Event Notification Report for April 01, 2024
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
03/31/2024 - 04/01/2024
Non-Agreement State
Event Number: 57044
Rep Org: US Army
Licensee: US Army
Region: 3
City: Detroit State: MI
County:
License #: 21-32838-01
Agreement: N
Docket:
NRC Notified By: Nathan Krzyaniak
HQ OPS Officer: Bill Gott
Licensee: US Army
Region: 3
City: Detroit State: MI
County:
License #: 21-32838-01
Agreement: N
Docket:
NRC Notified By: Nathan Krzyaniak
HQ OPS Officer: Bill Gott
Notification Date: 03/22/2024
Notification Time: 08:35 [ET]
Event Date: 03/21/2024
Event Time: 17:00 [EDT]
Last Update Date: 03/22/2024
Notification Time: 08:35 [ET]
Event Date: 03/21/2024
Event Time: 17:00 [EDT]
Last Update Date: 03/22/2024
Emergency Class: Non Emergency
10 CFR Section:
20.2201(a)(1)(i) - Lost/Stolen LNM>1000x
10 CFR Section:
20.2201(a)(1)(i) - Lost/Stolen LNM>1000x
Person (Organization):
Hills, David (R3DO)
NMSS_EVENTS_NOTIFICATION (EMAIL)
ILTAB (EMAIL)
Hills, David (R3DO)
NMSS_EVENTS_NOTIFICATION (EMAIL)
ILTAB (EMAIL)
LOST TRITIUM AIMING POST LIGHTS
The following information was provided by the licensee:
At around 1700 CDT on March 21, 2024, the Detroit Army Arsenal's radiation safety officer (RSO) noticed a picture of two Army M58 Aiming Post Lights, which typically contain 5 Ci of tritium each, on a Reddit sub-group. The post indicated that the devices were a "going away gift" from the Army, and that the individual was no longer in the Army. The sealed sources appeared to be intact, but the RSO could not see the serial numbers.
The RSO plans on reporting this to his chain of command and to the Army Criminal Investigative Service.
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
The following information was provided by the licensee:
At around 1700 CDT on March 21, 2024, the Detroit Army Arsenal's radiation safety officer (RSO) noticed a picture of two Army M58 Aiming Post Lights, which typically contain 5 Ci of tritium each, on a Reddit sub-group. The post indicated that the devices were a "going away gift" from the Army, and that the individual was no longer in the Army. The sealed sources appeared to be intact, but the RSO could not see the serial numbers.
The RSO plans on reporting this to his chain of command and to the Army Criminal Investigative Service.
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
Agreement State
Event Number: 57048
Rep Org: Arkansas Department of Health
Licensee: Central AR Rad Therapy Institute
Region: 4
City: Little Rock State: AR
County:
License #: CARTI ARK-0954-02200
Agreement: Y
Docket:
NRC Notified By: Susan Elliott
HQ OPS Officer: Tenisha Meadows
Licensee: Central AR Rad Therapy Institute
Region: 4
City: Little Rock State: AR
County:
License #: CARTI ARK-0954-02200
Agreement: Y
Docket:
NRC Notified By: Susan Elliott
HQ OPS Officer: Tenisha Meadows
Notification Date: 03/25/2024
Notification Time: 14:04 [ET]
Event Date: 02/07/2024
Event Time: 00:00 [CDT]
Last Update Date: 03/25/2024
Notification Time: 14:04 [ET]
Event Date: 02/07/2024
Event Time: 00:00 [CDT]
Last Update Date: 03/25/2024
Emergency Class: Non Emergency
10 CFR Section:
Agreement State
10 CFR Section:
Agreement State
Person (Organization):
Kellar, Ray (R4DO)
NMSS_EVENTS_NOTIFICATION (EMAIL)
Kellar, Ray (R4DO)
NMSS_EVENTS_NOTIFICATION (EMAIL)
AGREEMENT STATE REPORT - Y-90 MICROSPHERE MISADMINISTRATION
The following information was provided by the Arkansas Department of Health, Radiation Control Radioactive Material Program (the Agency) via email:
"The radiation safety officer for Central Arkansas Radiation Therapy Institute (CARTI) contacted the Agency on March 21, 2024, to advise of a yttrium-90 (Y-90) microsphere therapy administration in which the patient received 20 percent greater than the prescribed dose. The administration occurred on February 7, 2024. Treatment was only to one side of the liver. The amount was localized to the liver. The physician felt the delivered dose was clinically effective, and no further treatment is planned. No adverse patient impacts are expected.
"The discovery was made during a quarterly review of their written directive on March 20, 2024.
"The Agency is awaiting further information from the licensee."
Arkansas Event #: AR-2024-2
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.
The following information was provided by the Arkansas Department of Health, Radiation Control Radioactive Material Program (the Agency) via email:
"The radiation safety officer for Central Arkansas Radiation Therapy Institute (CARTI) contacted the Agency on March 21, 2024, to advise of a yttrium-90 (Y-90) microsphere therapy administration in which the patient received 20 percent greater than the prescribed dose. The administration occurred on February 7, 2024. Treatment was only to one side of the liver. The amount was localized to the liver. The physician felt the delivered dose was clinically effective, and no further treatment is planned. No adverse patient impacts are expected.
"The discovery was made during a quarterly review of their written directive on March 20, 2024.
"The Agency is awaiting further information from the licensee."
Arkansas Event #: AR-2024-2
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.
Agreement State
Event Number: 57049
Rep Org: California Radiation Control Prgm
Licensee: University of California San Francisco Medical Center
Region: 4
City: San Francisco State: CA
County:
License #: 1725-38
Agreement: Y
Docket:
NRC Notified By: Gregg Cohn
HQ OPS Officer: Tenisha Meadows
Licensee: University of California San Francisco Medical Center
Region: 4
City: San Francisco State: CA
County:
License #: 1725-38
Agreement: Y
Docket:
NRC Notified By: Gregg Cohn
HQ OPS Officer: Tenisha Meadows
Notification Date: 03/25/2024
Notification Time: 15:48 [ET]
Event Date: 03/24/2024
Event Time: 00:00 [PDT]
Last Update Date: 03/25/2024
Notification Time: 15:48 [ET]
Event Date: 03/24/2024
Event Time: 00:00 [PDT]
Last Update Date: 03/25/2024
Emergency Class: Non Emergency
10 CFR Section:
Agreement State
10 CFR Section:
Agreement State
Person (Organization):
Kellar, Ray (R4DO)
NMSS_EVENTS_NOTIFICATION (EMAIL)
Kellar, Ray (R4DO)
NMSS_EVENTS_NOTIFICATION (EMAIL)
AGREEMENT STATE REPORT - Y-90 THERAPY MISADMINISTRATION
The following information was received from the California Department of Public Health, Radiological Health Branch (RHB) via email:
"On 3/24/24, the alternate radiation safety officer phoned the RHB to report a medical event associated with a yttrium-90 (Y-90) therapy. A patient receiving Y-90 therapy was underdosed by more than 20 percent from the planned dose.
"RHB will investigate."
California Report Number: 032424
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.
The following information was received from the California Department of Public Health, Radiological Health Branch (RHB) via email:
"On 3/24/24, the alternate radiation safety officer phoned the RHB to report a medical event associated with a yttrium-90 (Y-90) therapy. A patient receiving Y-90 therapy was underdosed by more than 20 percent from the planned dose.
"RHB will investigate."
California Report Number: 032424
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.
Agreement State
Event Number: 57051
Rep Org: WA Office of Radiation Protection
Licensee: Radius Recycling
Region: 4
City: Burbank State: WA
County:
License #:
Agreement: Y
Docket:
NRC Notified By: James Killingbeck
HQ OPS Officer: Tenisha Meadows
Licensee: Radius Recycling
Region: 4
City: Burbank State: WA
County:
License #:
Agreement: Y
Docket:
NRC Notified By: James Killingbeck
HQ OPS Officer: Tenisha Meadows
Notification Date: 03/25/2024
Notification Time: 18:54 [ET]
Event Date: 04/04/2022
Event Time: 00:00 [PDT]
Last Update Date: 03/25/2024
Notification Time: 18:54 [ET]
Event Date: 04/04/2022
Event Time: 00:00 [PDT]
Last Update Date: 03/25/2024
Emergency Class: Non Emergency
10 CFR Section:
Agreement State
10 CFR Section:
Agreement State
Person (Organization):
Kellar, Ray (R4DO)
NMSS_EVENTS_NOTIFICATION (EMAIL)
Kellar, Ray (R4DO)
NMSS_EVENTS_NOTIFICATION (EMAIL)
AGREEMENT STATE REPORT - FOUND SOURCE
The following information was received from the Washington State Department of Health, Office of Radiation Protection (the Department) via email:
"Action Towing LLC transported a car to the Schnitzer Steel Industries scrap metal facility, and it triggered the scrap yard's radiation detectors. The scrap yard staff measured about 35 micro roentgen/hour on the outside of the car. Officials at Schnitzer Steel Industries contacted the Department which resulted in an evaluation of the concern and issuance of a DOT special permit so that the radioactive car could be returned to Action Towing LLC for proper handling.
"The Action Towing office manager was informed that the staff had seen some sort of radiation equipment in the car, so the Department requested pictures of the equipment. The pictures showed an old military Geiger-Mueller (GM) survey meter and other items. The Department went to Action Towing to investigate the radioactivity. In addition to the old military GM survey meter, which was not radioactive, the Department found two glass tubes containing radioactive material, which measured about 2 milliroentgen/hour on contact. One of the tubes was labeled as radium-226. The Department took the radioactive tubes for disposal, then surveyed the car and found no elevated radioactivity remaining in the car, and therefore released the car for unrestricted use."
WA State Item Number: WA240001
The following information was received from the Washington State Department of Health, Office of Radiation Protection (the Department) via email:
"Action Towing LLC transported a car to the Schnitzer Steel Industries scrap metal facility, and it triggered the scrap yard's radiation detectors. The scrap yard staff measured about 35 micro roentgen/hour on the outside of the car. Officials at Schnitzer Steel Industries contacted the Department which resulted in an evaluation of the concern and issuance of a DOT special permit so that the radioactive car could be returned to Action Towing LLC for proper handling.
"The Action Towing office manager was informed that the staff had seen some sort of radiation equipment in the car, so the Department requested pictures of the equipment. The pictures showed an old military Geiger-Mueller (GM) survey meter and other items. The Department went to Action Towing to investigate the radioactivity. In addition to the old military GM survey meter, which was not radioactive, the Department found two glass tubes containing radioactive material, which measured about 2 milliroentgen/hour on contact. One of the tubes was labeled as radium-226. The Department took the radioactive tubes for disposal, then surveyed the car and found no elevated radioactivity remaining in the car, and therefore released the car for unrestricted use."
WA State Item Number: WA240001
Power Reactor
Event Number: 57058
Facility: Quad Cities
Region: 3 State: IL
Unit: [2] [] []
RX Type: [1] GE-3,[2] GE-3
NRC Notified By: Tom Boyle
HQ OPS Officer: Thomas Herrity
Region: 3 State: IL
Unit: [2] [] []
RX Type: [1] GE-3,[2] GE-3
NRC Notified By: Tom Boyle
HQ OPS Officer: Thomas Herrity
Notification Date: 03/28/2024
Notification Time: 01:52 [ET]
Event Date: 03/27/2024
Event Time: 20:46 [CDT]
Last Update Date: 03/28/2024
Notification Time: 01:52 [ET]
Event Date: 03/27/2024
Event Time: 20:46 [CDT]
Last Update Date: 03/28/2024
Emergency Class: Non Emergency
10 CFR Section:
50.72(b)(3)(iv)(A) - Valid Specif Sys Actuation
10 CFR Section:
50.72(b)(3)(iv)(A) - Valid Specif Sys Actuation
Person (Organization):
Edwards, Rhex (R3DO)
Edwards, Rhex (R3DO)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 2 | N | N | 0 | Power Operation | 0 | Power Operation |
AUTOMATIC ACTUATION OF REACTOR PROTECTION SYSTEM
The following information was provided by the licensee via email:
"At 2046 [CDT] on 3/27/24 with the unit 2 in Mode 5 at 0% power, an actuation of the Reactor Protection System occurred during testing of the scram discharge volume. The cause of the Reactor Protection System actuation was leakage of water into the scram discharge volume causing a high level condition while drains were isolated for testing. The Reactor Protection System automatically actuated as designed when the high scram discharge volume signal was received. All rods were previously fully inserted and the Control Rod Drive system was shutdown. No rod movement occurred due to the actuation.
"This event is being reported in accordance with 10 CFR 50.72(b)(3)(iv)(A) as an event that results in a valid actuation of the Reactor Protection System.
"There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified."
The following information was provided by the licensee via email:
"At 2046 [CDT] on 3/27/24 with the unit 2 in Mode 5 at 0% power, an actuation of the Reactor Protection System occurred during testing of the scram discharge volume. The cause of the Reactor Protection System actuation was leakage of water into the scram discharge volume causing a high level condition while drains were isolated for testing. The Reactor Protection System automatically actuated as designed when the high scram discharge volume signal was received. All rods were previously fully inserted and the Control Rod Drive system was shutdown. No rod movement occurred due to the actuation.
"This event is being reported in accordance with 10 CFR 50.72(b)(3)(iv)(A) as an event that results in a valid actuation of the Reactor Protection System.
"There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified."
Agreement State
Event Number: 57052
Rep Org: Texas Dept of State Health Services
Licensee: Nondestructive & Visual Inspection LLC.
Region: 4
City: Carthage State: TX
County:
License #: L06162
Agreement: Y
Docket:
NRC Notified By: Art Tucker
HQ OPS Officer: Natalie Starfish
Licensee: Nondestructive & Visual Inspection LLC.
Region: 4
City: Carthage State: TX
County:
License #: L06162
Agreement: Y
Docket:
NRC Notified By: Art Tucker
HQ OPS Officer: Natalie Starfish
Notification Date: 03/26/2024
Notification Time: 14:15 [ET]
Event Date: 03/26/2024
Event Time: 00:00 [CDT]
Last Update Date: 03/26/2024
Notification Time: 14:15 [ET]
Event Date: 03/26/2024
Event Time: 00:00 [CDT]
Last Update Date: 03/26/2024
Emergency Class: Non Emergency
10 CFR Section:
Agreement State
10 CFR Section:
Agreement State
Person (Organization):
Kellar, Ray (R4DO)
NMSS_EVENTS_NOTIFICATION (EMAIL)
Kellar, Ray (R4DO)
NMSS_EVENTS_NOTIFICATION (EMAIL)
AGREEMENT STATE REPORT - DETACHED SOURCE
The following was received from the Texas Department of State Health Services (the Department) via phone and email:
"On March 26, 2024, the Department was notified by the licensee's radiation safety office (RSO) that earlier this day a radiography crew had a source disconnect while using a SPEC 150 exposure device. The device contained a 23 curie, iridium-192 source.
"The disconnect occurred on the first shot of the day. The RSO reported that the radiographers had completed set up for the first shot but had failed to properly connect the guide tube to the camera. When the radiographers cranked the source out and it hit the collimator, the guide tube popped loose from the camera. The radiographer immediately attempted to crank the source back into the camera but when the source reached the end of the guide tube the source pigtail disconnected from the drive cable.
"The radiographers set up new boundaries and contacted the RSO. An RSO from a nearby office responded to the location. The RSO was wearing a self-reading dosimeter (SRD), alarming rate meter, and TLD [thermoluminescent dosimeter] exposure badge. The RSO placed the camera on the source for shielding, attached the source back to the drive cable, and retracted the source into the camera. The responding RSO's SRD was reading off scale after retracting the source. The badge has been sent to the licensee's dosimetry processor for emergency processing.
"The licensee does not believe any individual exceeded any limit due to this event. Additional information will be provided as it is received in accordance with SA-300."
Texas Incident # 10095
The following was received from the Texas Department of State Health Services (the Department) via phone and email:
"On March 26, 2024, the Department was notified by the licensee's radiation safety office (RSO) that earlier this day a radiography crew had a source disconnect while using a SPEC 150 exposure device. The device contained a 23 curie, iridium-192 source.
"The disconnect occurred on the first shot of the day. The RSO reported that the radiographers had completed set up for the first shot but had failed to properly connect the guide tube to the camera. When the radiographers cranked the source out and it hit the collimator, the guide tube popped loose from the camera. The radiographer immediately attempted to crank the source back into the camera but when the source reached the end of the guide tube the source pigtail disconnected from the drive cable.
"The radiographers set up new boundaries and contacted the RSO. An RSO from a nearby office responded to the location. The RSO was wearing a self-reading dosimeter (SRD), alarming rate meter, and TLD [thermoluminescent dosimeter] exposure badge. The RSO placed the camera on the source for shielding, attached the source back to the drive cable, and retracted the source into the camera. The responding RSO's SRD was reading off scale after retracting the source. The badge has been sent to the licensee's dosimetry processor for emergency processing.
"The licensee does not believe any individual exceeded any limit due to this event. Additional information will be provided as it is received in accordance with SA-300."
Texas Incident # 10095
Agreement State
Event Number: 57054
Rep Org: Colorado Dept of Health
Licensee: Northern Colorado University
Region: 4
City: Greeley State: CO
County:
License #: GL000610
Agreement: Y
Docket:
NRC Notified By: Kathryn Kirk
HQ OPS Officer: Natalie Starfish
Licensee: Northern Colorado University
Region: 4
City: Greeley State: CO
County:
License #: GL000610
Agreement: Y
Docket:
NRC Notified By: Kathryn Kirk
HQ OPS Officer: Natalie Starfish
Notification Date: 03/26/2024
Notification Time: 17:51 [ET]
Event Date: 03/25/2024
Event Time: 00:00 [MDT]
Last Update Date: 03/26/2024
Notification Time: 17:51 [ET]
Event Date: 03/25/2024
Event Time: 00:00 [MDT]
Last Update Date: 03/26/2024
Emergency Class: Non Emergency
10 CFR Section:
Agreement State
10 CFR Section:
Agreement State
Person (Organization):
Kellar, Ray (R4DO)
NMSS_EVENTS_NOTIFICATION (EMAIL)
ILTAB, (EMAIL) (EMAIL)
Kellar, Ray (R4DO)
NMSS_EVENTS_NOTIFICATION (EMAIL)
ILTAB, (EMAIL) (EMAIL)
AGREEMENT STATE REPORT - LOST EXIT SIGNS
The following is a summary of information received from the Colorado Department of Public Health and Environment via email:
Three SRB Technologies exit signs, model SLXTU1GB10, containing 7.09 curies each of tritium (21.27 curies total) were determined to be lost.
Colorado event number CO240008
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
The following is a summary of information received from the Colorado Department of Public Health and Environment via email:
Three SRB Technologies exit signs, model SLXTU1GB10, containing 7.09 curies each of tritium (21.27 curies total) were determined to be lost.
Colorado event number CO240008
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
Agreement State
Event Number: 57055
Rep Org: Colorado Dept of Health
Licensee: First Bank - Vail
Region: 4
City: Vail State: CO
County:
License #: CO240007
Agreement: Y
Docket:
NRC Notified By: Kathryn Kirk
HQ OPS Officer: Natalie Starfish
Licensee: First Bank - Vail
Region: 4
City: Vail State: CO
County:
License #: CO240007
Agreement: Y
Docket:
NRC Notified By: Kathryn Kirk
HQ OPS Officer: Natalie Starfish
Notification Date: 03/26/2024
Notification Time: 18:00 [ET]
Event Date: 03/22/2024
Event Time: 00:00 [MDT]
Last Update Date: 03/26/2024
Notification Time: 18:00 [ET]
Event Date: 03/22/2024
Event Time: 00:00 [MDT]
Last Update Date: 03/26/2024
Emergency Class: Non Emergency
10 CFR Section:
Agreement State
10 CFR Section:
Agreement State
Person (Organization):
Kellar, Ray (R4DO)
NMSS_EVENTS_NOTIFICATION (EMAIL)
ILTAB, (EMAIL) (EMAIL)
Kellar, Ray (R4DO)
NMSS_EVENTS_NOTIFICATION (EMAIL)
ILTAB, (EMAIL) (EMAIL)
AGREEMENT STATE REPORT - LOST EXIT SIGNS
The following is a summary of information received from the Colorado Department of Public Health and Environment via email:
Seven Isolite Corporation exit signs, model 2040, containing 11.5 curies each, of tritium (80.5 curies total) were determined to be lost.
Colorado event number CO240007
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
The following is a summary of information received from the Colorado Department of Public Health and Environment via email:
Seven Isolite Corporation exit signs, model 2040, containing 11.5 curies each, of tritium (80.5 curies total) were determined to be lost.
Colorado event number CO240007
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