United States Nuclear Regulatory Commission - Protecting People and the Environment

Information Notice No. 88-90: Unauthorized Removal of Industrial Nuclear Gauges

                                  UNITED STATES
                          NUCLEAR REGULATORY COMMISSION
                             WASHINGTON, D.C.  20555

                                November 22, 1988

                                   NUCLEAR GAUGES


All Nuclear Regulatory Commission (NRC) licensees authorized to possess, use, 
manufacture, or distribute industrial nuclear gauges. 


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).  

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                                                            Page 2 of 3

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 


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 

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                                                            November 22, 1988 
                                                            Page 3 of 3 

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 
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                                                            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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