Information Notice No. 88-90: Unauthorized Removal of Industrial Nuclear Gauges
UNITED STATES
NUCLEAR REGULATORY COMMISSION
OFFICE OF NUCLEAR MATERIAL SAFETY AND SAFEGUARDS
WASHINGTON, D.C. 20555
November 22, 1988
Information Notice No. 88-90: UNAUTHORIZED REMOVAL OF INDUSTRIAL
NUCLEAR GAUGES
Addressees:
All Nuclear Regulatory Commission (NRC) licensees authorized to possess, use,
manufacture, or distribute industrial nuclear gauges.
Purpose:
This notice is provided to alert recipients to a potentially significant prob-
lem involving nuclear gauges. It is expected that recipients will review this
notice for applicability to their facilities, distribute it to responsible
radiation staff or authorized users, as appropriate, and consider actions to
preclude a similar problem from occurring at their facilities. Primarily,
this notice concerns the unauthorized removal of gauges, especially those
which are damaged and might be leaking radioactive material, and failure to
perform radiological surveys. This notice also serves as a reminder to
licensees that they need to maintain awareness of their license conditions and
realize the limits of their emergency response capabilities when faced with a
potentially serious radiological incident. However, suggestions contained in
this notice do not constitute any new NRC requirements, and no written
response is required.
Description of Circumstances:
Recently, an NRC industrial licensee who was authorized to use four cesium-137
gauges in manufacturing steel components reported to NRC that 25 tons of
molten steel spilled on and around the gauges during a manufacturing incident.
As the steel cooled and hardened, the four gauges' shutters were stuck in the
open "beam-on" position. The gauges were embedded in the spilled steel, and
initial surveys showed low radiation levels due to the shielding effect of the
spilled steel. However, the licensee failed to evaluate the gauges and
surrounding spilled steel for radioactive contamination. The licensee
contacted its Radi-ation Safety Officer (RSO) by telephone and, before his
arrival at the site, had used torches to cut away the steel embedding the
gauges. After two of the gauges were removed, the RSO notified NRC of the
incident. NRC instructed the RSO to perform a leak test for radioactive
contamination on the gauges. This test resulted in readings up to
45 milliroentgens per hour on the surface of the smears, which indicated
significant leakage of radioactive material. The sealed radiation sources and
shielding material inside one or more of the gauges had melted because of the
molten steel (approximately 3000�F).
8811160211
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November 22, 1988
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As a result, 15 licensee workers received minor external radioactive con-
tamination, confined mostly to their clothing. Multiple areas onsite were
significantly contaminated. An immediate emergency response effort by NRC,
the Department of Energy, and State agencies identified and controlled the
spread of contamination so that no offsite contamination occurred. No
personnel radiation exposures in excess of NRC limits were reported. The
licensee lost approximately two weeks of production while a licensed
contractor performed onsite decontamination and waste disposal preparation
activities.
Discussion:
Licensees authorized to possess and use sealed sources in industrial nuclear
gauges should be aware of their responsibilities to maintain compliance with
their license conditions and applicable NRC regulations (particularly 10 CFR
Section 20.105(b) and 10 CFR Section 20.201). In this case, the licensee was
permitted, under a license condition, to relocate the gauges from their
mounted locations only after the shutters had been closed and locked.
However, the licensee was not permitted to relocate the gauges with damaged
shutters. The licensee failed to make such surveys as were necessary to
assure radiation levels specified in 10 CFR Section 20.105(b) were not
exceeded while the slag, protective shielding, and steel support brackets were
being cut away. The licensee also failed to initiate leak-test surveys of the
gauges to determine whether radiation source integrity had been breached and
whether contamination of personnel and the environment existed.
Whenever a gauge containing radioactive material is involved in an incident or
damaged, the RSO and other knowledgeable personnel, such as any radiation
safety consultants, should be notified immediately. The licensee should not
perform any work that may spread radioactive contamination, in the area of the
gauge, until the gauge is checked for leaks. If the incident could result in
a significant or uncontrolled spread of contamination, or cause or threaten to
cause the situations described in 10 CFR Section 20.403, NRC should be
notified immediately at (202) 951-0550 (twenty-four hours per day).
In June 1984, NRC reminded all licensees authorized to use fixed gauges that
problems might occur with gauges located in high temperature or corrosive
environments. (See Attachment 1.) Licensees should examine the environment
in which their gauges are installed to ensure that the gauges are protected
against possible adverse situations such as excessive heat or corrosive
materials.
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November 22, 1988
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No specific action or written response is required by this information notice.
If you have any questions about this matter, please contact the appropriate
NRC regional office or this office.
Richard E. Cunningham, Director
Division of Industrial and
Medical Nuclear Safety
Office of Nuclear Material
Safety and Safeguards
Technical Contacts: G. M. McCann, RIII
(312) 790-5741
S. W. Moore, NMSS
(301) 492-0514
Attachments: 1. NRC letter dtd 6/13/84, "NRC Licensing
Requirements for Fixed Gauges"
2. List of Recently Issued NRC Information Notices
. Attachment 2
IN 88-90
November 22, 1988
Page 1 of 1
LIST OF RECENTLY ISSUED
NRC INFORMATION NOTICES
_____________________________________________________________________________
Information Date of
Notice No._____Subject_______________________Issuance_______Issued to________
88-89 Degradation of Kapton 11/21/88 All holders of OLs
Electrical Insulation or CPs for nuclear
power reactors.
88-88 Degradation of Westinghouse 11/16/88 All holders of OLs
ARD Relays or CPs for nuclear
power reactors.
88-87 Pump Wear and Foreign 11/16/88 All holders of OLs
Objects in Plant Piping or CPs for nuclear
Systems power reactors.
86-106, Feedwater Line Break 11/10/88 All holders of OLs
Supp. 3 or CPs for nuclear
power reactors.
88-86 Operating with Multiple 10/21/88 All holders of OLs
Grounds in Direct Current or CPs for nuclear
Distribution Systems power reactors.
88-85 Broken Retaining Block 10/14/88 All holders of OLs
Studs on Anchor Darling or CPs for nuclear
Check Valves power reactors.
88-84 Defective Motor Shaft 10/20/88 All holders of OLs
Keys in Limitorque Motor or CPs for nuclear
Actuators power reactors.
88-83 Inadequate Testing of Relay 10/19/88 All holders of OLs
Contacts in Safety-Related or CPs for nuclear
Logic Systems power reactors.
88-82 Torus Shells with Corrosion 10/14/88 All holders of OLs
and Degraded Coatings in or CPs for BWRs.
BWR Containments
88-81 Failure of Amp Window 10/7/88 All holders of OLs
Indent Kynar Splices or CPs for nuclear
and Thomas and Betts power, test, and
Nylon Wire Caps During research reactors.
Environmental Quali-
fication Testing
_____________________________________________________________________________
OL = Operating License
CP = Construction Permit
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