Information Notice 1993-05, Locking of Radiography Exposure Devices

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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
NRC/NMSS/IMNS
To:
References
FOIA/PA-2015-0150 IN-93-005, NUDOCS 9301080120
Download: ML031080041 (9)


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.

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

the camera to reach the locking mechanism. He moved the camera had to move

the control cables with his right hand and locking the camera by grasping

hand. He continued with his left hand to disconnect the guide with his left

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

approximately 10 centimeters (4 inches) from the camera port. protruding

alarming ratemeter did not sound because it was not turned on. (Note: His

of 10 CFR 34.33, which can result in a civil penalty, is addressed This violation

Information Notice 91-49: "Enforcement of Safety Requirements in

Radiographers"). for

Reenactments of the incident showed that when the radiographer

device, the crank handle could drag on the ground, exposing turned the

the

The radiographer was then able to lock the device over the drive sealed source.

the sealed source protruding approximately 10 centimeters (4 cable, with

inches).

Analysis of the locking mechanism after the event did not identify

defects with the mechanism. Tests performed showed that the any obvious

still be locked with the source in the exposed position. device could

NRC Evaluation:

The findings in both of these cases raised concern among NRC

certain conditions, radiographers could have false confidence staff that, under

mechanisms. If exposure devices can lock when the source is in the locking

shielded position, then radiographers could incorrectly believeoutside of the

protected from exposure when, in fact, the source is not in that they are

its

position. We are also concerned that exposure devices are moved fully shielded

drive cables are still connected. while the

To evaluate the effectiveness of the locking mechanism on

radiography exposure

devices and to determine whether radiographers commonly move

drive cables still connected, NRC inspectors observed licenseethe devices with

and interviewed radiography personnel. From the data collected,equipment tests

that a majority of exposure devices can be locked when the source we determined

variety of positions, rather than only when the source pigtail is in a

seated, with the source in the fully shielded position. Many is properly

include a "locking ball," designed to prevent the source from source pigtails

when the lock is engaged; however, our observations show that moving forward

devices may be locked both when the source is not fully retractedsome exposure

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

locking-ball feature. This may result in a source being positioned the

is not fully shielded. where it

Many radiographers acknowledged to NRC inspectors that they

often leave drive

cables connected when moving an exposure device from one location

at temporary job sites. In addition, some acknowledged leaving to another

connected. One licensee stated that this practice had resulted the guide tube

being forced out of the exposure device while the device was in a source

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

the device. before locking

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 Investigation and Re- 01/07/93 All U.S. Nuclear Regulatory

porting of Misadministra- Commission medical

tions by the Radiation licensees.

Safety Officer

93-03 Recent Revision to 01/05/93 All byproduct, source, and

10 CFR Part 20 and special nuclear material

Change of Implementa- licensees.

tion Date to

January 1, 1994

92-84 Release of Patients 12/17/92 All Nuclear Regulatory Com- Treated with Temporary mission Medical Licensees.

Implants

92-72 Employee Training 10/18/92 All U.S. Nuclear Regulatory

and Shipper Registra- Commission Licensees.

tion Requirements for

Transporting Radioactive

Materials

92-62 Emergency Response 08/24/92 All U.S. Nuclear Regulatory

Information Require- Commission Licensees.

ments for Radioactive

Material Shipments

92-58 Uranium Hexafluoride 08/12/92 All fuel cycle licensees.

Cylinders - Deviations

in Coupling Welds

92-38 Implementation Date for 05/12/92 All holders of OLs or CPs

the Revision to the EPA for nuclear power reactors, Manual of Protective non-power reactors and

Action Guides and Pro- materials licensees author- tective Actions for ized to possess large

Nuclear Incidents quantities of radioactive

material.

92-37 Implementation of the 05/08/92 All Nuclear Regulatory

Deliberate Misconduct Rule Commission Licensees.

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 Investigation and Re- 01/07/93 All U.S. Nuclear Regulatory

porting of Misadministra- Commission medical

tions by the Radiation licensees.

Safety Officer

93-03 Recent Revision to 01/05/93 All byproduct, source, and

10 CFR Part 20 and special nuclear material

Change of Implementa- licensees.

tion Date to

January 1, 1994

93-02 Malfunction of A Pres- 01/04/93 All holders of OLs or CPs

surizer Code Safety for nuclear power reactors.

Valve

93-01 Accuracy of Motor- 01/04/93 All holders of OLs or CPs

Operated Valve Diagnostic for nuclear power reactors.

Equipment Manufactures

by Liberty Technologies

92-86 Unexpected Restriction 12/24/92 All holders of OLs or CPs

to Thermal Growth of for nuclear power reactors.

Reactor Coolant Piping

92-85 Potential Failures of 12/23/92 All holders of OLs or CPs

Emergency Core Cooling for nuclear power reactors.

Systems Caused by

Foreign Material Blockage

92-84 Release of Patients 12/17/92 All Nuclear Regulatory

Treated with Temporary Commission Medical Licensees

Implants

88-23, Potential for Gas 12/18/92 All holders of OLs or CPs

Supp. 4 Binding of High-Pres- for nuclear power reactors.

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. 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 Issued NMSS Information Notices

2. List of Recently 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 Issued NMSS Information Notices

2. List of Recently 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:

DOCUMENT NAME: 93-05.IN

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, Region III

708-790-562C

Charles Cain, Region IV

817-860-8186 Scott Moore, NMSS

301-504-2514 Attachments:

1. List of Recently Issued NMSS Information Notices

2. List of Recently Issued NRC Information Notices

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12/08/92

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DATE 12/10/92 I/ 3 ,f

E 91q 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. 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

\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 I MNS

IIi IMNS

NAME CH ge KRamsey = xJGreeves

Uo X RECunninghim

DATE It/la /92 j9/ /92 81I /_/92 _2

//92_

C: COVER E: COVER & ENCL. N: NO COPY

OFFICIAL RECORD COPY: G:LOCKING.SWM