Transmitting NUREG/CR-0181 Concerning Barrier & Penetration Data Needed For Physical Security System Assessment (Generic Letter 78-21)

                                                              GL 78-21
                                UNITED STATES 
                        NUCLEAR REGULATORY COMMISSION 
                            WASHINGTON, D.C. 20555 

                                        July 18, 1978 

All Power Reactor Licensees and Applicants with Docketed Applications To
Construct or Operate a Power Reactor 


Gentlemen: 

This letter and enclosed NUREG/CR-0181 are being sent to all licensees
authorized to operate a nuclear power reactor and to all applicants with
applications for a license to operate or construct a power reactor. 

NUREG/CR-0181 provides basic barrier and penetration data needed for physical
security system assessment.  The data provided in the NUREG is being used by
NRC during the reactor safeguards review process. 

Additional copies of this document can be obtained from the National Technical
Information Service, Springfield, Virginia 22161, at current prices. 

                                      Sincerely, 



                                      James R. Miller, Assistant Director
                                        for Reactor Safeguards
                                      Division of Operating Reactors 

Enclosure:  
NUREG/CR-0181

cc Without enclosure:  
Service List 



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