window with a screwdriver and also impacted the source holder containing the source onto an unyielding metal surfac Following these actions, an in-process leak test revealed the presence of large amounts of removable contaminatio As a result of the damage to the source, the employee performing the dismantlement activities had considerable external contamination, including on the hands, face, and clothin During on- scene personnel decontamination activities, it was found that the employee also received an intake of strontium-90, as evidenced by the detection of radiation inside the nostril Three other licensee employees were externally contaminated to a lesser exten The employees decontaminated themselves prior to leaving the licensee's facilit The employee performing the dismantlement was taken to a local health care facility for medical evaluation as a precautionary measure and provided several days of urine and fecal samples for bioassay analysi The other three employees provided urine samples for bioassay analysi The dose assessment for the employee performing the dismantlement revealed a total effective dose equivalent of 14.4 mSv (1.44 rem). The radiation doses to the other three employees were considerably lowe The licensee's facility was extensively contaminated and strontium-90/ yttrium-90 was found to be dispersed widely throughout the interior of the licensee's facility, considerably beyond the area where the disassembly had been performed or where contaminated individuals had walked within the facilit Decontamination activities were performed by an appropriately licensed contractor and were completed three months after the even Event 2 During disassembly operations at the facilities of an Agreement State gauge manufacturer and distributor licensee, an employee attempted to remove a radioactive source from its source housing for the purpose of disposa The industrial density/level fixed-type gauge had originally been manufactured by the licensee over 30 years prior and at the time of the incident contained an 11.1 GBq (300 mCi) cesium-137 sealed sourc The source was damaged or breached as a result of an employee's attempt to remove it from the gauge housing using a sa Prior to commencing the dismantlement activities, the employee was unaware that the gauge internals had been custom-configure Therefore, when the gauge was cut open with the saw, the sealed radioactive source was not in the area where the employee expected, and as a result, the radioactive source itself was damaged by the sa As a result of the damage to the source, cesium-137 was dispersed throughout the licensee's source disposal room, contaminating the area with microsphere Emergency procedures were activated by the licensee, and no contamination was detected on the floor outside the source disposal roo The employee that damaged the source exhibited contamination on one hand and one leg; a second employee exhibited contamination on both hands and clothin The employees were decontaminated onsite and sent for medical evaluation as a precautionary measur The two employees provided urine samples for bioassay analysis and also underwent lung countin Calculated doses for the two employees were less than 50 uSv (5 mrem). Decontamination activities were performed by an appropriately licensed contractor and were completed two months after the even Event 3 During disassembly operations at an Agreement State gauge manufacturer and distributor licensee, radioactive sources in two different continuous level fixed-type gauges were breached on the same day, resulting in personnel and facility contaminatio In the first incident, a 0.41 GBq (11 mCi) cesium-137 sealed source in a gauge was breached when an employee cut into the source with a band sa In the second incident, a 0.96 GBq (26 mCi) cesium-137 sealed source in a gauge was breached when the same employee, using a drill, broke the drill bit when it became stuck in the source capsul In both cases, the employee that was dismantling the gauges did not have a clear understanding of the location of the sources within the gauge Radioactive contamination was detected on the employee, throughout the source handling area, and in other portions of the licensee's restricted area, including the gauge manufacturing are The employee involved in the incidents was decontaminated onsite although some contamination remained on the fingertip The employee was sent for medical evaluation as a precautionary measur Contamination on the employee's hands, arms, hair, and clothing was estimated to be 0.37 GBq (10 mCi). Urine samples from the employee were collected for bioassay analysi Whole body counting of the employee was also performe Calculations indicated a committed effective dose equivalent (CEDE) to the employee ranging from 21.3 to 19.4 uSv (2.13 to 1.94 mrem). The licensee's facility was decontaminated by an appropriately licensed contracto Event 4 An employee of an Agreement State manufacturer and distributor licensee attempted to remove an approximately 12 GBq (325 mCi) cesium-137 sealed source from the source housing of a density/level fixed-type gaug At the time of the event, the gauge was approximately 19 years ol Previous attempts had been made to remove the source from the gauge but were unsuccessfu The employee then attempted to gain access to the source by drilling next to where the source was believed to be locate However, the drill nicked and damaged the radioactive sourc As a result of the damage to the source, radioactive material was dispersed in the licensee's facility, contaminating the immediate work are The licensee estimated that less than 0.37 MBq (10 uCi) of cesium-137 was dispersed, contaminating various surfaces, including the drill press, work bench, and floo The licensee's facility was decontaminate The highest radiation dose to an individual was calculated by the licensee to be 10.9 mSv (1.09 rem).


Event 5 An employee of Agreement State instrument calibration service provider attempted to modify or perform non-routine maintenance on a piece of calibration equipment that contained a radioactive sourc At the time of the incident, the calibration device contained a 1.85 GBq (50 mCi) cesium-137 sealed sourc The device had previously been designed and built by the licensee for their own us The employee used a grinder to grind what was believed to be a metal spacer inside of the calibration devic When contamination was detected by another employee in the vicinity of the work area, the employees recognized that the piece of metal that had been ground actually contained a radioactive sourc As a result, the licensee's machine shop became contaminate Also, due to the tracking of radioactive contamination by personnel, some other areas of the licensee's facility became slightly contaminate The licensee performed some decontamination activities themselves and retained the services of an appropriately licensed contractor to complete the decontamination activitie The licensee identified four individuals that might have been exposed to the contamination even All four individuals underwent whole body countin Three individuals were estimated to have received less than 0.1 mSv (10 mrem) CED The fourth individual, who performed the grinding of the source, is estimated to have received 2.99 mSv (29.2 mrem) CED DISCUSSION The events described above each occurred during gauge dismantlement or non-routine maintenance operations that involved the handling or removal of sealed radioactive source In each event, radiation sources were damaged or breached, resulting in both radioactive contamination of individuals and licensee facilitie In each event, radioactive contamination was confined within the licensee's facility, with no detectable release of radioactive material into the public domai However, some licensee facilities were contaminated significantly, leading to long periods of time of facility closure and in most cases, necessitating decontamination services provided by a contracto Also, in each case, licensee personnel were contaminated, often with both external radioactive contamination and some level of intake of radioactive materia Some employees with a suspected intake of radioactive material were sent for medical evaluation as a precautionary measur Additionally, special dose analysis and assessment methods were necessary in some cases, including urine and fecal bioassay and/or lung or whole body countin Common causal factors have been identified in the events described above that may have contributed to the damage to the radioactive sources, the subsequent release of radioactive material, and the resultant contamination of licensee facilities and personne The common causal factors have been identified as follows: 1. Dismantling/disassembling gauges or performing non-routine maintenance of devices based on intuition rather than reviewing the information contained in the sealed source and device registry (SS&DR) safety analysis or other information available from the source or device manufacturer or vendo . For an unfamiliar radioactive source or device, or in the absence of specific information about the configuration of the radioactive sources within the gauges or devices, licensees did not develop, document, and implement their own procedures to perform the dismantlement or non-routine maintenance activitie . For the incidents that involved dismantlement or disassembly of gauges, the aged and potentially deteriorated condition of the gauges and/or radioactive sources at the time of dismantlement/disassembly was not taken into consideration by licensee personnel that were handling the sources or device This IN serves as a reminder of the importance for licensees to exercise caution when performing licensed activities that involve the handling or removal of sealed radioactive sources in gauges or device Prior to the start of any such activity, licensees should review specific information about the gauge, source holder, and/or devic This includes, as appropriate, information available in the SS&DR or other information from the manufacturer or vendo In the absence of such information, licensees should themselves develop, document, and implement appropriate procedures, as well as train personnel on the procedure When developing procedures, licensees should consider conducting dismantlement/
Event 5 An employee of Agreement State instrument calibration service provider attempted to modify or perform non-routine maintenance on a piece of calibration equipment that contained a radioactive sourc At the time of the incident, the calibration device contained a 1.85 GBq (50 mCi) cesium-137 sealed sourc The device had previously been designed and built by the licensee for their own us The employee used a grinder to grind what was believed to be a metal spacer inside of the calibration devic When contamination was detected by another employee in the vicinity of the work area, the employees recognized that the piece of metal that had been ground actually contained a radioactive sourc As a result, the licensee's machine shop became contaminate Also, due to the tracking of radioactive contamination by personnel, some other areas of the licensee's facility became slightly contaminate The licensee performed some decontamination activities themselves and retained the services of an appropriately licensed contractor to complete the decontamination activitie The licensee identified four individuals that might have been exposed to the contamination even All four individuals underwent whole body countin Three individuals were estimated to have received less than 0.1 mSv (10 mrem) CED The fourth individual, who performed the grinding of the source, is estimated to have received 2.99 mSv (29.2 mrem) CED  
 
==DISCUSSION==
The events described above each occurred during gauge dismantlement or non-routine maintenance operations that involved the handling or removal of sealed radioactive source In each event, radiation sources were damaged or breached, resulting in both radioactive contamination of individuals and licensee facilitie In each event, radioactive contamination was confined within the licensee's facility, with no detectable release of radioactive material into the public domai However, some licensee facilities were contaminated significantly, leading to long periods of time of facility closure and in most cases, necessitating decontamination services provided by a contracto Also, in each case, licensee personnel were contaminated, often with both external radioactive contamination and some level of intake of radioactive materia Some employees with a suspected intake of radioactive material were sent for medical evaluation as a precautionary measur Additionally, special dose analysis and assessment methods were necessary in some cases, including urine and fecal bioassay and/or lung or whole body countin Common causal factors have been identified in the events described above that may have contributed to the damage to the radioactive sources, the subsequent release of radioactive material, and the resultant contamination of licensee facilities and personne The common causal factors have been identified as follows: 1. Dismantling/disassembling gauges or performing non-routine maintenance of devices based on intuition rather than reviewing the information contained in the sealed source and device registry (SS&DR) safety analysis or other information available from the source or device manufacturer or vendo . For an unfamiliar radioactive source or device, or in the absence of specific information about the configuration of the radioactive sources within the gauges or devices, licensees did not develop, document, and implement their own procedures to perform the dismantlement or non-routine maintenance activitie . For the incidents that involved dismantlement or disassembly of gauges, the aged and potentially deteriorated condition of the gauges and/or radioactive sources at the time of dismantlement/disassembly was not taken into consideration by licensee personnel that were handling the sources or device This IN serves as a reminder of the importance for licensees to exercise caution when performing licensed activities that involve the handling or removal of sealed radioactive sources in gauges or device Prior to the start of any such activity, licensees should review specific information about the gauge, source holder, and/or devic This includes, as appropriate, information available in the SS&DR or other information from the manufacturer or vendo In the absence of such information, licensees should themselves develop, document, and implement appropriate procedures, as well as train personnel on the procedure When developing procedures, licensees should consider conducting dismantlement/
disassembly and other non-routine maintenance activities in a deliberate, stepwise manner, including conducting routine monitoring for radioactive contamination to promptly detect potential problem Additionally, procedures should take into consideration actions that might be necessary to mitigate the consequences of radioactive source damage/rupture incident The availability of appropriate radiation detection equipment would assist personnel in determining the scope and extent of radiological contamination; which would, in part, help determine the necessary level of respons Regarding training, licensees might remain mindful that a successful training program should thoroughly familiarize employees with actions to take to limit the spread of contamination within licensee facilities and actions to take to successfully decontaminate personne Licensees should consider having appropriate supplies available in the event that the decontamination of personnel is necessar Furthermore, a successful training program would help employees recognize actions that may be necessary to prevent the spread of radioactive contamination into the public domai Finally, licensee employees should be trained to recognize conditions under which it might be necessary to seek external assistance, or notify as appropriate, NRC or other appropriate regulatory agencie  
disassembly and other non-routine maintenance activities in a deliberate, stepwise manner, including conducting routine monitoring for radioactive contamination to promptly detect potential problem Additionally, procedures should take into consideration actions that might be necessary to mitigate the consequences of radioactive source damage/rupture incident The availability of appropriate radiation detection equipment would assist personnel in determining the scope and extent of radiological contamination; which would, in part, help determine the necessary level of respons Regarding training, licensees might remain mindful that a successful training program should thoroughly familiarize employees with actions to take to limit the spread of contamination within licensee facilities and actions to take to successfully decontaminate personne Licensees should consider having appropriate supplies available in the event that the decontamination of personnel is necessar Furthermore, a successful training program would help employees recognize actions that may be necessary to prevent the spread of radioactive contamination into the public domai Finally, licensee employees should be trained to recognize conditions under which it might be necessary to seek external assistance, or notify as appropriate, NRC or other appropriate regulatory agencie  


Revision as of 02:54, 19 February 2018

Contamination Events Resulting from Damage to Sealed Radioactive Sources During Gauge Dismantlement and Non-Routine Maintenance Operations
ML090370785
Person / Time
Issue date: 02/03/2009
Revision: 0
From: Lewis R J
NRC/FSME/DMSSA
To:
Sepulveda, L
References
IN-09-005 IN-09-005
Download: ML090370785 (8)
v • d • e


ML090370785 UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF FEDERAL AND STATE MATERIALS AND ENVIRONMENTAL MANAGEMENT PROGRAMS WASHINGTON, February 3, 2009 NRC INFORMATION NOTICE 2009-05 CONTAMINATION EVENTS RESULTING FROM DAMAGE TO SEALED RADIOACTIVE SOURCES DURING GAUGE DISMANTLEMENT AND NON-

ROUTINE MAINTENANCE OPERATIONS

ADDRESSEES

All U.S. Nuclear Regulatory Commission (NRC) materials licensee All Agreement State Radiation Control Program Directors and State Liaison Officer

PURPOSE

The U.S. Nuclear Regulatory Commission is issuing this Information Notice (IN) to alert addressees of recently reported events that occurred during gauge dismantlement or non- routine maintenance operations that involved the handling or removal of sealed radioactive source During these events, sealed radioactive sources were damaged or ruptured, leading to both facility and personnel contaminatio It is expected that recipients will review the information for applicability to their facilities and consider actions, as appropriate, to avoid similar incident However, the suggestions contained in this information notice are not new NRC requirements; therefore, no specific action, or written response is require The NRC is providing this IN to the Agreement States for their information and for distribution to their licensees as appropriat

DESCRIPTION OF CIRCUMSTANCES

In the last three years, NRC has received five event reports, three of them recently, involving gauge dismantlement/disassembly or non-routine maintenance operations of devices that involved the handling or removal of sealed radioactive source Four of these events occurred while personnel were attempting to remove a source holder from a gauge or removing a source from its source holder for the purposes of source disposa One of the events involved non- routine maintenance of a calibration devic The specific circumstances of these events are discussed belo Event 1 An NRC service provider licensee was dismantling gauges for the purpose of source removal and consolidation for disposa A licensee employee attempted to dismantle a frame-type beta gauge containing an approximately 2.29 GBq (62 mCi) strontium-90/yttrium-90 sourc The gauge was over 20 years old and had been in storage at the licensee's facility for over 5 year The employee performing the dismantlement had not previously worked with the particular type of gauge or radioactive sourc The employee removed the source holder from the gauge and then attempted to remove the radioactive source from its source holde The strontium-90/

yttrium-90 source, designed to emit beta particles, had a 0.076 mm (0.003 inch) stainless steel windo A leak test performed prior to dismantlement did not reveal the presence of removable contaminatio In an attempt to remove the radioactive source from its holder, the employee physically impacted the source window with a screwdriver and also impacted the source holder containing the source onto an unyielding metal surfac Following these actions, an in-process leak test revealed the presence of large amounts of removable contaminatio As a result of the damage to the source, the employee performing the dismantlement activities had considerable external contamination, including on the hands, face, and clothin During on- scene personnel decontamination activities, it was found that the employee also received an intake of strontium-90, as evidenced by the detection of radiation inside the nostril Three other licensee employees were externally contaminated to a lesser exten The employees decontaminated themselves prior to leaving the licensee's facilit The employee performing the dismantlement was taken to a local health care facility for medical evaluation as a precautionary measure and provided several days of urine and fecal samples for bioassay analysi The other three employees provided urine samples for bioassay analysi The dose assessment for the employee performing the dismantlement revealed a total effective dose equivalent of 14.4 mSv (1.44 rem). The radiation doses to the other three employees were considerably lowe The licensee's facility was extensively contaminated and strontium-90/ yttrium-90 was found to be dispersed widely throughout the interior of the licensee's facility, considerably beyond the area where the disassembly had been performed or where contaminated individuals had walked within the facilit Decontamination activities were performed by an appropriately licensed contractor and were completed three months after the even Event 2 During disassembly operations at the facilities of an Agreement State gauge manufacturer and distributor licensee, an employee attempted to remove a radioactive source from its source housing for the purpose of disposa The industrial density/level fixed-type gauge had originally been manufactured by the licensee over 30 years prior and at the time of the incident contained an 11.1 GBq (300 mCi) cesium-137 sealed sourc The source was damaged or breached as a result of an employee's attempt to remove it from the gauge housing using a sa Prior to commencing the dismantlement activities, the employee was unaware that the gauge internals had been custom-configure Therefore, when the gauge was cut open with the saw, the sealed radioactive source was not in the area where the employee expected, and as a result, the radioactive source itself was damaged by the sa As a result of the damage to the source, cesium-137 was dispersed throughout the licensee's source disposal room, contaminating the area with microsphere Emergency procedures were activated by the licensee, and no contamination was detected on the floor outside the source disposal roo The employee that damaged the source exhibited contamination on one hand and one leg; a second employee exhibited contamination on both hands and clothin The employees were decontaminated onsite and sent for medical evaluation as a precautionary measur The two employees provided urine samples for bioassay analysis and also underwent lung countin Calculated doses for the two employees were less than 50 uSv (5 mrem). Decontamination activities were performed by an appropriately licensed contractor and were completed two months after the even Event 3 During disassembly operations at an Agreement State gauge manufacturer and distributor licensee, radioactive sources in two different continuous level fixed-type gauges were breached on the same day, resulting in personnel and facility contaminatio In the first incident, a 0.41 GBq (11 mCi) cesium-137 sealed source in a gauge was breached when an employee cut into the source with a band sa In the second incident, a 0.96 GBq (26 mCi) cesium-137 sealed source in a gauge was breached when the same employee, using a drill, broke the drill bit when it became stuck in the source capsul In both cases, the employee that was dismantling the gauges did not have a clear understanding of the location of the sources within the gauge Radioactive contamination was detected on the employee, throughout the source handling area, and in other portions of the licensee's restricted area, including the gauge manufacturing are The employee involved in the incidents was decontaminated onsite although some contamination remained on the fingertip The employee was sent for medical evaluation as a precautionary measur Contamination on the employee's hands, arms, hair, and clothing was estimated to be 0.37 GBq (10 mCi). Urine samples from the employee were collected for bioassay analysi Whole body counting of the employee was also performe Calculations indicated a committed effective dose equivalent (CEDE) to the employee ranging from 21.3 to 19.4 uSv (2.13 to 1.94 mrem). The licensee's facility was decontaminated by an appropriately licensed contracto Event 4 An employee of an Agreement State manufacturer and distributor licensee attempted to remove an approximately 12 GBq (325 mCi) cesium-137 sealed source from the source housing of a density/level fixed-type gaug At the time of the event, the gauge was approximately 19 years ol Previous attempts had been made to remove the source from the gauge but were unsuccessfu The employee then attempted to gain access to the source by drilling next to where the source was believed to be locate However, the drill nicked and damaged the radioactive sourc As a result of the damage to the source, radioactive material was dispersed in the licensee's facility, contaminating the immediate work are The licensee estimated that less than 0.37 MBq (10 uCi) of cesium-137 was dispersed, contaminating various surfaces, including the drill press, work bench, and floo The licensee's facility was decontaminate The highest radiation dose to an individual was calculated by the licensee to be 10.9 mSv (1.09 rem).

Event 5 An employee of Agreement State instrument calibration service provider attempted to modify or perform non-routine maintenance on a piece of calibration equipment that contained a radioactive sourc At the time of the incident, the calibration device contained a 1.85 GBq (50 mCi) cesium-137 sealed sourc The device had previously been designed and built by the licensee for their own us The employee used a grinder to grind what was believed to be a metal spacer inside of the calibration devic When contamination was detected by another employee in the vicinity of the work area, the employees recognized that the piece of metal that had been ground actually contained a radioactive sourc As a result, the licensee's machine shop became contaminate Also, due to the tracking of radioactive contamination by personnel, some other areas of the licensee's facility became slightly contaminate The licensee performed some decontamination activities themselves and retained the services of an appropriately licensed contractor to complete the decontamination activitie The licensee identified four individuals that might have been exposed to the contamination even All four individuals underwent whole body countin Three individuals were estimated to have received less than 0.1 mSv (10 mrem) CED The fourth individual, who performed the grinding of the source, is estimated to have received 2.99 mSv (29.2 mrem) CED

DISCUSSION

The events described above each occurred during gauge dismantlement or non-routine maintenance operations that involved the handling or removal of sealed radioactive source In each event, radiation sources were damaged or breached, resulting in both radioactive contamination of individuals and licensee facilitie In each event, radioactive contamination was confined within the licensee's facility, with no detectable release of radioactive material into the public domai However, some licensee facilities were contaminated significantly, leading to long periods of time of facility closure and in most cases, necessitating decontamination services provided by a contracto Also, in each case, licensee personnel were contaminated, often with both external radioactive contamination and some level of intake of radioactive materia Some employees with a suspected intake of radioactive material were sent for medical evaluation as a precautionary measur Additionally, special dose analysis and assessment methods were necessary in some cases, including urine and fecal bioassay and/or lung or whole body countin Common causal factors have been identified in the events described above that may have contributed to the damage to the radioactive sources, the subsequent release of radioactive material, and the resultant contamination of licensee facilities and personne The common causal factors have been identified as follows: 1. Dismantling/disassembling gauges or performing non-routine maintenance of devices based on intuition rather than reviewing the information contained in the sealed source and device registry (SS&DR) safety analysis or other information available from the source or device manufacturer or vendo . For an unfamiliar radioactive source or device, or in the absence of specific information about the configuration of the radioactive sources within the gauges or devices, licensees did not develop, document, and implement their own procedures to perform the dismantlement or non-routine maintenance activitie . For the incidents that involved dismantlement or disassembly of gauges, the aged and potentially deteriorated condition of the gauges and/or radioactive sources at the time of dismantlement/disassembly was not taken into consideration by licensee personnel that were handling the sources or device This IN serves as a reminder of the importance for licensees to exercise caution when performing licensed activities that involve the handling or removal of sealed radioactive sources in gauges or device Prior to the start of any such activity, licensees should review specific information about the gauge, source holder, and/or devic This includes, as appropriate, information available in the SS&DR or other information from the manufacturer or vendo In the absence of such information, licensees should themselves develop, document, and implement appropriate procedures, as well as train personnel on the procedure When developing procedures, licensees should consider conducting dismantlement/

disassembly and other non-routine maintenance activities in a deliberate, stepwise manner, including conducting routine monitoring for radioactive contamination to promptly detect potential problem Additionally, procedures should take into consideration actions that might be necessary to mitigate the consequences of radioactive source damage/rupture incident The availability of appropriate radiation detection equipment would assist personnel in determining the scope and extent of radiological contamination; which would, in part, help determine the necessary level of respons Regarding training, licensees might remain mindful that a successful training program should thoroughly familiarize employees with actions to take to limit the spread of contamination within licensee facilities and actions to take to successfully decontaminate personne Licensees should consider having appropriate supplies available in the event that the decontamination of personnel is necessar Furthermore, a successful training program would help employees recognize actions that may be necessary to prevent the spread of radioactive contamination into the public domai Finally, licensee employees should be trained to recognize conditions under which it might be necessary to seek external assistance, or notify as appropriate, NRC or other appropriate regulatory agencie

CONTACT

S This IN requires no specific action or written respons If you have any questions about the information in this notice, please contact one of the technical contacts listed below or the appropriate regional offic /RA/ Robert Lewis, Director Division of Materials Safety and State Agreements Office of Federal and State Materials and Environmental Programs Technical Contacts: Lymari Sepulveda; FSME (301) 415-5619 E-mail: Lymari.Sepulveda@nrc.gov Janine F. Katanic, Ph.D., CHP; FSME (817) 860-8151 E-mail: Janine.Katanic@nrc.gov

Enclosure:

List of Recently Issued FSME/NMSS Generic Communications

CONTACT

S This IN requires no specific action or written respons If you have any questions about the information in this notice, please contact one of the technical contacts listed below or the appropriate regional offic /RA/

Robert Lewis, Director Division of Materials Safety and State Agreements Office of Federal and State Materials and Environmental Programs

Technical Contacts: Lymari Sepulveda; FSME (301) 415-5619 E-mail: Lymari.Sepulveda@nrc.gov Janine F. Katanic, Ph.D., CHP; FSME (817) 860-8151 E-mail: Janine.Katanic@nrc.gov

Enclosure:

List of Recently Issued FSME/NMSS Generic Communications

ML090370785 OFFICE DMSSA/ASPB DMSSA/LB DMSSA/ASPB NAME JFKatanic: sxg6 LSepulveda ADWhite DATE 01/08/09 01/09/09 01/09/09 OFFICE DMSSA/LB DMSSA/RMSB DMSSA NAME PRathbun AMcIntosh RLewis DATE 02/03/09 02/03/09 03/03/09 OFFICIAL RECORD COPY IN 2009-05 List of Recently Issued Office of Federal and State Material and Environmental Management Programs Generic Communications Date GC No. Subject

Addressees

05/13/08 RIS-2008-10 Notice Regarding Forthcoming Federal Firearms Background Checks All U.S. Nuclear Regulatory Commission licensees, certificate holders, and applicants for a license or certificate of compliance who use armed security personnel as part of their physical protection system and security organization. All Radiation Control Program Directors and State Liaison Officers. 06/16/08 RIS-2008-13 Status And Plans for Implementation of NRC Regulatory Authority for Certain Naturally Occurring and Accelerator-Produced Radioactive Material All U.S. Nuclear Regulatory Commission materials licensees, Radiation Control Program Directors, State Liaison Officers, and the NRC's Advisory Committee on the Medical Uses of Isotopes 07/18/08 RIS-2008-17 Voluntary Security Enhancements for Self-Contained Irradiators Containing Cesium Chloride Sources All U.S. Nuclear Regulatory Commission Materials Licensees Authorized to Possess Self-Contained Irradiators Containing Cesium Chloride (CsCl) ; all Agreement State Radiation Control Program Directors and State Liaison Officers; all members of the Advisory Committee on the Medical Uses of Isotopes. 10/03/08 RIS-2008-23 The Global Threat Reduction Initiative (GTRI) Domestic Threat Reduction Program & Federally Funded Voluntary Security Enhancements For High-Risk Radiological Material All U.S. Nuclear Regulatory Commission Materials Licensees authorized to possess Category 1 or Category 2 quantities of radioactive materials. All Agreement State Radiation Control Program Directors and State Liaison Officers. Members of the Advisory Committee on the Medical Uses of Isotopes 10/03/08 RIS-2008-24 Security Responsibilities Of Service Providers and Client Licensees All U.S. Nuclear Regulatory Commission licensees that hire service providers to install, service, repair, maintain, relocate, exchange, or transport radioactive materials in quantities of concern, service provider licensees, Agreement State Radiation Control Program Directors, and State Liaison Officers 12/22/08 RIS-2008-10, Suppl. 1 Notice Regarding Forthcoming Federal Firearms Background Checks All U.S. Nuclear Regulatory Commission licensees, certificate holders, and applicants for a license or certificate of compliance who use armed security personnel as part of their physical protection system and security organizatio All Radiation Control Program Directors and State Liaison Officers Note: This list contains the six most recently issued generic communications, issued by the Office of Federal and State Materials and Environmental Management Programs (FSME). A full listing of all generic communications may be viewed at the NRC public website at the following address: http://www.nrc.gov/reading-rm/doc-collections/gen-comm/index.html


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