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{{#Wiki_filter:UNITED STATESNUCLEAR REGULATORY COMMISSIONOFFICE OF NUCLEAR MATERIAL SAFETY AND SAFEGUARDSWASHINGTON, D.C. 20555January 14, 1993NRC INFORMATION NOTICE NO. 93-05: LOCKING OF RADIOGRAPHY EXPOSUREDEVICES
{{#Wiki_filter:UNITED STATES NUCLEAR REGULATORY
 
COMMISSION
 
===OFFICE OF NUCLEAR MATERIAL SAFETY AND SAFEGUARDS===
WASHINGTON, D.C. 20555 January 14, 1993 NRC INFORMATION
 
NOTICE NO. 93-05: LOCKING OF RADIOGRAPHY
 
EXPOSURE DEVICES


==Addressees==
==Addressees==
:All Nuclear Regulatory Commission industrial radiography licensees
:
All Nuclear Regulatory
 
Commission
 
industrial
 
radiography
 
licensees


==Purpose==
==Purpose==
This information notice is intended to: (a) alert licensees that the lockingmechanisms on certain industrial radiography exposure devices can be lockedwith the sealed source in the exposed position; and (b) emphasize theimportance of ensuring that the source is secure in a shielded position beforemoving the device. We expect that licensees will review this notice,distribute it to responsible staff, and consider actions, if appropriate, toverify that the source is properly secured at the conclusion of radiographicoperations. However, suggestions contained in this notice do not constituteany new NRC requirements, and no written response is required.
This information
 
notice is intended to: (a) alert licensees
 
that the locking mechanisms
 
on certain industrial
 
radiography
 
exposure devices can be locked with the sealed source in the exposed position;  
and (b) emphasize
 
the importance
 
of ensuring that the source is secure in a shielded position before moving the device. We expect that licensees
 
will review this notice, distribute
 
it to responsible
 
staff, and consider actions, if appropriate, to verify that the source is properly secured at the conclusion
 
of radiographic
 
operations.
 
However, suggestions
 
contained
 
in this notice do not constitute
 
any new NRC requirements, and no written response is required.Description
 
of Circumstances
 
Case 1: A radiographer
 
was overexposed
 
in an incident involving
 
a disconnected
 
source when he failed to conduct a survey after each exposure.After investigating
 
the incident, it was discovered
 
that the radiographer
 
had approached
 
the device without a survey instrument, locked the device, disassembled
 
the source guide tube, and left the drive controls connected before moving the device from one location to another. The radiographer
 
had incorrectly
 
assumed that in locking the exposure device, he had secured the source in a shielded position.
 
In fact, the sealed source remained in the guide tube because the pigtail had disconnected
 
from the drive cable. The radiographer's
 
error was further compounded
 
when the drive cable was not removed before moving the device, which would have allowed him to identify the absence of the source pigtail within the shielded assembly.Case 2: A radiographer
 
was performing
 
radiographic
 
exposures
 
of welds on a series of pipelines
 
that were located approximately
 
6.1 meters (20 feet) above ground. The radiographer
 
used a 1.8-meter
 
(6-foot) guide tube with collimator
 
and a 7.6-meter
 
(25-foot)
control cable. The radiographer
 
hung the device from the pipeline to perform the work with the control cables hanging down to the ground. After an exposure, the radiographer
 
retracted
 
the source, placed the control cables on the ground, and used a hydraulic
 
lift to get to the camera.9301080120
L4'6 fD C fe -2?- 0A Ik Cct
 
IN 93-05 January 14, 1993 Because the camera was suspended
 
above the lift, the radiographer
 
had to move the camera to reach the locking mechanism.
 
He moved the camera by grasping the control cables with his right hand and locking the camera with his left hand. He continued
 
with his left hand to disconnect
 
the guide tube from the camera. At this point, he noticed that the sealed source was protruding
 
approximately
 
10 centimeters
 
(4 inches) from the camera port. (Note: His alarming ratemeter
 
did not sound because it was not turned on. This violation of 10 CFR 34.33, which can result in a civil penalty, is addressed
 
in Information
 
Notice 91-49: "Enforcement
 
of Safety Requirements
 
for Radiographers").
 
Reenactments
 
of the incident showed that when the radiographer
 
turned the device, the crank handle could drag on the ground, exposing the sealed source.The radiographer
 
was then able to lock the device over the drive cable, with the sealed source protruding
 
approximately
 
10 centimeters
 
(4 inches).Analysis of the locking mechanism
 
after the event did not identify any obvious defects with the mechanism.
 
Tests performed
 
showed that the device could still be locked with the source in the exposed position.NRC Evaluation:
The findings in both of these cases raised concern among NRC staff that, under certain conditions, radiographers
 
could have false confidence
 
in the locking mechanisms.
 
If exposure devices can lock when the source is outside of the shielded position, then radiographers
 
could incorrectly
 
believe that they are protected
 
from exposure when, in fact, the source is not in its fully shielded position.
 
We are also concerned
 
that exposure devices are moved while the drive cables are still connected.
 
To evaluate the effectiveness
 
of the locking mechanism
 
on radiography
 
exposure devices and to determine
 
whether radiographers
 
commonly move the devices with drive cables still connected, NRC inspectors
 
observed licensee equipment
 
tests and interviewed
 
radiography
 
personnel.
 
===From the data collected, we determined===
that a majority of exposure devices can be locked when the source is in a variety of positions, rather than only when the source pigtail is properly seated, with the source in the fully shielded position.
 
Many source pigtails include a "locking ball," designed to prevent the source from moving forward when the lock is engaged; however, our observations
 
show that some exposure devices may be locked both when the source is not fully retracted
 
and while the drive cable is seated under the locking pin, thereby circumventing
 
the locking-ball
 
feature. This may result in a source being positioned
 
where it is not fully shielded.Many radiographers
 
acknowledged
 
to NRC inspectors
 
that they often leave drive cables connected
 
when moving an exposure device from one location to another at temporary
 
job sites. In addition, some acknowledged
 
leaving the guide tube connected.
 
One licensee stated that this practice had resulted in a source being forced out of the exposure device while the device was carried to a new location at a temporary
 
job site. This licensee noted that the device was locked at the time, but the source had not been fully retracted
 
before locking the device.
 
Attachment
 
1 IN 93-05 January 14, 1993 LIST OF RECENTLY ISSUED NMSS INFORMATION
 
NOTICES Information
 
Date of Notice No. Subject Issuance Issued to 93-04 93-03 92-84 92-72 Investigation
 
and Re-porting of Misadministra- tions by the Radiation Safety Officer Recent Revision to 10 CFR Part 20 and Change of Implementa- tion Date to January 1, 1994 Release of Patients Treated with Temporary Implants Employee Training and Shipper Registra-tion Requirements
 
for Transporting
 
Radioactive
 
Materials Emergency
 
Response Information
 
Require-ments for Radioactive
 
===Material Shipments Uranium Hexafluoride===
Cylinders
 
-Deviations
 
in Coupling Welds Implementation
 
Date for the Revision to the EPA Manual of Protective
 
Action Guides and Pro-tective Actions for Nuclear Incidents Implementation
 
of the Deliberate
 
Misconduct
 
Rule 01/07/93 01/05/93 12/17/92 10/18/92 08/24/92 08/12/92 05/12/92 05/08/92 92-62 All U.S. Nuclear Regulatory
 
Commission
 
medical licensees.
 
All byproduct, source, and special nuclear material licensees.
 
All Nuclear Regulatory
 
Com-mission Medical Licensees.
 
===All U.S. Nuclear Regulatory===
Commission
 
Licensees.
 
===All U.S. Nuclear Regulatory===
Commission
 
Licensees.
 
All fuel cycle licensees.
 
All holders of OLs or CPs for nuclear power reactors, non-power
 
reactors and materials
 
licensees
 
author-ized to possess large quantities
 
of radioactive
 
material.All Nuclear Regulatory
 
Commission
 
Licensees.
 
92-58 92-38 92-37 Attachment
 
2 IN 93-05 January 14, 1993 LIST OF RECENTLY ISSUED NRC INFORMATION
 
NOTICES Information
 
Date of Notice No. Subject Issuance Issued to 93-04 93-03 93-02 Investigation
 
and Re-porting of Misadministra- tions by the Radiation Safety Officer Recent Revision to 10 CFR Part 20 and Change of Implementa- tion Date to January 1, 1994 Malfunction
 
of A Pres-surizer Code Safety Valve Accuracy of Motor-Operated Valve Diagnostic
 
Equipment
 
===Manufactures===
by Liberty Technologies
 
Unexpected
 
Restriction
 
to Thermal Growth of Reactor Coolant Piping Potential
 
Failures of Emergency
 
Core Cooling Systems Caused by Foreign Material Blockage 93-01 01/07/93 01/05/93 01/04/93 01/04/93 12/24/92 12/23/92 12/17/92 12/18/92 All U.S. Nuclear Regulatory
 
Commission
 
medical licensees.
 
All byproduct, source, and special nuclear material licensees.
 
All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for nuclear power reactors.All Nuclear Regulatory
 
Commission
 
Medical Licensees All holders of OLs or CPs for nuclear power reactors.92-86 92-85 92-84 Release of Patients Treated with Temporary Implants 88-23, Supp. 4 Potential
 
for Gas Binding of High-Pres- sure Safety Injection Pumps during A Design Basis Accident OL = Operating
 
License CP = Construction
 
Permit
 
K)IN 93-05 January 14, 1993 Discussion:
All licensees
 
are reminded of the importance
 
of ensuring that the sources used in radiography
 
exposure devices are properly secured and fully shielded before moving the device. Radiographic
 
exposure devices manufactured
 
and new equipment
 
acquired by licensees
 
after January 10, 1992, must meet new design requirements
 
in 10 CFR 34.20. These require that, among other safety features, the device must automatically
 
secure the source assembly when it is cranked back into the fully shielded position within the device. However, many radiographic
 
exposure devices currently
 
in use do not include the newer safety features, and licensees
 
are not required to use devices that comply with 10 CFR 34.20 requirements
 
until after January 10, 1996. Certaih radiogiraphv
 
exposure devices still in use today may be able to be locked with the source in the exposed position.Experience
 
has shown that when an older exposure device is in use, the locking mechanism
 
is not an indicator
 
that the source is fully retracted
 
and secured.The use of engineered
 
safety features, like the lock mechanism, MUST BE coupled with a proper survey (10 CFR 34.43) AND use of an alarm ratemeter (10 CFR 34.33), to prevent the unintentional
 
exposure of personnel.
 
Surveys must be sufficient
 
to detect a change in exposure readings taken at the source tube outlet, to determine
 
whether the source is fully retracted
 
to a shielded position (10 CFR 34.43). Alarm ratemeters
 
serve as an additional
 
warning method. Additionally, it is recommended
 
that radiographers
 
disassemble
 
the source guide tube, remove the drive controls, and install the safety plugs or covers, before moving the radiography
 
exposure device to another location.The failure to do so has been identified
 
as a contributing
 
factor in the unintended
 
exposure of personnel, as well as in incidents
 
where radiographers
 
failed to notice that the source was not retracted
 
into the device.Sealed sources for radiography
 
are capable of delivering
 
significant
 
exposures to radiography
 
personnel
 
and to members of the general public, when handled by individuals
 
who are inattentive
 
to radiation
 
safety procedures.
 
It is recommended
 
that all workers understand
 
the consequences
 
of improperly
 
handling radiographic
 
devices, and that workers be encouraged
 
to use necessary precautions
 
when working with these devices.
 
IN 93-05 January 14, 1993 No written response is required by this information
 
notice.questions
 
about this matter, please contact the appropriate
 
office or the personnel
 
listed below.If you have any NRC regional ( Richard E. Cunningham, Director Division Industrial
 
and Medical Nuclear Safety, NMSS Gary Shear, Region III (708) 790-5620 Technical
 
contacts: Charles Cain, Region IV (817) 860-8186 Scott Moore, NMSS (301) 504-2514 Attachments:.
 
1. List of Recently 2. List of Recently Issued NMSS Information
 
Notices Issued NRC Information
 
Notices
 
IN 93-05 January 14, 1993 No written response is required by this information
 
notice. If you have any questions
 
about this matter, please contact the appropriate
 
NRC regional office or the personnel
 
listed below.Richard E. Cunningham, Director Division Industrial
 
and Medical Nuclear Safety, NMSS Technical
 
contacts: Gary Shear, Region III (708) 790-5620 Charles Cain, Region IV (817) 860-8186 Scott Moore, NMSS (301) 504-2514 Attachments:
1. List of Recently 2. List of Recently Issued NMSS Information
 
Notices Issued NRC Information
 
Notices* = see Drevious concurrence
 
OFC IMOB I E NMSS I N IMOB EIMABe n NAME *SMoore/sm/11
*EKraus *CJones *JGlenn DATE 11/30/92 10/19/92 12/08/92 12/09/92 OFC SCDB I E IMOB IMOB l El IMNS IMNS NAME *CHaughney
 
*KRamsey *FCombs *JGreeves
 
*RECunningham
 
DATE 12/10/92 1 01/05/93 1 12/08/92 01/06/93 01/07/93 C: COVER E: COVER & ENCL.N: NO COPY OFFICIAL RECORD COPY: 93-05.IN DOCUMENT NAME:
IN 93-January , 1993 No written response is required by this information
 
notice. If you have any questions
 
about this matter, please contact the appropriate
 
NRC regional office or the personnel
 
listed below.Richard E. Cunningham, Director Division Industrial
 
and Medical Nuclear Safety, NMSS Technical
 
Contacts: Gary Shear, 708-790-562C
 
Region III Charles Cain, Region IV 817-860-8186 Scott Moore, NMSS 301-504-2514 Attachments:
1. List of Recently 2. List of Recently Issued NMSS Information
 
Notices Issued NRC Information
 
Notices* -caP nyVauiniiC
 
anlnlnrranra
 
-Fe F 9- y ... _OFC IMOB I E NMSS I Nj IMOB I E IMAB lNAME *SMoore/sm/l1
*EKraus *CJones *JGlenn nATr IllnQ/I2 1 1 12n iog 12/08/92 12/09/92 Unsu I II-IU ---v -S ~ ~ ~ ~ --r~OFC SCDB I E IMOB , IM0B I E IMNS _ NS NAME *CHaughney
 
KRamsey K 4 *FCombs y Aves ham DATE 12/10/92 I/ E 91q 3 ,f 12/8/92 I / ____ 3 I_ _ / __ __ a :_ I C: COVER E: COVER & LNCL.N: NU WLI OFFICIAL RECORD COPY: G:LOCKING.SWM
 
IN 92-December , 1992 No written response is required by this information
 
notice.questions


==Description of Circumstances==
about this matter, please contact the appropriate
Case 1: A radiographer was overexposed in an incident involving adisconnected source when he failed to conduct a survey after each exposure.After investigating the incident, it was discovered that the radiographer hadapproached the device without a survey instrument, locked the device,disassembled the source guide tube, and left the drive controls connectedbefore moving the device from one location to another. The radiographer hadincorrectly assumed that in locking the exposure device, he had secured thesource in a shielded position. In fact, the sealed source remained in theguide tube because the pigtail had disconnected from the drive cable. Theradiographer's error was further compounded when the drive cable was notremoved before moving the device, which would have allowed him to identify theabsence of the source pigtail within the shielded assembly.Case 2: A radiographer was performing radiographic exposures of welds on aseries of pipelines that were located approximately 6.1 meters (20 feet) aboveground. The radiographer used a 1.8-meter (6-foot) guide tube with collimatorand a 7.6-meter (25-foot) control cable. The radiographer hung the devicefrom the pipeline to perform the work with the control cables hanging down tothe ground. After an exposure, the radiographer retracted the source, placedthe control cables on the ground, and used a hydraulic lift to get to thecamera.9301080120 L4'6 fD C fe -2?- 0AIkCct


IN 93-05January 14, 1993 Because the camera was suspended above the lift, the radiographer had to movethe camera to reach the locking mechanism. He moved the camera by graspingthe control cables with his right hand and locking the camera with his lefthand. He continued with his left hand to disconnect the guide tube from thecamera. At this point, he noticed that the sealed source was protrudingapproximately 10 centimeters (4 inches) from the camera port. (Note: Hisalarming ratemeter did not sound because it was not turned on. This violationof 10 CFR 34.33, which can result in a civil penalty, is addressed inInformation Notice 91-49: "Enforcement of Safety Requirements forRadiographers").Reenactments of the incident showed that when the radiographer turned thedevice, the crank handle could drag on the ground, exposing the sealed source.The radiographer was then able to lock the device over the drive cable, withthe sealed source protruding approximately 10 centimeters (4 inches).Analysis of the locking mechanism after the event did not identify any obviousdefects with the mechanism. Tests performed showed that the device couldstill be locked with the source in the exposed position.NRC Evaluation:The findings in both of these cases raised concern among NRC staff that, undercertain conditions, radiographers could have false confidence in the lockingmechanisms. If exposure devices can lock when the source is outside of theshielded position, then radiographers could incorrectly believe that they areprotected from exposure when, in fact, the source is not in its fully shieldedposition. We are also concerned that exposure devices are moved while thedrive cables are still connected.To evaluate the effectiveness of the locking mechanism on radiography exposuredevices and to determine whether radiographers commonly move the devices withdrive cables still connected, NRC inspectors observed licensee equipment testsand interviewed radiography personnel. From the data collected, we determinedthat a majority of exposure devices can be locked when the source is in avariety of positions, rather than only when the source pigtail is properlyseated, with the source in the fully shielded position. Many source pigtailsinclude a "locking ball," designed to prevent the source from moving forwardwhen the lock is engaged; however, our observations show that some exposuredevices may be locked both when the source is not fully retracted and whilethe drive cable is seated under the locking pin, thereby circumventing thelocking-ball feature. This may result in a source being positioned where itis not fully shielded.Many radiographers acknowledged to NRC inspectors that they often leave drivecables connected when moving an exposure device from one location to anotherat temporary job sites. In addition, some acknowledged leaving the guide tubeconnected. One licensee stated that this practice had resulted in a sourcebeing forced out of the exposure device while the device was carried to a newlocation at a temporary job site. This licensee noted that the device waslocked at the time, but the source had not been fully retracted before lockingthe device.
office or the personnel


Attachment 1IN 93-05January 14, 1993 LIST OF RECENTLY ISSUEDNMSS INFORMATION NOTICESInformation Date ofNotice No. Subject Issuance Issued to93-0493-0392-8492-72Investigation and Re-porting of Misadministra-tions by the RadiationSafety OfficerRecent Revision to10 CFR Part 20 andChange of Implementa-tion Date toJanuary 1, 1994Release of PatientsTreated with TemporaryImplantsEmployee Trainingand Shipper Registra-tion Requirements forTransporting RadioactiveMaterialsEmergency ResponseInformation Require-ments for RadioactiveMaterial ShipmentsUranium HexafluorideCylinders -Deviationsin Coupling WeldsImplementation Date forthe Revision to the EPAManual of ProtectiveAction Guides and Pro-tective Actions forNuclear IncidentsImplementation of theDeliberate Misconduct Rule01/07/9301/05/9312/17/9210/18/9208/24/9208/12/9205/12/9205/08/9292-62All U.S. Nuclear RegulatoryCommission medicallicensees.All byproduct, source, andspecial nuclear materiallicensees.All Nuclear Regulatory Com-mission Medical Licensees.All U.S. Nuclear RegulatoryCommission Licensees.All U.S. Nuclear RegulatoryCommission Licensees.All fuel cycle licensees.All holders of OLs or CPsfor nuclear power reactors,non-power reactors andmaterials licensees author-ized to possess largequantities of radioactivematerial.All Nuclear RegulatoryCommission Licensees.92-5892-3892-37 Attachment 2IN 93-05January 14, 1993 LIST OF RECENTLY ISSUEDNRC INFORMATION NOTICESInformation Date ofNotice No. Subject Issuance Issued to93-0493-0393-02Investigation and Re-porting of Misadministra-tions by the RadiationSafety OfficerRecent Revision to10 CFR Part 20 andChange of Implementa-tion Date toJanuary 1, 1994Malfunction of A Pres-surizer Code SafetyValveAccuracy of Motor-Operated Valve DiagnosticEquipment Manufacturesby Liberty TechnologiesUnexpected Restrictionto Thermal Growth ofReactor Coolant PipingPotential Failures ofEmergency Core CoolingSystems Caused byForeign Material Blockage93-0101/07/9301/05/9301/04/9301/04/9312/24/9212/23/9212/17/9212/18/92All U.S. Nuclear RegulatoryCommission medicallicensees.All byproduct, source, andspecial nuclear materiallicensees.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor nuclear power reactors.All Nuclear RegulatoryCommission Medical LicenseesAll holders of OLs or CPsfor nuclear power reactors.92-8692-8592-84Release of PatientsTreated with TemporaryImplants88-23,Supp. 4Potential for GasBinding of High-Pres-sure Safety InjectionPumps during A DesignBasis AccidentOL = Operating LicenseCP = Construction Permit
listed below.If you have any NRC regional Richard E. Cunningham, Director Division Industrial


K)IN 93-05January 14, 1993 Discussion:All licensees are reminded of the importance of ensuring that the sources usedin radiography exposure devices are properly secured and fully shielded beforemoving the device. Radiographic exposure devices manufactured and newequipment acquired by licensees after January 10, 1992, must meet new designrequirements in 10 CFR 34.20. These require that, among other safetyfeatures, the device must automatically secure the source assembly when it iscranked back into the fully shielded position within the device. However,many radiographic exposure devices currently in use do not include the newersafety features, and licensees are not required to use devices that complywith 10 CFR 34.20 requirements until after January 10, 1996. Certaihradiogiraphv exposure devices still in use today may be able to be locked withthe source in the exposed position.Experience has shown that when an older exposure device is in use, the lockingmechanism is not an indicator that the source is fully retracted and secured.The use of engineered safety features, like the lock mechanism, MUST BEcoupled with a proper survey (10 CFR 34.43) AND use of an alarm ratemeter(10 CFR 34.33), to prevent the unintentional exposure of personnel. Surveysmust be sufficient to detect a change in exposure readings taken at the sourcetube outlet, to determine whether the source is fully retracted to a shieldedposition (10 CFR 34.43). Alarm ratemeters serve as an additional warningmethod. Additionally, it is recommended that radiographers disassemble thesource guide tube, remove the drive controls, and install the safety plugs orcovers, before moving the radiography exposure device to another location.The failure to do so has been identified as a contributing factor in theunintended exposure of personnel, as well as in incidents where radiographersfailed to notice that the source was not retracted into the device.Sealed sources for radiography are capable of delivering significant exposuresto radiography personnel and to members of the general public, when handled byindividuals who are inattentive to radiation safety procedures. It isrecommended that all workers understand the consequences of improperlyhandling radiographic devices, and that workers be encouraged to use necessaryprecautions when working with these devices.
and Medical Nuclear Safety, NMSS Technical


IN 93-05January 14, 993No written response is required by this information notice.questions about this matter, please contact the appropriateoffice or the personnel listed below.If you have anyNRC regional( Richard E. Cunningham, DirectorDivision Industrial andMedical Nuclear Safety, NMSSGary Shear, Region III(708) 790-5620Technical contacts:Charles Cain, Region IV(817) 860-8186Scott Moore, NMSS(301) 504-2514Attachments:.1. List of Recently2. List of RecentlyIssued NMSS Information NoticesIssued NRC Information Notices
Contacts:
Gary Shear, Region III 708-790-5620
\m Charles Cain, Region IV 817-860-8186 cott Moore, NMSS 01-504-2514 Attachments:
1. List of Recently Issued NHSS Information


IN 93-05January 14, 1993 :93-05.INDOCUMENT NAME:
Notices 2. List of Recently Issued NR nformation
IN 93-January , 1993 : G:LOCKING.SWM


IN 92-December , 1992 : G:LOCKING.SWM
Notices OFC HQ IEI M A INI -AIEI AB IA NAME ro I _I ______I____/_
I_____DATE ii /o30/92 10/19/92/A/ I/92\6 I,9I1/92 OFC SCDB IM Io IIi I MNS IMNS NAME CH ge KRamsey = Uo X xJGreeves


}}
===RECunninghim===
DATE It/la /92 j9/ /92 81I _2 /_/92 //92_C: COVER E: COVER & ENCL.N: NO COPY OFFICIAL RECORD COPY: G:LOCKING.SWM}}


{{Information notice-Nav}}
{{Information notice-Nav}}

Revision as of 13:53, 31 August 2018

Locking of Radiography Exposure Devices
ML031080041
Person / Time
Site: Beaver Valley, Millstone, Hatch, Monticello, Calvert Cliffs, Dresden, Davis Besse, Peach Bottom, Browns Ferry, Salem, Oconee, Mcguire, Nine Mile Point, Palisades, Palo Verde, Perry, Indian Point, Fermi, Kewaunee, Catawba, Harris, Wolf Creek, Saint Lucie, Point Beach, Oyster Creek, Watts Bar, Hope Creek, Grand Gulf, Cooper, Sequoyah, Byron, Pilgrim, Arkansas Nuclear, Three Mile Island, Braidwood, Susquehanna, Summer, Prairie Island, Columbia, Seabrook, Brunswick, Surry, Limerick, North Anna, Turkey Point, River Bend, Vermont Yankee, Crystal River, Haddam Neck, Ginna, Diablo Canyon, Callaway, Vogtle, Waterford, Duane Arnold, Farley, Robinson, Clinton, South Texas, San Onofre, Cook, Comanche Peak, Yankee Rowe, Maine Yankee, Quad Cities, Humboldt Bay, La Crosse, Big Rock Point, Rancho Seco, Zion, Midland, Bellefonte, Fort Calhoun, FitzPatrick, McGuire, LaSalle, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant  Entergy icon.png
Issue date: 01/14/1993
From: Cunningham R E
NRC/NMSS/IMNS
To:
References
FOIA/PA-2015-0150 IN-93-005, NUDOCS 9301080120
Download: ML031080041 (9)
v • d • e


UNITED STATES NUCLEAR REGULATORY

COMMISSION

OFFICE OF NUCLEAR MATERIAL SAFETY AND SAFEGUARDS

WASHINGTON, D.C. 20555 January 14, 1993 NRC INFORMATION

NOTICE NO. 93-05: LOCKING OF RADIOGRAPHY

EXPOSURE DEVICES

Addressees

All Nuclear Regulatory

Commission

industrial

radiography

licensees

Purpose

This information

notice is intended to: (a) alert licensees

that the locking mechanisms

on certain industrial

radiography

exposure devices can be locked with the sealed source in the exposed position;

and (b) emphasize

the importance

of ensuring that the source is secure in a shielded position before moving the device. We expect that licensees

will review this notice, distribute

it to responsible

staff, and consider actions, if appropriate, to verify that the source is properly secured at the conclusion

of radiographic

operations.

However, suggestions

contained

in this notice do not constitute

any new NRC requirements, and no written response is required.Description

of Circumstances

Case 1: A radiographer

was overexposed

in an incident involving

a disconnected

source when he failed to conduct a survey after each exposure.After investigating

the incident, it was discovered

that the radiographer

had approached

the device without a survey instrument, locked the device, disassembled

the source guide tube, and left the drive controls connected before moving the device from one location to another. The radiographer

had incorrectly

assumed that in locking the exposure device, he had secured the source in a shielded position.

In fact, the sealed source remained in the guide tube because the pigtail had disconnected

from the drive cable. The radiographer's

error was further compounded

when the drive cable was not removed before moving the device, which would have allowed him to identify the absence of the source pigtail within the shielded assembly.Case 2: A radiographer

was performing

radiographic

exposures

of welds on a series of pipelines

that were located approximately

6.1 meters (20 feet) above ground. The radiographer

used a 1.8-meter

(6-foot) guide tube with collimator

and a 7.6-meter

(25-foot)

control cable. The radiographer

hung the device from the pipeline to perform the work with the control cables hanging down to the ground. After an exposure, the radiographer

retracted

the source, placed the control cables on the ground, and used a hydraulic

lift to get to the camera.9301080120

L4'6 fD C fe -2?- 0A Ik Cct

IN 93-05 January 14, 1993 Because the camera was suspended

above the lift, the radiographer

had to move the camera to reach the locking mechanism.

He moved the camera by grasping the control cables with his right hand and locking the camera with his left hand. He continued

with his left hand to disconnect

the guide tube from the camera. At this point, he noticed that the sealed source was protruding

approximately

10 centimeters

(4 inches) from the camera port. (Note: His alarming ratemeter

did not sound because it was not turned on. This violation of 10 CFR 34.33, which can result in a civil penalty, is addressed

in Information

Notice 91-49: "Enforcement

of Safety Requirements

for Radiographers").

Reenactments

of the incident showed that when the radiographer

turned the device, the crank handle could drag on the ground, exposing the sealed source.The radiographer

was then able to lock the device over the drive cable, with the sealed source protruding

approximately

10 centimeters

(4 inches).Analysis of the locking mechanism

after the event did not identify any obvious defects with the mechanism.

Tests performed

showed that the device could still be locked with the source in the exposed position.NRC Evaluation:

The findings in both of these cases raised concern among NRC staff that, under certain conditions, radiographers

could have false confidence

in the locking mechanisms.

If exposure devices can lock when the source is outside of the shielded position, then radiographers

could incorrectly

believe that they are protected

from exposure when, in fact, the source is not in its fully shielded position.

We are also concerned

that exposure devices are moved while the drive cables are still connected.

To evaluate the effectiveness

of the locking mechanism

on radiography

exposure devices and to determine

whether radiographers

commonly move the devices with drive cables still connected, NRC inspectors

observed licensee equipment

tests and interviewed

radiography

personnel.

From the data collected, we determined

that a majority of exposure devices can be locked when the source is in a variety of positions, rather than only when the source pigtail is properly seated, with the source in the fully shielded position.

Many source pigtails include a "locking ball," designed to prevent the source from moving forward when the lock is engaged; however, our observations

show that some exposure devices may be locked both when the source is not fully retracted

and while the drive cable is seated under the locking pin, thereby circumventing

the locking-ball

feature. This may result in a source being positioned

where it is not fully shielded.Many radiographers

acknowledged

to NRC inspectors

that they often leave drive cables connected

when moving an exposure device from one location to another at temporary

job sites. In addition, some acknowledged

leaving the guide tube connected.

One licensee stated that this practice had resulted in a source being forced out of the exposure device while the device was carried to a new location at a temporary

job site. This licensee noted that the device was locked at the time, but the source had not been fully retracted

before locking the device.

Attachment

1 IN 93-05 January 14, 1993 LIST OF RECENTLY ISSUED NMSS INFORMATION

NOTICES Information

Date of Notice No. Subject Issuance Issued to 93-04 93-03 92-84 92-72 Investigation

and Re-porting of Misadministra- tions by the Radiation Safety Officer Recent Revision to 10 CFR Part 20 and Change of Implementa- tion Date to January 1, 1994 Release of Patients Treated with Temporary Implants Employee Training and Shipper Registra-tion Requirements

for Transporting

Radioactive

Materials Emergency

Response Information

Require-ments for Radioactive

Material Shipments Uranium Hexafluoride

Cylinders

-Deviations

in Coupling Welds Implementation

Date for the Revision to the EPA Manual of Protective

Action Guides and Pro-tective Actions for Nuclear Incidents Implementation

of the Deliberate

Misconduct

Rule 01/07/93 01/05/93 12/17/92 10/18/92 08/24/92 08/12/92 05/12/92 05/08/92 92-62 All U.S. Nuclear Regulatory

Commission

medical licensees.

All byproduct, source, and special nuclear material licensees.

All Nuclear Regulatory

Com-mission Medical Licensees.

All U.S. Nuclear Regulatory

Commission

Licensees.

All U.S. Nuclear Regulatory

Commission

Licensees.

All fuel cycle licensees.

All holders of OLs or CPs for nuclear power reactors, non-power

reactors and materials

licensees

author-ized to possess large quantities

of radioactive

material.All Nuclear Regulatory

Commission

Licensees.

92-58 92-38 92-37 Attachment

2 IN 93-05 January 14, 1993 LIST OF RECENTLY ISSUED NRC INFORMATION

NOTICES Information

Date of Notice No. Subject Issuance Issued to 93-04 93-03 93-02 Investigation

and Re-porting of Misadministra- tions by the Radiation Safety Officer Recent Revision to 10 CFR Part 20 and Change of Implementa- tion Date to January 1, 1994 Malfunction

of A Pres-surizer Code Safety Valve Accuracy of Motor-Operated Valve Diagnostic

Equipment

Manufactures

by Liberty Technologies

Unexpected

Restriction

to Thermal Growth of Reactor Coolant Piping Potential

Failures of Emergency

Core Cooling Systems Caused by Foreign Material Blockage 93-01 01/07/93 01/05/93 01/04/93 01/04/93 12/24/92 12/23/92 12/17/92 12/18/92 All U.S. Nuclear Regulatory

Commission

medical licensees.

All byproduct, source, and special nuclear material licensees.

All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for nuclear power reactors.All Nuclear Regulatory

Commission

Medical Licensees All holders of OLs or CPs for nuclear power reactors.92-86 92-85 92-84 Release of Patients Treated with Temporary Implants 88-23, Supp. 4 Potential

for Gas Binding of High-Pres- sure Safety Injection Pumps during A Design Basis Accident OL = Operating

License CP = Construction

Permit

K)IN 93-05 January 14, 1993 Discussion:

All licensees

are reminded of the importance

of ensuring that the sources used in radiography

exposure devices are properly secured and fully shielded before moving the device. Radiographic

exposure devices manufactured

and new equipment

acquired by licensees

after January 10, 1992, must meet new design requirements

in 10 CFR 34.20. These require that, among other safety features, the device must automatically

secure the source assembly when it is cranked back into the fully shielded position within the device. However, many radiographic

exposure devices currently

in use do not include the newer safety features, and licensees

are not required to use devices that comply with 10 CFR 34.20 requirements

until after January 10, 1996. Certaih radiogiraphv

exposure devices still in use today may be able to be locked with the source in the exposed position.Experience

has shown that when an older exposure device is in use, the locking mechanism

is not an indicator

that the source is fully retracted

and secured.The use of engineered

safety features, like the lock mechanism, MUST BE coupled with a proper survey (10 CFR 34.43) AND use of an alarm ratemeter (10 CFR 34.33), to prevent the unintentional

exposure of personnel.

Surveys must be sufficient

to detect a change in exposure readings taken at the source tube outlet, to determine

whether the source is fully retracted

to a shielded position (10 CFR 34.43). Alarm ratemeters

serve as an additional

warning method. Additionally, it is recommended

that radiographers

disassemble

the source guide tube, remove the drive controls, and install the safety plugs or covers, before moving the radiography

exposure device to another location.The failure to do so has been identified

as a contributing

factor in the unintended

exposure of personnel, as well as in incidents

where radiographers

failed to notice that the source was not retracted

into the device.Sealed sources for radiography

are capable of delivering

significant

exposures to radiography

personnel

and to members of the general public, when handled by individuals

who are inattentive

to radiation

safety procedures.

It is recommended

that all workers understand

the consequences

of improperly

handling radiographic

devices, and that workers be encouraged

to use necessary precautions

when working with these devices.

IN 93-05 January 14, 1993 No written response is required by this information

notice.questions

about this matter, please contact the appropriate

office or the personnel

listed below.If you have any NRC regional ( Richard E. Cunningham, Director Division Industrial

and Medical Nuclear Safety, NMSS Gary Shear, Region III (708) 790-5620 Technical

contacts: Charles Cain, Region IV (817) 860-8186 Scott Moore, NMSS (301) 504-2514 Attachments:.

1. List of Recently 2. List of Recently Issued NMSS Information

Notices Issued NRC Information

Notices

IN 93-05 January 14, 1993 No written response is required by this information

notice. If you have any questions

about this matter, please contact the appropriate

NRC regional office or the personnel

listed below.Richard E. Cunningham, Director Division Industrial

and Medical Nuclear Safety, NMSS Technical

contacts: Gary Shear, Region III (708) 790-5620 Charles Cain, Region IV (817) 860-8186 Scott Moore, NMSS (301) 504-2514 Attachments:

1. List of Recently 2. List of Recently Issued NMSS Information

Notices Issued NRC Information

Notices* = see Drevious concurrence

OFC IMOB I E NMSS I N IMOB EIMABe n NAME *SMoore/sm/11

  • EKraus *CJones *JGlenn DATE 11/30/92 10/19/92 12/08/92 12/09/92 OFC SCDB I E IMOB IMOB l El IMNS IMNS NAME *CHaughney
  • KRamsey *FCombs *JGreeves
  • RECunningham

DATE 12/10/92 1 01/05/93 1 12/08/92 01/06/93 01/07/93 C: COVER E: COVER & ENCL.N: NO COPY OFFICIAL RECORD COPY: 93-05.IN DOCUMENT NAME:

IN 93-January , 1993 No written response is required by this information

notice. If you have any questions

about this matter, please contact the appropriate

NRC regional office or the personnel

listed below.Richard E. Cunningham, Director Division Industrial

and Medical Nuclear Safety, NMSS Technical

Contacts: Gary Shear, 708-790-562C

Region III Charles Cain, Region IV 817-860-8186 Scott Moore, NMSS 301-504-2514 Attachments:

1. List of Recently 2. List of Recently Issued NMSS Information

Notices Issued NRC Information

Notices* -caP nyVauiniiC

anlnlnrranra

-Fe F 9- y ... _OFC IMOB I E NMSS I Nj IMOB I E IMAB lNAME *SMoore/sm/l1

  • EKraus *CJones *JGlenn nATr IllnQ/I2 1 1 12n iog 12/08/92 12/09/92 Unsu I II-IU ---v -S ~ ~ ~ ~ --r~OFC SCDB I E IMOB , IM0B I E IMNS _ NS NAME *CHaughney

KRamsey K 4 *FCombs y Aves ham DATE 12/10/92 I/ E 91q 3 ,f 12/8/92 I / ____ 3 I_ _ / __ __ a :_ I C: COVER E: COVER & LNCL.N: NU WLI OFFICIAL RECORD COPY: G:LOCKING.SWM

IN 92-December , 1992 No written response is required by this information

notice.questions

about this matter, please contact the appropriate

office or the personnel

listed below.If you have any NRC regional Richard E. Cunningham, Director Division Industrial

and Medical Nuclear Safety, NMSS Technical

Contacts:

Gary Shear, Region III 708-790-5620

\m Charles Cain, Region IV 817-860-8186 cott Moore, NMSS 01-504-2514 Attachments:

1. List of Recently Issued NHSS Information

Notices 2. List of Recently Issued NR nformation

Notices OFC HQ IEI M A INI -AIEI AB IA NAME ro I _I ______I____/_

I_____DATE ii /o30/92 10/19/92/A/ I/92\6 I,9I1/92 OFC SCDB IM Io IIi I MNS IMNS NAME CH ge KRamsey = Uo X xJGreeves

RECunninghim

DATE It/la /92 j9/ /92 81I _2 /_/92 //92_C: COVER E: COVER & ENCL.N: NO COPY OFFICIAL RECORD COPY: G:LOCKING.SWM


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