Potential Problems from the Use of Space Heaters

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

                                January 17, 1989

Information Notice No. 89-04:  POTENTIAL PROBLEMS FROM THE USE OF 
                                   SPACE HEATERS


All holders of operating licenses or construction permits for nuclear power 
reactors and test and research reactors.  


This information notice is being provided to alert addressees to potential 
problems from the use of space heaters.  It is expected that recipients will 
review the information for applicability to their facilities and consider 
actions, as appropriate, to avoid similar problems.  However, suggestions 
contained in this information notice do not constitute NRC requirements; 
therefore, no specific action or written response is required. 

Description of Circumstances:

On December 7, 1988, with the Fort Calhoun Station in cold shutdown and de--
fueled, an onsite release of toxic chlorine gas occurred.  The chlorine gas 
leaked from a chlorine gas cylinder when the fusible plug melted because of 
the proximity of a space heater. 

The licensee stores the chlorine gas cylinders, used in the purification 
process of Missouri River water for plant cooling systems, in a ventilated, 
enclosed room approximately 4 by 6 feet.  To keep the cylinders warm in prepa-
ration for use, a 13-kW heater was placed in the room.  It appears, based on 
the licensee's initial investigation, that the fusible plug became overheated 
because of the close proximity of the heater to the cylinder and melted.  The 
melting point of the plug is approximately 160�F.  The melted fusible plug 
initiated the release of the chlorine gas.  

The licensee detected the chlorine leak by the odor of chlorine gas in the 
area adjacent to the gas bottle storage room.  The area was immediately 

A total of 22 individuals affected by inhalation of the gas were transported 
to a hospital by the rescue squad.  The most severe effect on any individual 
was minor lung and nasal passage irritation.  All individuals have been 
released from the hospital.  

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                                                            January 17, 1989
                                                            Page 2 of 2

Licensee personnel removed the leaking cylinder from the storage room to a 
parking lot that was downwind of the plant.  The cylinder was kept in the 
parking lot until it completely depressurized.  No other problems were re-
ported after the cylinder was placed in the parking lot.  


The use of space heaters at plants during the winter months is a common prac-
tice.  However, the use of space heaters may not have been fully evaluated.  
It is important that licensees consider the following items before placing 
a space heater into service:  

1.   Fire hazards or combustibles in the area of the space heater.  

2.   Damage to or effect on the operability of equipment by the space heater.  

3.   Effect of accelerated aging on the environmental qualification of electri-
     cal equipment caused by the space heater. 

Recipients may wish to review their use of space heaters to preclude problems 
that could result from inadequate controls. 

No specific action or written response is required by this information notice.  
If you have any questions about this matter, please contact one of the 
technical contacts listed below or the Regional Administrator of the 
appropriate regional office.  

                                   Charles E. Rossi, Director 
                                   Division of Operational Events Assessment
                                   Office of Nuclear Reactor Regulation

Technical Contacts:  P. C. Wagner, RIV
                     (817) 860-8127

                     John Jankovich, NRR
                     (301) 492-1167

Attachment:  List of Recently Issued NRC Information Notices
..                                                            Attachment 
                                                            IN 89-04
                                                            January 17, 1989
                                                            Page 1 of 1

                             LIST OF RECENTLY ISSUED
                             NRC INFORMATION NOTICES
Information                                  Date of 
Notice No._____Subject_______________________Issuance_______Issued to________

89-03          Potential Electrical          1/11/89        All fuel cycle and
               Equipment Problems                           major nuclear 

89-02          Criminal Prosecution of       1/9/89         All holders of a
               Licensee's Former President                  U.S. NRC specific
               for Intentional Safety                       license.

88-23,         Potential for Gas Binding     1/5/89         All holders of OLs
Supp. 1        of High-Pressure Safety                      or CPs for PWRs.
               Injection Pumps During a
               Loss-of-Coolant Accident

89-01          Valve Body Erosion            1/4/89         All holders of OLs
                                                            or CPs for nuclear
                                                            power reactors.

88-46,         Licensee Report of Defective  12/30/88       All holders of OLs
Supp. 2        Refurbished Circuit Breakers                 or CPs for nuclear
                                                            power reactors.

88-101         Shipment of Contaminated      12/28/88       All holders of OLs
               Equipment between Nuclear                    or CPs for nuclear
               Power Stations                               power reactors.

88-100         Memorandum of Understanding   12/23/88       All major nuclear
               between NRC and OSHA                         materials licensees
               Relating to NRC-licensed                     and utilities 
               Facilities (53 FR 43950,                     holding CPs and 
               October 31, 1988)                            OLs. 

88-99          Detection and Monitoring      12/20/88       All holders of OLs
               of Sudden and/or Rapidly                     or CPs for PWRs.
               Increasing Primary-to-
               Secondary Leakage

88-98          Electrical Relay Degradation  12/19/88       All holders of OLs
               Caused by Oxidation of                       or CPs for nuclear
               Contact Surfaces                             power reactors.
OL = Operating License
CP = Construction Permit 

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