Information Notice No. 92-32: Problems Identified with Emergency Ventilation Systems for Near-Site (Within 10 Miles) Emergency Operations Facilities and Technical Support Centers

                                UNITED STATES
                           WASHINGTON, D.C.  20555

                               April 29, 1992

                               VENTILATION SYSTEMS FOR NEAR-SITE (WITHIN 10 
                               MILES) EMERGENCY OPERATIONS FACILITIES AND 
                               TECHNICAL SUPPORT centerS


All holders of operating licenses or construction permits for nuclear power 


The U.S. Nuclear Regulatory Commission (NRC) is issuing this information 
notice to alert addressees to potential problems resulting from inadequate 
maintenance and testing of Emergency Operations Facility (EOF) and Technical 
Support Center (TSC) emergency ventilation systems.  These problems could 
result in a situation after an accident in which the EOF or TSC would not 
provide the level of protection to emergency workers that was intended.  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 are not 
NRC requirements; therefore, no specific action or written response is 

Description of Circumstances

Through routine inspection activities, the NRC has identified concerns with 
the operational readiness of EOF and TSC emergency ventilation systems.  The 
following are three examples of recent inspection results:  

1.   Brunswick, February 1991.  While observing a requested startup of the 
     emergency ventilation system for the EOF, the inspector noted that the 
     system was in poor material condition.  The inspector also noted the 
     licensee had not implemented procedures for operating, maintaining, or 
     functional testing of the system.  (Inspection 
     Report 50-325,324/91-03).

2.   Vogtle, May 1991.  During a demonstration of the EOF ventilation 
     system, the system failed to provide a positive pressure in the EOF in 
     the emergency mode.  After initial repair efforts, the system again 
     failed to initiate the emergency mode when required.  The licensee had 
     neither a maintenance program nor test and operating procedures for the 
     system.  (Inspection Reports 50-424,425/91-04 and 50-424,425/91-08). 


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3.   Crystal River, May 1991.  During an annual exercise, the TSC 
     ventilation system failed to maintain facility habitability after 
     approximately 2 hours of operation.  The facility was originally 
     designed for 29 persons assuming a heat load of 450 btu/hr per person.  
     A heat load assumption of 640 btu/hr per person for an approximate 70 
     persons occupancy level would have been more applicable.  The licensee 
     had neither operating procedures nor a maintenance and testing program 
     for the ventilation system.  (Inspection Report 50-302/91-08).


The NRC requires licensees and applicants to provide emergency facilities 
and equipment in support of operating nuclear power plants in the following 

1.   10 CFR 50.47, "Emergency Plans," Section (b)(8)

2.   10 CFR Part 50, Appendix E, Section IV.E, "Emergency Facilities and 

Guidance for implementing the requirements contained in the regulations is 
provided in NUREG-0737, Supplement 1, "Clarification of TMI Action Plan 
Requirements."  This NUREG document was transmitted to licensees via Generic 
Letter 82-33, "Supplement 1 to NUREG-0737 - Requirements for Emergency 
Response Capability," dated December 17, 1982.  It provides general design 
and performance criteria for EOF and TSC ventilation systems.  The NRC has 
not specifically identified maintenance and test criteria for these 
ventilation systems, but instead has provided a degree of flexibility within 
which licensees can exercise management prerogative in their maintenance 
programs.  Other documents that provide guidance on maintenance and test 
programs for ventilation systems, which many licensees have used as a basis 
for maintenance and test programs, are:

1.   Regulatory Guide 1.52, "Design, Test, and Maintenance Criteria for 
     Post-Accident Engineered-Safety-Feature Atmosphere Cleanup System Air 
     Filtration and Adsorption Units of Light-Water-Cooled Nuclear Power 

2.   Regulatory Guide 1.140, "Design, Test, and Maintenance Criteria for 
     Normal Ventilation Exhaust System Air Filtration and Adsorption Units 
     of Light-Water Cooled Nuclear Power Plants" 

3.   American Society of Mechanical Engineers (ASME) Standard N510, "Testing 
     of Nuclear Air Treatment Systems"

If dose assessment, communications, or decisionmaking capability is lost or 
impaired because the EOF and/or TSC become uninhabitable and are evacuated, 
the ability of the licensee's emergency response staff could be severely 
impaired, thus jeopardizing protection of the health and safety of the 


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This information notice requires no specific action or written response.  If 
you have any questions about the information in this notice, please contact 
one of the technical contacts listed below or the appropriate Office of 
Nuclear Reactor Regulation (NRR) project manager. 

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

Technical contacts:  Glen W. Salyers, RII
                     (404) 331-5604

                     Daniel M. Barss, NRR
                     (301) 504-2922

Attachment:  List of Recently Issued NRC Information Notices

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