Regulatory Guide 1.140: Difference between revisions

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{{Adams
{{Adams
| number = ML011710150
| number = ML16070A277
| issue date = 06/30/2001
| issue date = 08/31/2016
| title = (Revision 2), Design, Inspection, and Testing Criteria for Air Filtration and Adsorption Units of Normal Atmosphere Cleanup Systems in Light-Water-Cooled Nuclear Power Plants
| title = Design, Inspection, and Testing Criteria for Air Filtration and Adsorption Units of Normal Atmosphere Cleanup Systems in Light-Water-Cooled Nuclear Power Plants
| author name =  
| author name =  
| author affiliation = NRC/RES
| author affiliation = NRC/RES
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| docket =  
| docket =  
| license number =  
| license number =  
| contact person = Segala J
| contact person = Burton S
| case reference number = DG-1103
| case reference number = RG 1.140, Rev. 3
| document report number = RG-1.140
| document report number = DG-1280
| package number = ML16068A291
| document type = Regulatory Guide
| document type = Regulatory Guide
| page count = 17
| page count = 19
}}
}}
{{#Wiki_filter:U.S. NUCLEAR REGULATORY COMMISSION                                                                       Revision 2 June 2001 REGULATORY
{{#Wiki_filter:U.S. NUCLEAR REGULATORY COMMISSION  
                                    GUIDE
August 2016 OFFICE OF NUCLEAR REGULATORY RESEARCH  
                                    OFFICE OF NUCLEAR REGULATORY RESEARCH
Revision 3 REGULATORY GUIDE
                                              REGULATORY GUIDE 1.140
 
                                                            (Draft was issued as DG-1103)
Technical Lead Jerome Bettle
                  DESIGN, INSPECTION, AND TESTING CRITERIA FOR
 
              AIR FILTRATION AND ADSORPTION UNITS OF NORMAL
Written suggestions regarding this guide or development of new guides may be submitted through the NRCs public Web site under the Regulatory Guides document collection of the NRC Library at http://www.nrc.gov/reading-rm/doc-collections/reg-guides/contactus.html.
    ATMOSPHERE CLEANUP SYSTEMS IN LIGHT-WATER-COOLED
 
                                                NUCLEAR POWER PLANTS
Electronic copies of this RG, previous versions of this guide, and other recently issued guides are available through the NRCs public Web site under the Regulatory Guides document collection of the NRC Library at http://www.nrc.gov/reading-rm/doc-collections/. The regulatory guide is also available through the NRCs Agencywide Documents Access and Management System (ADAMS) at http://www.nrc.gov/reading-rm/adams.html, under ADAMS Accession No. ML16070A277. The regulatory analysis may be found in ADAMS under Accession No. ML16082A538 and the staff responses to the public comments on DG-1280 may be found under ADAMS
Accession No. ML16070A279.
 
REGULATORY GUIDE 1.140  
(Draft was issued as DG-1280, dated June 2012)  
 
DESIGN, INSPECTION, AND TESTING CRITERIA FOR AIR
FILTRATION AND ADSORPTION UNITS OF NORMAL  
ATMOSPHERE CLEANUP SYSTEMS IN  
LIGHT-WATER-COOLED NUCLEAR POWER PLANTS  


==A. INTRODUCTION==
==A. INTRODUCTION==
This guide provides guidance and criteria acceptable to the NRC staff for meeting the NRC's regulations with regard to the design, inspection, and testing of air filtration and adsorption units installed in the normal atmosphere cleanup systems of light-water-cooled nuclear power plants. This guide applies only to atmosphere cleanup systems designed to collect airborne radioactive materials during normal plant operation, including anticipated operational occurrences. Therefore, in this guide these systems are referred to as normal atmosphere cleanup systems. These normal atmosphere cleanup systems may consist of heaters and/or cooling coils, prefilters, high-efficiency particulate air (HEPA) filters, iodine adsorption units, fans, associated ductwork, dampers, and instrumentation. The instrumentation covered by this guide is that used to measure air flow and differential pressure.
Purpose This regulatory guide (RG) describes a method that the staff of the U.S. Nuclear Regulatory Commission (NRC) considers acceptable to implement regulatory requirements with regard to the design, inspection, and testing of normal atmosphere cleanup systems for controlling releases of airborne radioactive materials to the environment during normal operations, including anticipated operational occurrences. This guide applies to all types of nuclear power plants that use water as the primary means of cooling.


In Appendix A, "General Design Criteria for Nuclear Power Plants," to 10 CFR Part 50,
Applicability This RG applies to all holders of and applicants for operating licenses for nuclear power reactors under the provisions of Title 10 of the Code of Federal Regulations (10 CFR) Part 50, Domestic Licensing of Production and Utilization Facilities (Ref. 1), and all holders of and applicants for a power reactor combined license, standard design approval, or manufacturing license under 10 CFR Part 52, Licenses, Certifications, and Approvals for Nuclear Power Plants (Ref 2).
Domestic Licensing of Production and Utilization Facilities, General Design Criteria 60 and 61 require Regulatory guides are issued to describe and make available to the public such information as methods acceptable to the NRC staff for implementing specific parts of the NRCs regulations, techniques used by the staff in evaluating specific problems or postulated accidents, and data needed by the NRC staff in its review of applications for permits and licenses. Regulatory guides are not substitutes for regulations, and compliance with them is not required. Methods and solutions different from those set out in the guides will be acceptable if they provide a basis for the findings requisite to the issuance or continuance of a permit or license by the Commission.
Applicable Regulations
*
Title 10, of the Code of Federal Regulations, Part 50, Domestic Licensing of Production and Utilization Facilities (10 CFR Part 50) and the associated appendices establish the requirements and design criteria for atmospheric cleanup systems.


This guide was issued after consideration of comments received from the public. Comments and suggestions for improvements in these guides are encouraged at all times, and guides will be revised, as appropriate, to accommodate comments and to reflect new information or experience. Written comments may be submitted to the Rules and Directives Branch, ADM, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001.
o 10 CFR 50.34a and 50.36a, which relate to information that must be provided by applicants regarding how radioactive dose in effluents will be maintained as low as reasonably achievable (ALARA).  


Regulatory guides are issued in ten broad divisions: 1, Power Reactors; 2, Research and Test Reactors; 3, Fuels and Materials Facilities; 4, Environmental and Siting;
RG 1.140, Rev. 3, Page 2
5, Materials and Plant Protection; 6, Products; 7, Transportation; 8, Occupational Health; 9, Antitrust and Financial Review; and 10, General.


Single copies of regulatory guides (which may be reproduced) may be obtained free of charge by writing the Distribution Services Section, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by fax to (301)415-2289, or by email to DISTRIBUTION@NRC.GOV. Electronic copies of this guide are available on the internet at NRCs home page at <WWW.NRC.GOV> in the Reference Library under Regulatory Guides and through the Electronic Reading Room, as Accession Number ML011710150, along with other recently issued guides, at the same web site.
o 10 CFR Part 50, Appendix I, "Numerical Guides for Design Objectives and Limiting Conditions for Operation To Meet the Criterion As Low As Is Reasonably Achievable for Radioactive Material in Light-Water-Cooled Nuclear Power Reactor Effluents,"
which provides numerical guidance on design objectives for light-water-cooled nuclear power reactors to meet the requirements that radioactive material in effluents released to unrestricted areas be kept as low as is reasonably achievable.


that the nuclear power plant design include means to suitably control the release of radioactive materials in gaseous effluents during normal reactor operation, including anticipated operational occurrences and fuel storage and handling operations. In addition, 10 CFR 50.34a, "Design Objectives for Equipment To Control Releases of Radioactive Material in Effluents -- Nuclear Power Reactors," and 10 CFR 50.36a, "Technical Specifications on Effluents from Nuclear Power Reactors," of 10 CFR Part 50 require that means be employed to ensure that release of radioactive material to unrestricted areas during normal reactor operation, including during expected operational occurrences, is kept as low as is reasonably achievable.
*
10 CFR 20.1406, Minimization of contamination (Ref. 3), which requires licensees, to the extent practical, to conduct operations to minimize the introduction of residual radioactivity into the site, including the subsurface, and requires applicants to describe in their applications how facility design and procedures for operation will minimize, to the extent practicable, contamination of the facility and the environment, facilitate eventual decommissioning, and minimize, to the extent practicable, the generation of radioactive waste.


Appendix I, "Numerical Guides for Design Objectives and Limiting Conditions for Operation To Meet the Criterion As Low As Is Reasonably Achievable for Radioactive Material in Light-Water-Cooled Nuclear Power Reactor Effluents," to 10 CFR Part 50 provides guidance and numerical values for design objectives to help applicants for, and holders of, licenses for nuclear power plants meet the requirements of 10 CFR 50.34a and 50.36a. Appendix I requires that each light-water-cooled nuclear power reactor unit not exceed an annual dose design objective of 15 mrem to any organ of any individual in an unrestricted area via all exposure pathways from airborne radioactive iodine and particulate releases. Appendix I also requires that additional radwaste equipment be provided if the equipment has reasonably demonstrated technology and the cost-benefit ratio is favorable.
Related Guidance
*
Regulatory Guide 1.52, Design, Inspection, and Testing Criteria for Air Filtration and Adsorption Units of Post-Accident Engineered-Safety-Feature Atmosphere Cleanup Systems in Light-Water-Cooled Nuclear Power Plants (Ref. 4), provides guidance for the engineered safety feature (ESF) systems.


This guide does not apply to post-accident engineered-safety-feature (ESF) atmosphere cleanup systems that are designed to mitigate the consequences of postulated accidents.
*
RG 1.143, Design Guidance for Radioactive Waste Management Systems, Structures and Components Installed in Light-Water-Cooled Nuclear Reactor Power Plants (Ref. 5), describes systems handling of radioactive materials in liquids, gaseous and solid collection systems that include construction of structures.


Regulatory Guide 1.52, "Design, Inspection, and Testing Criteria for Air Filtration and Adsorption Units of Post-Accident Engineered-Safety-Feature Atmosphere Cleanup Systems in Light-Water- Cooled Nuclear Power Plants," provides guidance for these systems.
*
RG 4.21, Minimization of Contamination and Radioactive Waste Generation: Life Cycle Planning (Ref. 6), gives guidance for design of facilities to minimize contamination of the facility and the environment, and to minimize the generation of waste.


The guidance and criteria presented in this guide are not mandatory and licensees may choose not to change their licensing basis. Methods and solutions different from those set out in this guide will be acceptable when an applicant or licensee proposes an acceptable alternative method for complying with the specified portions of the NRCs regulations.
*
NUREG-0800 Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants: LWR Edition (Ref. 7), gives NRC review criteria for meeting the requirements of nuclear power plants.


The information collections contained in this regulatory guide are covered by the requirements of 10 CFR Part 50, which were approved by the Office of Management and Budget, approval number 3150-0011. If a means used to impose an information collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
Purpose of Regulatory Guides The NRC issues RGs to describe to the public methods that the staff considers acceptable for use in implementing specific parts of the agencys regulations, to explain techniques that the staff uses in evaluating specific problems or postulated accidents, and to provide guidance to applicants. Regulatory guides are not substitutes for regulations and compliance with them is not required. Methods and solutions that differ from those set forth in regulatory guides will be deemed acceptable if they provide a basis for the findings required for the issuance or continuance of a permit or license by the Commission.
 
Paper Reduction Act
 
This RG contains and references information collections covered by 10 CFR Parts 50 and 52 that are subject to the Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et seq.). These information collections were approved by the Office of Management and Budget (OMB), control numbers 3150-0011 and 3150-0151.
 
Public Protection Notification
 
RG 1.140, Rev. 3, Page 3
 
The NRC may not conduct or sponsor, and a person is not required to respond to, a request for information or an information collection requirement unless the requesting document displays a currently valid OMB control number.
 
RG 1.140, Rev. 3, Page 4


==B. DISCUSSION==
==B. DISCUSSION==
Particulate filtration and radioiodine adsorption units are included in the design of the normal atmosphere cleanup systems of light-water-cooled nuclear power plants to reduce the quantities of radioactive materials in gaseous effluents released from building or containment atmospheres during normal operation, including anticipated operational occurrence
Reason for Revision This revision of the guide (Revision 3) addresses changes to the referenced industry standards, which provide comprehensive test and inspection requirements. Specifically, this guide is revised to address changes to the referenced industry standards since the NRC issued Revision 2 of RG 1.140 in June 2001. The American Society of Mechanical Engineers (ASME) Committee on Nuclear Air and Gas Treatment (CONAGT) revised and expanded the scope of equipment covered by ASME-AG-1, Code on Nuclear Air and Gas Treatment (Ref. 8), which the staff previously endorsed in RG 1.140. The revision to ASME-AG-1b consolidated some requirements from ASME-N509, Nuclear Power Plant Air Cleaning Units and Components (Ref. 9); ASME-N510, Testing of Nuclear Air-Treatment Systems (Ref. 10);
and other documents previously endorsed by the staff in RG 1.140. In addition, CONAGT developed and published a new standard, ASME N511-2007, Inservice Testing of Nuclear Air Treatment, Heating Ventilation and Air Conditioning Systems (Ref. 11). 
Background
10 CFR Part 50, Domestic Licensing of Production and Utilization Facilities, Appendix A,
General Design Criteria for Nuclear Power Plants, General Design Criterion (GDC) 60, Control of Releases of Radioactive Materials to the Environment, requires in part, that a facilitys design include the means to control the release of radioactive materials in gaseous effluents. In addition, GDC 61, Fuel Storage and Handling and Radioactivity Control, requires in part, that fuel storage and handling, radioactive waste, and other systems which may contain radioactivity are designed with appropriate containment, confinement, and filtering systems. Title 10 CFR 50.34a, Design Objectives for Equipment To Control Releases of Radioactive Material in EffluentsNuclear Power Reactors, and 10 CFR 50.36a, Technical Specifications on Effluents from Nuclear Power Reactors, requires in part, that means be employed to ensure that the release of radioactive material to unrestricted areas during normal reactor operation, including during expected operational occurrences, is kept as low as reasonably achievable.
 
10 CFR 50.34a and 50.36a provide guidance and numerical values for design objectives to help applicants for new reactors and nuclear power plant license holders meet the requirements of 10 CFR Part
50, Appendix I, "Numerical Guides for Design Objectives and Limiting Conditions for Operation To Meet the Criterion As Low As Is Reasonably Achievable (ALARA) for Radioactive Material in Light- Water- Cooled Nuclear Power Reactor Effluents." In addition to complying with the design objectives and ALARA provisions, Section II.D of Appendix I requires that additional radwaste equipment of reasonably demonstrated technology be installed if it results in a reduction of population doses within a
50-mile (80-km) radius from the power plant when added to the system in order of diminishing favorable cost-benefit return. The requirements of this Paragraph D need not be complied with by persons who have filed applications for construction permits which were docketed on or after January 2, 1971, and prior to June 4, 1976, if the radwaste systems and equipment described in the preliminary or final safety analysis report and amendments satisfy the Guides on Design Objectives for Light-Water-Cooled Nuclear Power Reactors proposed in the Concluding Statement of Position of the Regulatory Staff in Docket-RM-50-2 dated February 20, 1974, pp. 25-30, reproduced in the Annex to this Appendix I.
 
The design of the normal atmosphere cleanup systems of light-water-cooled nuclear power plants includes particulate filtration and radioiodine adsorption units to reduce the quantities of radioactive materials in gaseous effluents released from primary containment or auxiliary building atmospheres during normal operations, including anticipated operational occurrences. These systems operate to meet the as low as reasonably achievable requirements of 10 CFR 50.34a and 10 CFR 50.36
 
====a. Auxiliary ====
 
RG 1.140, Rev. 3, Page 5
 
buildings can include those referred to as the secondary containment building, turbine building, radwaste building, and fuel handling building.


====s. All such====
Normal atmospheric cleanup systems are generally designed to operate continuously under normal environmental conditions, such as inlet radioiodine activity levels up to 37 millibecquerels per cubic centimeter (16.4 picocuries per cubic inch), relative humidity up to 100 percent, temperatures up to
                                                1.140-2
52 degrees Celsius (125 degrees Fahrenheit), and normal atmospheric pressure. System design, inspection, and testing anticipates the buildup of radioactive particulates and radioiodine and minimizes consequential degradation of system performance. The ambient environment both within and surrounding the facility may affect the performance of the normal atmosphere cleanup systems. Industrial contaminants and pollutants, as well as temperature and relative humidity, contribute to the aging and weathering of filters and adsorbers and reduce their reliability.


cleanup systems should be designed to operate continuously under normal environmental conditions.
Components of the normal atmosphere cleanup systems are designed for reliable performance under the expected operating conditions. Initial and inservice testing and proper maintenance are also primary factors in ensuring system reliability. Component and system design support and facilitate testing, inspection, and maintenance through built-in layout and accessibility features.


In this guide, cleanup systems that should operate to meet the "as low as is reasonably achievable (ALARA)" guidelines of Appendix I to 10 CFR Part 50 inside the primary containment (recirculating units) are designated as "primary systems." Primary systems generally include a containment cleanup system (kidney filtration system). Systems that operate outside the primary containment are designated as "secondary systems." Secondary systems generally include normal atmosphere cleanup systems servicing the reactor building, turbine building, radwaste building, auxiliary building, mechanical vacuum pump, main condenser air ejector, and any other release points that may contain particulate and gaseous radioiodine species.
Section FF of ASME AG-1b-2009, provides the terminology and describes the characteristics of adsorbent media.  The only adsorbent media discussed in this RG is impregnated activated carbon because it is used nearly to the exclusion of all others by NRC licensees.


These normal atmosphere cleanup systems should be able to withstand normal environmental conditions such as inlet concentrations of radioactive iodine up to 10-6 &#xb5;Ci/cm3, relative humidity of the influent stream up to 100%, temperatures of the influent stream up to
In addition to filtration systems used to treat exhausts from containment and auxiliary building atmospheres, cleanup systems are also used to treat process streams from power cycle waste offgas systems. These systems treat radioactive process and effluent streams characterized by the presence of noble gases, radioiodines, and mixtures of hydrogen and oxygen gases. These systems also operate to meet the as low as reasonably achievable requirements of 10 CFR 50.34a and 10 CFR 50.36a. The design of treatment systems used in power cycle waste offgas systems are characterized by the presence of hydrogen recombiners, compressors, delay tanks or vessels either empty or containing large amounts of activated carbon (e.g., hundreds of kilograms or thousands of pounds in PWRs or tens of thousands of kilograms/pounds in BWRs). 
125&deg;F (52&deg;C), and normal atmospheric pressure. The system should be designed, inspected, and tested in such a manner that radiation levels of airborne radioactive material and radioiodine buildup on the adsorber do not degrade the performance of the filter system or any component.
Harmonization with International Standards The International Atomic Energy Agency (IAEA) has established a series of safety guides and standards constituting a high level of safety for protecting people and the environment. IAEA safety guides present international good practices and increasingly reflects best practices to help users striving to achieve high levels of safety. Pertinent to this regulatory guide, IAEA Safety Guide NS-G-1.10, Design of Reactor Containment Systems for Nuclear Power Plants (Ref. 12), addresses the requirements of management of radionuclides leaking through a containment of Nuclear Power Plants. Additionally, IAEA Safety Guide NS-G-2.7, Radiation Protection and Radioactive Waste Management in the Operation of Nuclear Power Plants (Ref. 13), provides recommendations as to how to develop radiation protection programs. IAEA Safety Standard SSR-2/1, Safety of Nuclear Power Plants: Design (Ref. 14), addresses controlling the release of radioactive gases into the environment. The NRC has an interest in facilitating the harmonization of standards used domestically and internationally. This RG is consistent with the recommendations and guidance in the IAEA Safety Guides NS-G-1.10, NG-G-2.7 and SSR-2/1.


Normal atmosphere cleanup system heaters are designed to heat the influent stream to reduce its relative humidity before it reaches the filters and adsorbers. HEPA filters are installed to remove particulate matter, which may be radioactive, and pass the air stream to the adsorber, which then removes gaseous iodine (elemental iodine and organic iodides) from the air stream. A
RG 1.140, Rev. 3, Page 6
HEPA filter or a medium efficiency postfilter (as defined in Section 5.3 of ASME N509-1989 (Ref. 1)) downstream from the adsorption units collects carbon fines and provides additional protection against particulate matter release in case of failure of the upstream HEPA filter bank. It is not necessary to perform in-place leak testing on postfilters or HEPA filters downstream from the carbon adsorbers. It is advantageous for the postfilters or HEPA filters downstream from the carbon adsorbers to be installed in separate housings or to be removed from the housing (for systems with a fan downstream from the housing) during in-place leak testing of the upstream HEPA filter. This will contribute to the accuracy of the test results for the upstream HEPA filter.


The arrangement of the ductwork and the transitions between the separate housings can provide a torturous path that will aid in mixing the challenge agent. Removing the filters downstream from the carbon adsorbers will permit sampling downstream from the fan. The fan will provide the necessary mixing for an accurate test and the absences of the postfilters or HEPA filters downstream from the carbon adsorbers will prevent the challenge aerosol from being removed from the air stream. The fan is the final item in a normal atmosphere cleanup system.
Documents Discussed in Staff Regulatory Guidance


Consideration should be given to installing prefilters upstream from the HEPA filters to reduce the particulate load and extend their service life.
This RG endorses the use of one or more codes or standards developed by external organizations, and other third party guidance documents. These codes, standards and third party guidance documents may contain references to other codes, standards or third party guidance documents (secondary references). If a secondary reference has itself been incorporated by reference into NRC regulations as a requirement, then licensees and applicants must comply with that standard as set forth in the regulation. If the secondary reference has been endorsed in a RG as an acceptable approach for meeting an NRC
requirement, then the standard constitutes a method acceptable to the NRC staff for meeting that regulatory requirement as described in the specific RG. If the secondary reference has neither been incorporated by reference into NRC regulations nor endorsed in a RG, then the secondary reference is neither a legally-binding requirement nor a generic NRC approved acceptable approach for meeting an NRC requirement. However, licensees and applicants may consider and use the information in the secondary reference, if appropriately justified, consistent with current regulatory practice, and consistent with applicable NRC requirements.


The environmental history of the facility will affect the performance of the normal atmosphere cleanup system. Industrial contaminants, pollutants, temperature, and relative humidity contribute to the aging and weathering of filters and adsorbers and reduce their capability to perform their intended functions. Therefore, aging, weathering, and poisoning of these components, which may vary from site to site, need to be considered during design and operation.
RG 1.140, Rev. 3, Page 7


1.140-3
C. STAFF REGULATORY GUIDANCE
This section describes the methods and approves for use industry guidance, with clarifications or exceptions, which the NRC staff considers acceptable to implement regulatory requirements with regard to the design, inspection, and testing of normal atmosphere cleanup systems for controlling releases of airborne radioactive materials to the environment during normal operations, including anticipated operational occurrences.


Average temperature and relative humidity also vary from site to site, and the potential buildup of moisture in the adsorber warrants equal design consideration. The effects of these factors on the normal atmosphere cleanup system can be determined by a monitoring program.
1.


All components of the normal atmosphere cleanup system need to be designed for reliable performance under the expected operating conditions. Initial testing and proper maintenance are primary factors in ensuring the reliability of the system. Consideration during the design phase of problems of system maintenance can contribute significantly to the reliability of the system by increasing the ease of such maintenance. A layout that provides accessibility and sufficient working space to safely and efficiently perform the required maintenance functions is of particular importance in the design. Periodic inspection and testing during operation to verify the efficiency of the components is another important means of ensuring reliability. Built-in features that will facilitate convenient in-place testing are important in system design.
General Design and Testing Criteria American Society of Mechanical Engineers code, ASME AG-1-2009, including 2010 Addenda
1a and 2011 Addenda 1b (i.e., ASME AG-1b-2009), and ASME N511-2007, provides guidance that is acceptable to the NRC staff for the design, construction, acceptance testing, quality assurance, and inservice testing of normal atmosphere cleanup systems and components. Normal atmosphere cleanup systems designed to ASME N509-2002 (Reaffirmed 2008), (or its earlier versions), and tested to ASME
N510-2007, (or its earlier versions), are also considered adequate to protect public health and safety.


Standards acceptable to the NRC staff for the design and testing of normal atmosphere cleanup systems include those portions of ASME N509-1989, "Nuclear Power Plant Air-Cleaning Units and Components" (Ref. 1), ASME N510-1989, "Testing of Nuclear Air-Treatment Systems"
2.
(Ref. 2), and ASME AG-1-1997, "Code on Nuclear Air and Gas Treatment" (Ref. 3) that are referenced in this guide and ASTM D3803-1989, "Standard Test Methods for Nuclear-Grade Activated Carbon" (Ref. 4).
        If a referenced standard has been incorporated separately into the NRCs regulations, licensees and applicants must comply with that standard as set forth in the regulation. If the referenced standard has been endorsed in a regulatory guide, the standard constitutes a method acceptable to the NRC staff for meeting a regulatory requirement as described in the regulatory guide. If a referenced standard has been neither incorporated into the NRCs regulations nor endorsed in a regulatory guide, licensees and applicants may consider and use the information in the referenced standard if appropriately justified, consistent with current regulatory practice.


==C. REGULATORY POSITION==
Environmental Design Criteria a.
1.      GENERAL DESIGN AND TESTING CRITERIA
        ASME AG-1-1997, Code on Nuclear Air and Gas Treatment (Ref. 3), and ASME N509-
1989, Nuclear Power Plant Air-Cleaning Units and Components (Ref. 1) provide guidance that is acceptable to the NRC staff for the performance, design, construction, acceptance testing, and quality assurance of equipment used as components in nuclear safety-related or ESF air and gas treatment systems in nuclear power plants. Normal atmosphere cleanup systems designed to ASME N509-1989 (Ref. 1) (or its earlier versions) and tested to ASME N510-1989 (Ref. 2) (or its earlier versions) are considered adequate to protect public health and safety.


1.140-4
Design of normal atmosphere cleanup systems should be based on the anticipated range of operating parameters of temperature, pressure, relative humidity, and radiation levels during normal plant operations, including anticipated operational occurrences.


2.      ENVIRONMENTAL DESIGN CRITERIA
b.
        2.1.    The design of each normal atmosphere cleanup system should be based on the anticipated range of operating parameters of temperature, pressure, relative humidity, and radiation levels during normal plant operations, including anticipated operational occurrences.


2.2.    If the normal atmosphere cleanup system is located in an area of high radiation during normal plant operation, adequate shielding of components and personnel from the radiation source should be provided.
Normal atmosphere cleanup system operation should not degrade the operation or capability of any safety system required to operate after a design-basis accident.


2.3.    The operation of any normal atmosphere cleanup system should not degrade the expected operation of any ESF system that is required to operate after a design basis accident.
c.


2.4.    The design of the normal atmosphere cleanup system should consider any sig- nificant contaminants such as dusts, chemicals, excessive moisture, or other particulate matter that could degrade the cleanup system's operation.
Design of normal atmosphere cleanup systems should consider any reasonably expected significant contaminants, such as chemicals, dusts, or other particulate matter that could degrade the systems operation or capability.


3.      SYSTEM DESIGN CRITERIA
d.
        Normal atmosphere cleanup systems should be designed in accordance with Section 4.0 of ASME N509-1989 (Ref. 1) and ASME AG-1-1997 (Ref. 3) as modified and supplemented by the following:
        3.1.    Normal atmosphere cleanup systems need not be redundant nor designed to Seismic Category I classification, but they should consist of at least the following components: (1) HEPA
filters before the adsorbers, (2) iodine adsorbers (impregnated activated carbon), (3) fans, and (4)
interspersed ducts, dampers, and related instrumentation. To reduce the particulate load on the HEPA filters and extend their service life, the installation of prefilters upstream from the initial HEPA section is suggested. Consideration should also be given to the installation of a HEPA filter or medium efficiency postfilter (as defined in Section 5.3 of ASME N509-1989 (Ref. 1))
downstream from carbon adsorbers to retain carbon fines. Heaters or cooling coils or both may be used when the humidity is to be controlled before filtration. Whenever a normal atmosphere cleanup system is designed to remove only particulate matter, a component for iodine adsorption need not be included.


3.2.    To ensure reliable in-place testing, the volumetric air-flow rate of a single cleanup unit should be limited to approximately 30,000 cubic feet per minute. If a total system air flow in excess of this rate is required, multiple units should be used.
For power cycle waste offgas systems relying on activated carbon delay tanks or beds, the above environmental design criteria are deemed applicable, but should be evaluated and applied taking into consideration the systems specific design features.


3.3.    Each normal atmosphere cleanup system should be instrumented to monitor and alarm pertinent pressure drops and flow rates in accordance with the recommendations of Section
3.
5.6 of ERDA 76-21 (Ref. 5) and Section 4.9 of ASME N509-1989 (Ref. 1).
                                                1.140-5


3.4.    To maintain the radiation exposure to operating and maintenance personnel as low as is reasonably achievable (ALARA), normal atmosphere cleanup systems and components should be designed to control leakage and facilitate maintenance, inspection, and testing in accordance with the guidance in Regulatory Guide 8.8, "Information Relevant to Ensuring that Occupational Radiation Exposures at Nuclear Power Stations Will Be As Low As Is Reasonable Achievable" (Ref. 6).
System Design Criteria
        3.5.    Outdoor air intake openings should be equipped with louvers, grills, screens, or similar protective devices to minimize the effects of high winds, rain, snow, ice, trash, and other contaminants on the operation of the system. The outdoor air intake openings should be located to minimize the effects of possible onsite plant contaminants, such as the diesel generator exhaust. If the atmosphere surrounding the plant could contain significant environmental contaminants, such as dusts and residues from smoke-cleanup systems from adjacent coal-burning power plants or industry, or is a salty environment near an ocean, the design of the system should consider these contaminants and prevent them from affecting the operation of any normal atmosphere cleanup system.


3.6.    Normal atmosphere cleanup system housings and ductwork should be designed to exhibit, on test, a maximum total leakage rate as defined in Article SA-4500 of ASME AG-1-1997 (Ref. 3). Duct and housing leak tests should be performed in accordance with Section TA of ASME AG-1-1997.
Normal atmospheric cleanup systems should be designed in accordance with ASME AG-1b-2009 as modified and supplemented by the following:
a.


4.      COMPONENT DESIGN CRITERIA AND QUALIFICATION TESTING
Normal atmosphere cleanup systems need not be redundant or designed to seismic Category I requirements, but they should consist of at least the following components:
        Components of normal atmosphere cleanup systems should be designed, constructed, and tested in accordance with Division II of ASME AG-1-1997 (Ref. 3), as modified and supplemented by the following.
(1)
high-efficiency particulate air (HEPA) filters upstream of adsorbers;


4.1.    Prefilters that are used in the normal atmosphere cleanup system should be designed, constructed, and tested in accordance with Section FB of ASME AG-1-1997.
(2)
iodine adsorbers (typically impregnated activated carbon), if iodine removal from the airstream is anticipated;


4.2.    Air heaters should be designed, constructed, and tested in accordance with Section CA of ASME AG-1-1997.
(3)
fans;


4.3.    The HEPA filters should be designed, constructed, and tested in accordance with Section FC of ASME AG-1-1997. Each HEPA filter should be tested for penetration of a challenge aerosol such as dioctyl phthalate (DOP) in accordance with Section TA of ASME AG-1-
(4)
1997.
interspersed ducts, dampers, and instrumentation;


4.4.    The HEPA filter and Type II adsorber cell mounting frames should be designed and constructed in accordance with Section FG of ASME AG-1-1997.
RG 1.140, Rev. 3, Page 8


4.5.    Filter and adsorber sections should be arranged in accordance with Section 4.4 of ERDA 76-21 (Ref. 5) and Section HA, Housings, of ASME AG-1a-2000 (Ref. 7).
(5)  
                                                  1.140-6
prefilters upstream of HEPA filters, if needed to reduce particulate loading of the HEPA filters and achieve an acceptable service life;


4.6.    System filter housings, including floors and doors, and electrical conduits, drains, and piping installed inside filter housings should be designed and constructed in accordance with Section 5.6 of ASME N509-1989 (Ref. 1) and Section HA, ASME AG-1a-2000 (Ref. 7).
(6)  
          4.7.    Adsorption units function efficiently at a relative humidity of 70% or less. If the relative humidity of the atmosphere entering the air cleanup system is expected to be greater than
postfilters downstream of adsorbers, if needed to retain carbon fines; and  
70% during normal reactor operation, heaters or cooling coils should be designed to reduce the relative humidity of the atmosphere entering the adsorption unit to 70% or less. Heaters should be designed, constructed, and tested in accordance with Section CA of ASME AG-1-1997 (Ref. 3)
exclusive of sizing criteria.


4.8.    Adsorber cells should be designed, constructed, and tested in accordance with Section FD for Type II Adsorber cells or Section FE for Type III Adsorber cells of ASME AG-1-
(7)
1997.
heating elements or cooling coils, or both, if necessary to control humidity before filtration.


The design of the adsorber section should consider possible iodine desorption and adsorbent auto-ignition that may result from radioactivity-induced heat in the adsorbent and concomitant temperature rise. Acceptable designs include a low-flow air bleed system, cooling coils, water sprays for the adsorber section, or other cooling mechanisms.
b.


When a water-based fire suppression or prevention (cooling) system is installed in the normal atmosphere cleanup system housing, the fire system should be manually actuated unless there is a reasonable probability that the iodine desorption and adsorbent auto-ignition could occur in the housing, in which case the fire system should have both automatic and manual actuation.
The volumetric airflow rate of a single filtration unit should be limited to 850 cubic meters (30,000 cubic feet) per minute unless reliable in-place testing can be assured. If a higher flow capacity is needed, consider a system design with multiple, parallel units.


The fire system should use open spray nozzles or devices of sufficient size, number, and location to provide complete coverage over the entire surface of the combustible filter media. The fire system should be hard piped and supplied with a reliable source of water at adequate pressure and volume. The location of the manual release (or valve) for the fire system should be remote from the cleanup system housing and should be consistent with the ALARA guidance in Regulatory Guide 8.8 (Ref. 6). Automatic fire systems should include a reliable means of detection to actuate the system. Detection can be accomplished by a mechanical or electrical device including, but not limited to, thermal, carbon monoxide, or smoke. Cross-zoning of detectors is acceptable. Manual fire systems should include a reliable means of internal monitoring for determining when to manually actuate the fire systems. The monitoring indication should be remote from the cleanup system housing in accordance with ALARA practices.
c.


4.9.    The adsorber section of the normal atmosphere cleanup system may contain any adsorbent material demonstrated to remove gaseous iodine (elemental iodine and organic iodides)
Normal atmosphere cleanup systems should be provided with instrumentation recommended in Section IA of ASME AG-1b-2009 for monitoring and alarming pertinent airflow rates and pressure drops.
from air at the required efficiency. However, since impregnated activated carbon1 is used almost exclusively, only impregnated activated carbon is discussed in this guide.


1 Activated carbon is typically impregnated with a chemical compound or compounds to enhance radioiodine retention, particularly under conditions of high temperatures and humidity. Typical impregnants include iodides such as potassium iodide and triiodide, amines such as triethylenediamine (TEDA), and combinations thereof.
d.


1.140-7
Normal atmosphere cleanup systems design should limit personnel radiation exposure by incorporation of features that facilitate inspection, testing, and maintenance consistent with the guidance of RG 8.8, Information Relevant to Ensuring that Occupational Radiation Exposures at Nuclear Power Stations Will Be As Low As Is Reasonably Achievable (Ref. 15).
e.


Each original or replacement batch or lot of impregnated activated carbon used in the adsorber section should meet Section FF of ASME AG-1-1997 (Ref. 3).2,3 A test performed as a
Outdoor air intake openings should be equipped with louvers, grills, screens, or similar protective devices to minimize the adverse effects of high winds, rain, snow, ice, and other debris on system operation. Outdoor air intake openings should be located to minimize the effects of onsite sources of contaminants, such as diesel generator exhaust.
"qualification test" should be interpreted to mean a test that establishes the suitability of a manufacturer's product for a generic application, normally a one-time test establishing typical performance of the product. Tests not specifically identified as being performed only for qualification purposes should be interpreted as "batch tests." Batch tests are tests to be made on each production batch of product to establish suitability for a specific application.


If impregnated activated carbon is used as the adsorbent, the adsorber system should be designed for an average atmosphere residence time of 0.25 seconds per two inches of adsorbent bed. Sections FD and FE of ASME AG-1-1997 should be used to determine the residence time.
System design should consider potential airborne contaminants from offsite sources, such as nearby industrial facility discharges of dusts, combustion particulates and gases, dust storms, or salt spray particulate from nearby oceans or bays.


If an adsorbent other than impregnated activated carbon is proposed or if the mesh size distribution or other physical properties of the impregnated activated carbon are different from the specifications above, the proposed adsorbent should have the capability to perform as well as or better than activated carbon that satisfies the specifications in Article FF of ASME AG-1-1997.
f.


If sample canisters are used, they should be designed in accordance with Appendix A to ASME N509-1989 (Ref. 1).
Normal atmosphere cleanup system housings and ductwork should be designed to limit system total leakage rate, as defined in Article SA-4500 of ASME AG-1b-2009. Duct and housing leak tests should be performed consistent with Section TA of ASME AG-1b-
          4.10. Ductwork associated with the normal atmosphere cleanup system should be de- signed, constructed, and tested in accordance with Section SA of ASME AG-1-1997.
2009.


4.11. Ducts and housings should be laid out with a minimum of ledges, protrusions, and crevices that could collect dust and moisture and that could impede personnel or create a hazard to them in the performance of their work. Turning vanes or other air flow distribution devices should be installed where required to ensure representative air flow measurement and uniform flow distri- bution through cleanup components.
g.


4.12. Dampers should be designed, constructed, and tested in accordance with Section DA of ASME AG-1-1997.
For power cycle waste offgas systems relying on activated carbon delay tanks or beds, the above system design criteria are deemed applicable, but should be evaluated and applied taking into consideration the systems specific design features.


4.13. The system fan and motor, mounting, and ductwork connections should be designed, constructed, and tested in accordance with ASME AG-1-1997 in Section BA for Blowers and Section SA for Ducts. The fan and motor used in the normal atmosphere cleanup system should be capable of operating under the environmental conditions postulated for its use.
4.


2 A batch of activated carbon or a batch of impregnated activated carbon is a quantity of adsorbent, not to exceed 10 cubic meters (or 350 cubic feet), of the same grade or type that has been produced under the same manufacturers production designation using a consistent manufacturing procedure and equipment, and that has been homogenized to exhibit the same physical properties and performance characteristics throughout the mass. (See Article FF-1130 of ASME AG-1-1997).
Component Design Criteria and Qualification Testing
3 A "lot of activated carbon" or a "lot of impregnated activated carbon" is a quantity of adsorbent consisting of one or more batches of adsorbent that constitute and satisfy a purchase order. (See Article FF-1130 of ASME AG-1-1997).
                                                              1.140-8


5.        MAINTAINABILITY CRITERIA
Components of normal atmosphere cleanup systems should be designed, constructed, and tested in accordance with Division II of ASME AG-1b-2009, as modified and supplemented by the following:
          Provisions for maintaining normal atmosphere cleanup systems should be incorporated in the system design in accordance with Section 4.8 of ASME N509-1989 (Ref. 1) and Section HA of ASME AG-1a-2000 (Ref. 7) as supplemented by the following.
a.


5.1.      Accessibility of components and maintenance should be considered in the design of normal atmosphere cleanup systems in accordance with Section 2.3.8 of ERDA 76-21 (Ref. 5) and Section HA of ASME AG-1a-2000 (Ref. 7). For ease of inspection and maintenance, the system design should provide for a minimum of 3 feet from mounting frame to mounting frame between banks of components. If components are to be replaced, the dimensions to be provided should be the maximum length of the component plus a minimum of 3 feet.
Prefilters should be designed, constructed, and tested consistent with Sections FB or FJ of ASME AG-1b-2009.


5.2.      The cleanup components (i.e., HEPA filters, prefilters, and adsorbers) that are used during construction of the ventilation systems should be replaced before the system is declared operable.
b.


6.        IN-PLACE TESTING CRITERIA
Air heaters should be designed, constructed, and tested consistent with Section CA of ASME AG-1b-2009.
          Initial in-place testing of normal atmosphere cleanup systems should be performed in accordance with Section TA of ASME AG-1-1997 (Ref. 3). Periodic, in-place testing of normal atmosphere cleanup systems and components should be performed in accordance with ASME
N510-1989 (Ref. 2) as modified and supplemented by the following:
          6.1.      A visual inspection of the normal atmosphere cleanup system and all associated components should be performed in accordance with Section 5 of ASME N510-1989.


6.2.       In-place aerosol leak tests for HEPA filters upstream from the carbon adsorbers in normal atmosphere cleanup systems should be performed (1) initially, (2) at least once each 24 months, (3) after each partial or complete replacement of a HEPA filter bank, (4) following detection of, or evidence of, penetration or intrusion of water or other material into any portion of a normal atmosphere cleanup system that may have an adverse effect on the functional capability of the filters,4 and (5) following painting, fire, or chemical release in any ventilation zone communicating with the system that may have an adverse effect on the functional capability of the system.5 The test should be performed in accordance with Section 10 of ASME N510-1989 (Ref.
RG 1.140, Rev. 3, Page 9


4 In 1998, the Department of Energy (DOE) presented the results of its HEPA filter deterioration research at the 25th DOE/NRC
c.
Nuclear Air Cleaning and Treatment Conference (Ref. 8). The results of this research demonstrated that wetting of the filter medium significantly reduces its tensile strength, which is not fully recovered after drying. In addition, further water exposures resulted in additional losses in filter media tensile strength. (See NRC Information Notice 99-01, Ref. 9).
5 Painting, fire, or chemical release is not communicating with the HEPA filter or adsorber if the ESF atmosphere cleanup system is not in operation, the isolation dampers for the system are closed, and there is no pressure differential across the filter housing. This provides reasonable assurance that air is not passing through the filters and adsorbers. A program should be developed and consistently applied that defines the terms painting, fire, and chemical release in terms of the potential for degrading the HEPA filters and adsorbers. This program should be based on a well-documented, sound and conservative technical basis (i.e., the criteria should overestimate the potential damage to the filter and adsorber).
                                                                1.140-9


2). The leak test should confirm a combined penetration and leakage (or bypass)6 of the normal atmosphere cleanup system of less than 0.05% of the challenge aerosol at rated flow +/-10%. A
HEPA filters should be designed, constructed, and tested consistent with Sections FC of ASME AG-1b-2009. HEPA filters should be compatible with the chemical and physical composition and physical conditions of the air stream. Each HEPA filter should be tested for penetration of a challenge aerosol, such as dioctyl phthalate or 4-centistoke poly- alpha olephin, in accordance with Section TA of ASME AG-1b-2009.
filtration system satisfying this condition can be considered to warrant a 99% removal efficiency for particulates.


HEPA filter sections in normal atmosphere cleanup systems that fail to satisfy the appropriate leak-test conditions should be examined to determine the location and cause of leaks.
d.


Repairs, such as alignment of filter frames and tightening of filter hold-down bolts, may be made;
HEPA and Type II adsorber cell mounting frames should be designed and constructed in accordance with Section FG of ASME AG-1b-2009.
however, repair of defective, damaged, or torn filter media by patching or using caulking materials is not recommended in normal atmosphere cleanup systems, and such filters should be replaced and not repaired. HEPA filters that fail to satisfy test conditions should be replaced with filters qualified pursuant to Regulatory Position 4.3 of this guide. After repairs or filter replacement, the normal atmosphere cleanup system should be retested as described above in this Regulatory Position.


In accordance with ASME N510-1989 (Ref. 2) and Article TA-1000 of ASME AG-1-1997 (Ref. 3), the standard challenge aerosol used in the in-place leak testing of HEPA filters is polydisperse droplets of dioctyl phthalate (DOP), also known as di-2-ethylhexyl-phthalate (DEHP).
e.
The 0.3 micrometer monodisperse DOP aerosol is used for efficiency testing of individual HEPA
filters by manufacturers. Alternative challenge agents7 may be used to perform in-place leak testing of HEPA filters when their selection is based on the following.


1. The challenge aerosol has the approximate light scattering droplet size specified in Article TA-1130 of ASME AG-1-1997
Filter and adsorber sections should be arranged in accordance with Section HA of ASME AG-1b-2009.
            2. The challenge aerosol has the same in-place leak test results as DOP.


3. The challenge aerosol has similar lower detection limit, sensitivity, and precision as DOP.
f.


4. The challenge aerosol causes no degradation of the HEPA filter or the other normal air cleaning system components under test conditions.
Filter housings, including floors and doors, and electrical conduits, drains, and other piping installed inside filter housings should be designed and constructed in accordance with Section HA of ASME AG-1b-2009.


5. The challenge aerosol is listed in the Environmental Protection Agency's Toxic Substance Control Act (TSCA) (Ref. 11) inventory for commercial use.
g.


6.3.      In-place leak testing for adsorbers should be performed (1) initially, (2) at least once each 24 months, (3) following removal of an adsorber sample for laboratory testing if the integrity of the adsorber section is affected, (4) after each partial or complete replacement of carbon adsorber in an adsorber section, (5) following detection of, or evidence of, penetration or intrusion of water or other material into any portion of a normal atmosphere cleanup system that may have an adverse effect on the functional capability of the adsorbers, and (6) following painting, fire, or
If the relative humidity of the atmosphere entering the air cleanup system can be expected to exceed 70 percent during normal operation, the design should include heaters or cooling coils, or both, to maintain relative humidity at or below 70 percent to ensure adsorption unit efficiency. Heaters should be designed, constructed, and tested in accordance with Section CA of ASME AG-1b-2009.
6 In Section FD-1130 of ASME AG-1-1997 (Ref. 3), penetration is defined as the exit concentration of a given gas from an air cleaning device, expressed as a percentage of inlet concentration. In Section 3 of ASME N509-1989 (Ref. 1), bypass is defined as a pathway through which contaminated air can escape treatment by the installed HEPA or adsorber banks. Examples are leaks in filters and filter mounting frames, defective or inefficient isolation dampers that result in uncontrolled flow through adjacent plenums, and unsealed penetrations for electrical conduits, pipes, floor drains, etc.


7 Care should be taken to ensure that the aerosol generator is compatible with the selected alternative challenge agent (see NRC
h.
Information Notice 99-34, Ref. 10).
                                                                1.140-10


chemical release in any ventilation zone communicating with the system that may have an adverse effect on the functional capability of the system.5 The test should be performed in accordance with Section 11 of ASME N510-1989 (Ref. 2). The leak test should confirm a combined penetration and leakage (or bypass)6 of the adsorber section of 0.05% or less of the challenge gas at rated flow+/-10%.
Adsorber cells should be designed, constructed, and tested in accordance with Section FD
        Adsorber sections that fail to satisfy the appropriate leak-test conditions should be examined to determine the location and cause of leaks. Repairs, such as alignment of adsorber cells, tightening of adsorber cell hold-down bolts, or tightening of test canister fixtures, may be made; however, the use of temporary patching material on adsorbers, filters, housings, mounting frames, or ducts should not be allowed. After repairs or adjustments have been made, the adsorber sections should be retested as described above in this Regulatory Position.
for Type II or Section FE for Type III or Section FH of ASME AG-1b-2009 for Type IV
adsorber cells.


In accordance with ASME N510-1989 (Ref. 2) and Section TA of ASME AG-1-1997 (Ref.
(1)  
Design of an adsorber section should consider possible iodine desorption and adsorbent autoignition that may result from radioactivity-induced heat in the adsorbent and concomitant temperature rise. If needed, prevention and mitigation features could include low-flow air or inert gas bleed, cooling coils, cleanup unit isolation, or water sprays.


3), the standard challenge gas used in the in-place leak testing of adsorbers is Refrigerant-11 (trichloromonofluoromethane). Alternative challenge gases may be used to perform in-place leak testing of adsorbers when their selection is based on meeting the characteristics specified in Appendix TA-C of ASME AG-1-1997.
(2)  
If a water-based fire suppression or prevention (cooling) system is installed in a normal atmosphere cleanup system housing, it should be designed for manual actuation unless a reasonable possibility exists that iodine desorption and adsorbent autoignition could occur in the housing. If autoignition is a reasonable possibility, the fire suppression system should have both manual and automatic actuation. The fire suppression system should use open spray nozzles of sufficient size, number, and location to provide complete coverage over the entire surface of the combustible filter/adsorber media. The fire system should be hard piped and supplied with a reliable source of water of adequate pressure and flow.


6.4. If any welding repairs are necessary on, within, or adjacent to the ducts, housing, or mounting frames, the HEPA filters and adsorbers should be removed from the housing (or otherwise protected) prior to performing such repairs. The repairs should be completed prior to re- installation of filters and adsorbers; the system should then be visually inspected and leak tested as in Regulatory Positions 6.2, 6.3, and 6.4.
Location of the water supply manual actuation device should be remote from the cleanup system housing and consistent with the guidance of RG 8.8. Reliable mechanical or electrical detection devices sensing temperature, smoke, carbon monoxide, or other indications of fire ignition should be included in the system for manual and automatic actuation methods. Monitoring indicators for these detector outputs should be remote from the system housings and consistent with the guidance of RG 8.8 and support the manual actuation capability. Cross- zoning of detectors may be used for automatic actuation.


7.      LABORATORY TESTING CRITERIA FOR ACTIVATED CARBON
RG 1.140, Rev. 3, Page 10
        7.1. The activated carbon adsorber section of the normal atmosphere cleanup system should be assigned the decontamination efficiencies given in Table 1 for radioiodine if the following conditions are met:
        1.      The adsorber section meets the conditions given in Regulatory Position 6.3 of this guide,
        2.      New activated carbon meets the physical property specifications given in Regulatory Position 4.9 of this guide, and
        3.      Representative samples of used activated carbon pass the laboratory tests given in Table 1 of this guide.


If the activated carbon fails to meet any of the above conditions, it should not be used in adsorption units.
(3)
For portions of atmospheric clean up systems and power cycle off gas systems (such as filter housings, delay tanks or beds, and low-points in ductwork), the design should consider features to collect and drain accumulated water from various sources. The presence and accumulation of water within portions of these systems may be attributed to condensation and from water-based fire suppression systems, when triggered. The design should provide the means to collect and route water to the appropriate radioactive waste management system given that the water would entrain radioactive materials present in such systems.


7.2. The efficiency of the activated carbon adsorber section should be determined by laboratory testing of representative samples of the activated carbon exposed simultaneously to the same service conditions as the adsorber section. Each representative sample should be not less
(4)
                                                1.140-11
The design of water collection systems and drains should consider the requirements of 10 CFR 20.1406 in minimizing the contamination of plant facilities and the environment. Additional guidance supporting 10 CFR 20.1406 is presented in: 


than 2 inches in both length and diameter, and each sample should have the same qualification and batch test characteristics as the system adsorbent. There should be a sufficient number of representative samples located in parallel with the adsorber section to estimate the amount of penetration of the system adsorbent throughout its service life. The design of the samples should be in accordance with Appendix A to ASME N509-1989 (Ref. 1). Where system activated carbon is greater than 2 inches deep, each representative sampling station should consist of enough 2-inch samples in series to equal the thickness of the system adsorbent. Once representative samples are removed for laboratory testing, their positions in the sampling array should be blocked off.
1. Regulatory Guide 1.143, which describes systems handling of radioactive materials in liquids, gaseous and solid collection systems that include construction of structures. Further, RG 4.21 gives guidance for design of facilities to minimize contamination of the facility and the environment, and the generation of waste.


Sampling and analysis should be performed (1) initially, (2) at intervals of approximately
2. NUREG-0800 gives NRC review criteria for nuclear power plants.
24 months, (3) following painting, fire, or chemical release in any ventilation zone communicating with the system that may have an adverse effect on the functional capability of the carbon media,5 and (4) following detection of, or evidence of, penetration of water or other material into any portion of the filter system that may have an adverse effect on the functional capability of the carbon media.


Laboratory tests of representative samples should be conducted, as indicated in Table 1 of this guide, with the test gas flow in the same direction as the flow during service conditions.
3. Nuclear Energy Institute (NEI) technical report NEI 08-08A Guidance for Life Cycle Minimization of Contamination (Ref. 16), provides a method for licensees to describe operational policies and operational programs to meet the programmatic requirements of 10 CFR Part 20.1406(a) and (b) for life cycle minimization of contamination. Meeting these requirements is achieved, in part, by addressing the applicable regulatory position elements of RG 4.21.


Similar laboratory tests should be performed on an adsorbent sample before loading into the adsorbers to establish an initial point for comparison of future test results. The activated carbon adsorber section should be replaced with new unused activated carbon meeting the physical property specifications given in Regulatory Position 4.9 of this guide if (1) testing in accordance with Table 1 results in a representative sample that fails to pass the acceptance criterion or (2) no representative sample is available for testing.
The main objective of the regulations and NRC guidance is to avoid unmonitored and uncontrolled releases of radioactive materials on the site and in uncontrolled areas, and provide information that can be used to assess potential radiological hazards.
 
i.
 
The adsorber section of the normal atmosphere cleanup system may contain any adsorbent material demonstrated to remove gaseous iodine (elemental iodine and organic iodides) from air with the required efficiency or better.
 
(1)
Each original or replacement batch or lot of impregnated activated carbon media used in an adsorber section should be prepared, inspected, and tested consistent with Section FF of ASME AG-1b-2009.
 
(2)
If impregnated activated carbon media is used, the adsorber section design should provide for a minimum atmosphere residence time of 0.05 seconds per centimeter
(0.125 seconds per inch) of adsorbent media bed depth at rated flow.
 
(3)
Sections FD, FE, and FH of ASME AG-1b-2009 should be used to determine residence time.
 
RG 1.140, Rev. 3, Page 11
 
(4)
If sample (inservice test) canisters are used, their design should be consistent with Section FE of ASME AG-1b-2009 or Appendix I to ASME N509-2002.
 
j.
 
Ductwork should be designed, constructed, and tested consistent with Section SA of ASME AG-1b-2009.
 
k.
 
Duct and housing layout designs should minimize ledges, protrusions, and crevices that could collect dust and moisture and impede personnel work performance or create avoidable industrial safety hazards. Turning vanes or other airflow distribution devices should be installed where needed to achieve acceptably uniform flow profiles and support representative airflow measurements.
 
l.
 
Dampers should be designed, constructed, and tested consistent with Section DA of ASME AG-1b-2009.
 
m.
 
Fan/blower and motor, mounting, and ductwork connections should be designed, constructed, and tested consistent with Section BA for fans/blowers and Section SA of ASME AG-1b-2009 for ducts.
 
n.
 
For power cycle waste offgas systems relying on activated carbon delay tanks or beds, the above component design criteria and qualification testing are deemed applicable, but should be evaluated and applied taking into consideration the systems specific design features.
 
5.
 
Maintainability Criteria
 
Cleanup system design should incorporate provisions for maintenance consistent with Section HA of ASME AG-1b-2009 as modified and supplemented by the following:
a.
 
System design should support accessibility for inspection and maintenance. Filtration unit enclosures should provide a minimum of 0.92 meters (3 feet) from mounting frame to mounting frame between banks of components. Where components within a bank are designed for replacement, the spacing between banks should be the length of the component plus at least 0.92 meters (3 feet).
b.
 
Cleanup system components (i.e., HEPA filters, prefilters, and adsorbers) that are used during system construction should be replaced before the system is declared fully functional.
 
c.
 
Duct access for inspection and maintenance should be provided consistent with the guidance of Section 4.3.4 of National Fire Protection Association (NFPA) 90A,
Standard for the Installation of Air Conditioning and Ventilation Systems (Ref. 17).
d.
 
For power cycle waste offgas systems relying on activated carbon delay tanks or beds, the above maintainability criteria are deemed applicable, but should be evaluated and applied taking into consideration the systems specific design features.
 
RG 1.140, Rev. 3, Page 12
 
6.
 
In-Place Testing Criteria
 
Initial in-place testing of normal atmosphere cleanup systems should be performed consistent with Section TA of ASME AG-1b-2009. Periodic in-place testing of the cleanup systems and components should be performed consistent with ASME N511-2007 as modified and supplemented by the following:
a.
 
A visual inspection of the normal atmosphere cleanup system and all associated components should be performed consistent with Appendix I to ASME N511-2007.
 
b.
 
In-place aerosol leak tests for HEPA filters upstream from the carbon adsorbers should be performed (1) consistent with and at the frequency intervals shown in Section 5.7 and Appendix III to ASME N511-2007 , (2) after each partial or complete replacement of a HEPA filter bank, (3) following detection of, or evidence of, penetration or intrusion of water or other material into any portion of a cleanup system that may have an adverse effect on the functional capability of the filters, and (4) following painting, fire, or chemical release in any ventilation zone communicating with the system that may have an adverse effect on the functional capability of the system. The leak test should confirm a combined penetration and leakage (or bypass) of the normal atmosphere cleanup system of less than 0.05 percent of the challenge aerosol at a system-rated flow +/-10 percent to warrant a 99-percent removal efficiency for particulates.
 
c.
 
HEPA filter sections that fail to satisfy appropriate leak test criteria should be examined to determine location and cause of leaks. Adjustments, such as alignment of filter cases and tightening of filter hold-down fasteners, may be made. Defective, damaged, or torn filter media should not be repaired by patching and caulking; filters should be replaced and not repaired. After adjustments or filter replacement, the cleanup system should be retested.
 
d.
 
Cleanup system adsorbers should be in-place leak tested (1) consistent with and at the frequency intervals shown in Section 5.8 and Appendix IV to ASME N511-2007,
(2) following removal of an adsorber sample for laboratory testing if the integrity of the adsorber section is affected, (3) after each partial or complete replacement of carbon adsorber in an adsorber section, (4) following detection of, or evidence of, penetration or intrusion of water or other material into any portion of a normal atmosphere cleanup system that may have an adverse effect on the functional capability of the adsorbers, and
(5) following painting, fire, or chemical release in any ventilation zone communicating with the system that may have an adverse effect on the functional capability of the system. The leak test should confirm a combined penetration and leakage (or bypass) of the adsorber section of 0.05 percent or less of the challenge gas at a system-rated flow
+/-10 percent.
 
e.
 
Adsorber sections that fail to satisfy the appropriate leak test conditions should be examined to determine the location and cause of leaks. Adjustments, such as alignment of adsorber cells, tightening of adsorber cell hold-down fasteners, or tightening of test canister fixtures, may be made. Defective or damaged adsorber cells, mounting frames, or housings should not be temporarily repaired with patching material or caulking. After adjustments or adsorber cell replacement, the cleanup system should be retested.
 
f.
 
Painting, fire, or chemical release is not communicating with the HEPA filter or adsorber if the cleanup system is not in operation, the isolation dampers are closed, and there is no pressure differential across the filter housing. This provides reasonable
 
RG 1.140, Rev. 3, Page 13
 
assurance that air is not passing through the filters and adsorbers. Conservative, well- documented administrative controls should be implemented that define the terms painting, fire, and chemical release with respect to the potential for degrading cleanup system HEPA filters and adsorbers.
 
g.
 
If welding repairs are performed on, within, or adjacent to the cleanup system ducts, housing, or mounting frames, the HEPA filters and adsorbers should first be removed from the housing (or otherwise protected). When repairs are completed and filters and adsorbers reinstalled, the cleanup system should be visually inspected and leak tested as described in Regulatory Positions 6.a, 6.b, and 6.d of this guide.
 
h.
 
For power cycle waste offgas systems relying on activated carbon delay tanks or beds, the above in place testing criteria are deemed applicable, but should be evaluated and applied taking into consideration the systems specific design features.
 
7.
 
Laboratory Testing Criteria for Activated Carbon a.
 
Activated carbon adsorber sections of the cleanup system should be assigned the decontamination efficiencies given in Table 1 for radioiodine if the following conditions are met:
(1)
The adsorber section meets the conditions given in Regulatory Position 6.d of this guide.
 
(2)
New activated carbon meets the physical property specifications given in Regulatory Position 4.i of this guide.
 
(3)
Representative samples of used activated carbon pass the laboratory tests given in Table 1 of this guide.
 
b.
 
Efficiency of an activated carbon adsorber section should be determined by laboratory testing of representative samples of the activated carbon experiencing the same service conditions and the same exposure to all contaminants as the entire adsorber section. Each representative sample should be 5.1 centimeters (2 inches) or more in both length and diameter, and each sample should have the same qualification and batch test characteristics as the system adsorbent. A sufficient number of representative samples should be located in parallel with the adsorber section to allow periodic determination of system adsorbent penetration throughout its service life. Where system activated carbon adsorber is greater than 5.1 centimeters (2 inches) deep, each representative sampling should consist of an equivalent depth. Once representative samples are removed for laboratory testing, the positions they occupied should be blocked off to maintain adsorber section capability.
 
c.
 
Sampling and analysis of adsorbent should be performed (1) consistent with and at the frequency intervals shown in Sections 7 and 5.9 of ASME N511-2007, (2) following painting, fire, or chemical release in any ventilation zone communicating with the system that may have an adverse effect on the functional capability of the carbon media, and (3)
following detection of, or evidence of, penetration or intrusion of water or other material into any portion of a normal atmosphere cleanup system that may have an adverse effect on the functional capability of the adsorber media.
 
RG 1.140, Rev. 3, Page 14
 
d.
 
Laboratory tests of representative samples of adsorbent should be conducted as indicated in Table 1 of this guide, with the test gas flow in the same direction as normal cleanup system flow unless using bulk sample extraction methods from deep bed adsorbers.
 
Similar laboratory tests should be performed on a sample before loading media into the adsorber section to establish a baseline for comparison with future sample test results.
 
The contents of an activated carbon adsorber section should be replaced with new, unused activated carbon adsorbent meeting the physical properties identified in Regulatory Position 4.i of this guide if (1) testing in accordance with Table 1 of this guide results in a representative sample failing an acceptance criterion or (2) no representative sample is available for testing.
 
e.
 
For power cycle waste offgas systems relying on activated carbon delay tanks or beds, the above laboratory testing criteria for activated carbon are deemed applicable, but should be evaluated and applied taking into consideration the systems specific design features.
 
Table 1. Inservice Adsorber Laboratory Tests for Activated Carbon
 
Activated Carbon Total Bed Depth
 
Maximum Assigned Activated Carbon Decontamination Efficiencies Methyl Iodide Penetration Acceptance Criterion for Representative Sample
 
2 inches
 
Elemental iodine
 
Organic iodide
95%
 
95%
Penetration 5% when tested in accordance with ASTM D3803-1991
 
4 inches or greater (in-series beds are treated as a single bed of aggregate depth)
 
Elemental iodine
 
Organic iodide
99%
 
99%
Penetration 1% when tested in accordance with ASTM D3803-1991 Activated carbon in delay tanks or beds Elemental iodine
 
Organic iodide
99%
 
99%
Penetration 1% when tested in accordance with ASTM D3803-1991 
 
Table 1 Notes:
(1)
See Appendix I to ASME N509-2002 for the definition of a representative sample.
 
(2)
Credited decontamination efficiencies (a portion of which includes bypass leakage) are based on a
0.25-second residence time per 5.1 centimeter (2-inch bed depth).
(3)
The activated carbon, when new, should meet the specifications of Regulatory Position 4.i of this guide. Table 1 provides acceptable decontamination efficiencies and methyl iodide test penetrations of used activated carbon samples for laboratory testing. Testing should be performed at the frequencies specified in Regulatory Position 7.c of this guide. Testing should be performed in accordance with American Society for Testing and Materials (ASTM) D3803-1991 (Reaffirmed 2014, Standard Test Methods for Nuclear-Grade Activated Carbon (Ref. 18), with an entering air temperature of 30 degrees Celsius (86 degrees Fahrenheit) and a relative humidity of 95 percent (or 70 percent with humidity control). Humidity control can be provided by heaters, cooling coils, or an analysis that demonstrates that the air entering the installed adsorber section would be maintained less than or equal to a 70-percent relative humidity level.
 
RG 1.140, Rev. 3, Page 15
 
(4)
Organic iodide and elemental iodine are the forms of iodine that are expected to be absorbed by activated carbon. Organic iodide is more difficult for activated carbon to adsorb than elemental iodine. Therefore, the laboratory test to determine the performance of the activated carbon adsorber is based on organic iodide. Methyl iodide is the organic form of iodine that is used in the laboratory test.
 
(5)
For power cycle waste offgas systems relying on activated carbon delay tanks or beds, the inservice adsorber laboratory tests should confirm that the proper types of activated carbon (nuclear grade and defined mesh size) are tested for representative batches of activated carbon over the entire design inventory of the waste offgas treatment system, given the design capacity and number of delay tanks or beds.
 
RG 1.140, Rev. 3, Page 16


==D. IMPLEMENTATION==
==D. IMPLEMENTATION==
The purpose of this section is to provide information to applicants and licensees regarding the NRC staff's plans for using this regulatory guide.
The purpose of this section is to provide information on how applicants and licensees1 may use this guide and information regarding the NRCs plans for using this regulatory guide. In addition, it describes how the NRC staff complies with 10 CFR 50.109, Backfitting and any applicable finality provisions in 10 CFR Part 52, Licenses, Certifications, and Approvals for Nuclear Power Plants.
 
Use by Applicants and Licensees Applicants and licensees may voluntarily2 use the guidance in this document to demonstrate compliance with the underlying NRC regulations. Methods or solutions that differ from those described in this regulatory guide may be deemed acceptable if they provide sufficient basis and information for the NRC staff to verify that the proposed alternative demonstrates compliance with the appropriate NRC
regulations. Current licensees may continue to use guidance the NRC found acceptable for complying with the identified regulations as long as their current licensing basis remains unchanged.
 
Licensees may use the information in this regulatory guide for actions which do not require NRC
review and approval such as changes to a facility design under 10 CFR 50.59, Changes, Tests, and Experiments. Licensees may use the information in this regulatory guide or applicable parts to resolve regulatory or inspection issues.
 
Use by NRC Staff The NRC staff does not intend or approve any imposition or backfitting of the guidance in this regulatory guide. The NRC staff does not expect any existing licensee to use or commit to using the guidance in this regulatory guide, unless the licensee makes a change to its licensing basis. The NRC staff does not expect or plan to request licensees to voluntarily adopt this regulatory guide to resolve a generic regulatory issue. The NRC staff does not expect or plan to initiate NRC regulatory action which would require the use of this regulatory guide. Examples of such unplanned NRC regulatory actions include issuance of an order requiring the use of the regulatory guide, requests for information under
10 CFR 50.54(f) as to whether a licensee intends to commit to use of this regulatory guide, generic communication, or promulgation of a rule requiring the use of this regulatory guide without further backfit consideration.
 
During regulatory discussions on plant specific operational issues, the staff may discuss with licensees various actions consistent with staff positions in this regulatory guide, as one acceptable means of meeting the underlying NRC regulatory requirement. Such discussions would not ordinarily be considered backfitting even if prior versions of this regulatory guide are part of the licensing basis of the facility. However, unless this regulatory guide is part of the licensing basis for a facility, the staff may not represent to the licensee that the licensees failure to comply with the positions in this regulatory guide constitutes a violation.
 
If an existing licensee voluntarily seeks a license amendment or change and (1) the NRC staffs consideration of the request involves a regulatory issue directly relevant to this new or revised regulatory guide and (2) the specific subject matter of this regulatory guide is an essential consideration in the staffs
 
1 In this section, licensees refers to licensees of nuclear power plants under 10 CFR Parts 50 and 52; and the term applicants, refers to applicants for licenses and permits for (or relating to) nuclear power plants under 10 CFR Parts
50 and 52, and applicants for standard design approvals and standard design certifications under 10 CFR Part 52.
 
2 In this section, voluntary and voluntarily means that the licensee is seeking the action of its own accord, without the force of a legally binding requirement or an NRC representation of further licensing or enforcement action.
 
RG 1.140, Rev. 3, Page 17
 
determination of the acceptability of the licensees request, then the staff may request that the licensee either follow the guidance in this regulatory guide or provide an equivalent alternative process that demonstrates compliance with the underlying NRC regulatory requirements. This is not considered backfitting as defined in 10 CFR 50.109(a)(1) or a violation of any of the issue finality provisions in 10
CFR Part 52.
 
Additionally, an existing applicant may be required to comply to new rules, orders, or guidance if
10 CFR 50.109(a)(3) applies.
 
If a licensee believes that the NRC is either using this regulatory guide or requesting or requiring the licensee to implement the methods or processes in this regulatory guide in a manner inconsistent with the discussion in this Implementation section, then the licensee may file a backfit appeal with the NRC in accordance with the guidance in NRC Management Directive 8.4, Management of Facility-Specific Backfitting and Information Collection (Ref. 19) and NUREG-1409, Backfitting Guidelines, (Ref. 20). 
 
RG 1.140, Rev. 3, Page 18
 
REFERENCES3
1.
 
U.S. Code of Federal Regulations (CFR) Domestic Licensing of Production and Utilization Facilities, Part 50, Chapter 1, Title 10, Energy, Washington, DC.
 
2.
 
CFR, Licenses, Certifications, and Approvals for Nuclear Power Plants, Part 52, Chapter 1, Title 10, Energy, Washington, DC.
 
3.
 
CFR, 10 CFR 20.1406, Minimization of contamination, U.S. Nuclear Regulatory Commission, Washington DC.
 
4.
 
Nuclear Regulatory Commission (NRC), Regulatory Guide 1.52, Design, Inspection, and Testing Criteria for Air Filtration and Adsorption Units of Post-Accident Engineered-Safety- Feature Atmosphere Cleanup Systems in Light-Water-Cooled Nuclear Power Plants, Washington, DC.
 
5.
 
NRC, Regulatory Guide 1.143, Design Guidance for Radioactive Waste Management Systems, Structures and Components Installed in Light-Water-Cooled Nuclear Reactor Power Plants, Washington, DC.
 
6.
 
NRC, Regulatory Guide 4.21, Minimization of Contamination and Radioactive Waste Generation: Life Cycle Planning, Washington, DC.
 
7.
 
NRC, NUREG-0800 Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants: LWR Edition 
8.
 
American Society of Mechanical Engineers (ASME) AG-1b-2009, Code on Nuclear Air and Gas Treatment, 2009, including 2010 Addenda 1a and 2011 Addenda 1b, American Society of Mechanical Engineers, New York, NY.4
9.
 
ASME N509-2002 (Reaffirmed 2008), Nuclear Power Plant Air-Cleaning Units and Components, American Society of Mechanical Engineers, New York, NY.
 
10.
 
ASME N510-2007, Testing of Nuclear Air-Treatment Systems, American Society of Mechanical Engineers, New York, NY.
 
11.
 
ASME N511-2007, Standard N511, Inservice Testing of Nuclear Air Treatment, Heating, Ventilating, and Air-Conditioning Systems, American Society of Mechanical Engineers, New York, NY.


Except in those cases in which an applicant or licensee proposes an acceptable alternative method for complying with specified portions of the NRC's regulations, the methods described in this guide, which reflect public comments, will be used by the NRC staff in its evaluation of submittals in connection with the design, inspection, and testing of normal atmosphere cleanup systems for the following light-water-cooled nuclear power plants:
3 Publicly available documents from the U.S. Nuclear Regulatory Commission (NRC) are available electronically through the NRC Library on the NRCs public Web site at http://www.nrc.gov/reading-rm/doc-collections/. The documents can also be viewed on-line for free or printed for a fee in the NRCs Public Document Room (PDR) at
        1.     Plants for which the construction permit or license application is docketed after the issue date of this guide;
11555 Rockville Pike, Rockville, MD; the mailing address is USNRC PDR, Washington, DC 20555; telephone (301)
        2.     Plants for which the licensee voluntarily commits to the provisions of this guide.
415-4737 or (800) 397-4209; fax (301) 415 3548; and e-mail pdr.resource@nrc.gov.


1.140-12
4 Copies of American Society of Mechanical Engineers (ASME) standards may be purchased from ASME, Two Park Avenue, New York, New York 10016-5990; telephone (800) 843-2763. Purchase information is available through the ASME Web-based store at http://www.asme.org/Codes/Publications/.


Table 1: Laboratory Tests For Activated Carbon Activated Carbona                  Maximum Assigned Activated                            Methyl Iodide Penetration Total Bed Depthb                      Carbon Decontamination                              Acceptance Criterion for Efficiencies                              Representative Sample
RG 1.140, Rev. 3, Page 19
  2 inches                        Elemental iodine                        95%          Penetration 5% when tested in accordance with ASTM D-3803- Organic iodide                          95%          1989 (Ref. 4)
  4 inches or greater            Elemental iodine                        99%          Penetration 1% when tested in accordance with ASTM D-3803- Organic iodide                          99%          1989 (Ref. 4)
a The activated carbon, when new, should meet the specifications of Regulatory Position 4.9 of this guide.


b Multiple beds, e.g., two 2-inch beds in series, should be treated as a single bed of aggregate depth. It is advantageous when series beds are located in separate housings and individually in-place leak tested. This aids in mixing the challenge agent and contributes to the accuracy of the test results.
12.


NOTES:
International Atomic Energy Agency (IAEA), NS-G-1.10, Design of Reactor Containment Systems of Nuclear Power Plants, Vienna, Austria. 5
(1) Credited decontamination efficiencies (a portion of which includes bypass leakage) are based on 0.25 second residence time per 2-inch bed depth.
13.


(2) Organic iodide and elemental iodine are the forms of iodine that are expected to be absorbed by activated carbon.
IAEA, NS-G-2.7, Radiation Protection and Radioactive Waste Management in the Operation of Nuclear Power Plants, Vienna, Austria.


Organic iodide is more difficult for activated carbon to adsorb than elemental iodine. Therefore, the laboratory test to determine the performance of the activated carbon adsorber is based on organic iodide. Methyl iodide is the organic form of iodine that is used in the laboratory test.
14.


(3) This Table 1 provides acceptable decontamination efficiencies and methyl iodide test penetrations of used activated carbon samples for laboratory testing. Laboratory tests are conducted in accordance with ASTM D3803-
IAEA, SSR-2/1, Safety of Nuclear Power Plants:  Design, Vienna, Austria.
1989 (Ref. 4). Tests are conducted at a temperature of 30&deg;C and relative humidity of 95%, except a relative humidity of 70% is used when the air entering the carbon adsorber is maintained at less than or equal to 70% relative humidity.


(4) See Appendix A to ASME N509-1989 (Ref. 1) for the definition of a representative sample. Testing should be performed at the frequencies specified in Regulatory Position 7.2 of this guide. Testing should be performed in accordance with ASTM D3803-1989 (Ref. 4) at a temperature of 30&deg;C and a relative humidity of 95% (or 70% with humidity control). Humidity control can be provided by heaters or an analysis that demonstrates that the air entering the carbon will be maintained less than or equal to 70% relative humidity.
15.


1.140-13
NRC, Regulatory Guide 8.8, Information Relevant to Ensuring that Occupational Radiation Exposures at Nuclear Power Stations Will Be As Low As Is Reasonably Achievable, Washington, DC.


REFERENCES
16.
1.        American Society of Mechanical Engineers, "Nuclear Power Plant Air-Cleaning Units and Components," ASME N509-1989. Reaffirmed 1996.


2.        American Society of Mechanical Engineers, "Testing of Nuclear Air-Treatment Systems,"
Nuclear Energy Institute (NEI) technical report NEI 08-08A Guidance for Life Cycle Minimization of Contamination, (ADAMS Accession Number ML093220530,  
          ASME N510-1989. Reaffirmed 1995.
ML092720253)
17.


3.        American Society of Mechanical Engineers, "Code on Nuclear Air and Gas Treatment,"
National Fire Protection Association, (NFPA) 90A, Standard for the Installation of Air Conditioning and Ventilation Systems, National Fire Codes, 2002, Quincy, MA.6
          ASME/ANSI AG-1-1997.
18.


4.        American Society for Testing and Materials, "Standard Test Methods for Nuclear-Grade Activated Carbon," ASTM Standard D3803-1989. Reapproved 1995.
American Society for Testing and Materials (ASTM) D3803-1991 (Reaffirmed 2014),  
Standard Test Methods for Nuclear-Grade Activated Carbon, ASTM International, West Conshohocken, PA.7
19.


5.        C. A. Burchsted, J. E. Kahn, and A. B. Fuller, "Nuclear Air Cleaning Handbook," Oak Ridge National Laboratory, ERDA 76-21, March 31, 1976.1
NRC, Management Directive 8.4, Management of Facility-specific Backfitting and Information Collection, Washington DC.
6.        USNRC, "Information Relevant to Ensuring that Occupational Radiation Exposures at Nuclear Power Stations Will Be As Low As Is Reasonably Achievable," Regulatory Guide
          8.8, Revision 3, June 1978.2
7.        American Society of Mechanical Engineers, Section HA, Housings, of "Code on Nuclear Air and Gas Treatment," ASME AG-1a-2000, Addenda to ASME AG-1-1997, December
          2000.


8.        J.K. Fretthold, HEPA Service Life Tests-Effects-Recommendations at Department of Energy Rocky Flats Environmental Technology Site, Proceedings of the 25th DOE/NRC
20.
          Nuclear Air Cleaning and Treatment Conference, NUREG/CP-0167, April 1999.3
1 Copies may be purchased from the National Technical Information Service by writing NTIS, 5285 Port Royal Road, Springfield, VA 22161; telephone (703)487-4650; online <http://www.ntis.gov/ordernow>.
2 Single copies of regulatory guides, both active and draft, may be obtained free of charge by writing the Reproduction and Distribution Services Section, OCIO, USNRC, Washington, DC 20555-0001, or by fax to (301)415-2289, or by email to
<DISTRIBUTION@NRC.GOV>. Active guides may also be purchased from the National Technical Information Service on a standing order basis. Details on this service may be obtained by writing NTIS, 5285 Port Royal Road, Springfield, VA 22161;
telephone (800)553-6847; online <http://www.ntis.gov/ordernow>. Copies of certain guides and many other NRC documents are available electronically on the internet at NRCs home page at <WWW.NRC.GOV> in the Reference Library. Documents are also available through the Electronic Reading Room (NRCs ADAMS document system, or PARS) at the same web site.


3 Copies are available at current rates from the U.S. Government Printing Office, P.O. Box 37082, Washington, DC 20402-9328 (telephone (202)512-1800); or from the National Technical Information Service at 5285 Port Royal Road, Springfield, VA
NRC, NUREG-1409, Backfitting Guidelines, Washington DC.
22161; (telephone (800)553-6847; <http://www.ntis.gov/ordernow>). Copies are available for inspection or copying for a fee from the NRC Public Document Room at 11555 Rockville Pike, Rockville, MD; the PDRs mailing address is USNRC PDR,
Washington, DC 20555; telephone (301)415-4737 or (800)397-4209; fax (301)415-3548; email is PDR@NRC.GOV .
                                                            1.140-14


9.        NRC Information Notice 99-01, Deterioration of High-Efficiency Particulate Air Filters in a Pressurized Water Reactor Containment Fan Cooler Unit, January 20, 1999.4
5 Copies of International Atomic Energy Agency (IAEA) documents may be obtained through their Web site: 
10.      NRC Information Notice 99-34, Potential Fire Hazards in the Use of Polyalphaolefin in Testing of Air Filters, December 28, 1999.4
www.IAEA.Org/ or by writing the International Atomic Energy Agency P.O. Box 100 Wagramer Strasse 5, A-1400
11.      Environmental Protection Agency, Toxic Substance Control Act (TSCA), Inventory for Commercial Use.5
Vienna, Austria. Telephone (+431) 2600-0, Fax (+431) 2600-7, or E-Mail at Official.Mail@IAEA.Org
4 Copies are available for inspection or copying for a fee from the NRC Public Document Room at 11555 Rockville Pike, Rockville, MD; the PDRs mailing address is USNRC PDR, Washington, DC 20555; telephone (301)415-4737 or (800)397-
4209; fax (301)415-3548; e-mail <PDR@NRC.GOV>.
5 Copies are available at current rates from the U.S. Government Printing Office, P.O. Box 37082, Washington, DC 20402-9328 (telephone (202)512-1800); or from the National Technical Information Service 5285 Port Royal Road, Springfield, VA 22161;
(telephone (800)553-6847; <http://www.ntis.gov/ordernow>.
                                                              1.140-15


VALUE/IMPACT STATEMENT
6 Copies of the National Fire Protection Association (NFPA) may be purchased from the NFPA, 1 Batterymarch Park, Quincy, Massachusetts; telephone (800) 344-3555. Purchase information is available through the NFPA Web-based store at http://www.nfpa.org/Catalog/.  
        A value/impact statement was published with the draft of this guide when it was issued for public comment (Task DG-1103, October 2000). No changes were necessary, so a separate value/impact statement for this regulatory guide has not been prepared. This regulatory guide does not require a backfit analysis as described in 10 CFR 50.109(c) because it does not impose a new or amended provision in the NRCs rules and regulations. A copy of the value/impact statement (ADAMS Accession Number ML003756467) is available for inspection or copying for a fee in the NRCs Public Document Room at 11555 Rockville Pike, Rockville, MD; the PDRs mailing address is USNRC PDR, Washington, DC 20555; telephone (301)415-4737 or (800)397-4209; fax
7 Copies of American Society for Testing and Materials (ASTM) standards may be purchased from ASTM, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, Pennsylvania 19428-2959; telephone (610) 832-9585. Purchase information is available through the ASTM Web site at http://www.astm.org.}}
(301)415-3548; email is <PDR@NRC.GOV>.
                                              1.140-16}}


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Revision as of 02:27, 10 January 2025

Design, Inspection, and Testing Criteria for Air Filtration and Adsorption Units of Normal Atmosphere Cleanup Systems in Light-Water-Cooled Nuclear Power Plants
ML16070A277
Person / Time
Issue date: 08/31/2016
From:
Office of Nuclear Regulatory Research
To:
Burton S
Shared Package
ML16068A291 List:
References
RG 1.140, Rev. 3 DG-1280
Download: ML16070A277 (19)


U.S. NUCLEAR REGULATORY COMMISSION

August 2016 OFFICE OF NUCLEAR REGULATORY RESEARCH

Revision 3 REGULATORY GUIDE

Technical Lead Jerome Bettle

Written suggestions regarding this guide or development of new guides may be submitted through the NRCs public Web site under the Regulatory Guides document collection of the NRC Library at http://www.nrc.gov/reading-rm/doc-collections/reg-guides/contactus.html.

Electronic copies of this RG, previous versions of this guide, and other recently issued guides are available through the NRCs public Web site under the Regulatory Guides document collection of the NRC Library at http://www.nrc.gov/reading-rm/doc-collections/. The regulatory guide is also available through the NRCs Agencywide Documents Access and Management System (ADAMS) at http://www.nrc.gov/reading-rm/adams.html, under ADAMS Accession No. ML16070A277. The regulatory analysis may be found in ADAMS under Accession No. ML16082A538 and the staff responses to the public comments on DG-1280 may be found under ADAMS

Accession No. ML16070A279.

REGULATORY GUIDE 1.140

(Draft was issued as DG-1280, dated June 2012)

DESIGN, INSPECTION, AND TESTING CRITERIA FOR AIR

FILTRATION AND ADSORPTION UNITS OF NORMAL

ATMOSPHERE CLEANUP SYSTEMS IN

LIGHT-WATER-COOLED NUCLEAR POWER PLANTS

A. INTRODUCTION

Purpose This regulatory guide (RG) describes a method that the staff of the U.S. Nuclear Regulatory Commission (NRC) considers acceptable to implement regulatory requirements with regard to the design, inspection, and testing of normal atmosphere cleanup systems for controlling releases of airborne radioactive materials to the environment during normal operations, including anticipated operational occurrences. This guide applies to all types of nuclear power plants that use water as the primary means of cooling.

Applicability This RG applies to all holders of and applicants for operating licenses for nuclear power reactors under the provisions of Title 10 of the Code of Federal Regulations (10 CFR) Part 50, Domestic Licensing of Production and Utilization Facilities (Ref. 1), and all holders of and applicants for a power reactor combined license, standard design approval, or manufacturing license under 10 CFR Part 52, Licenses, Certifications, and Approvals for Nuclear Power Plants (Ref 2).

Applicable Regulations

Title 10, of the Code of Federal Regulations, Part 50, Domestic Licensing of Production and Utilization Facilities (10 CFR Part 50) and the associated appendices establish the requirements and design criteria for atmospheric cleanup systems.

o 10 CFR 50.34a and 50.36a, which relate to information that must be provided by applicants regarding how radioactive dose in effluents will be maintained as low as reasonably achievable (ALARA).

RG 1.140, Rev. 3, Page 2

o 10 CFR Part 50, Appendix I, "Numerical Guides for Design Objectives and Limiting Conditions for Operation To Meet the Criterion As Low As Is Reasonably Achievable for Radioactive Material in Light-Water-Cooled Nuclear Power Reactor Effluents,"

which provides numerical guidance on design objectives for light-water-cooled nuclear power reactors to meet the requirements that radioactive material in effluents released to unrestricted areas be kept as low as is reasonably achievable.

10 CFR 20.1406, Minimization of contamination (Ref. 3), which requires licensees, to the extent practical, to conduct operations to minimize the introduction of residual radioactivity into the site, including the subsurface, and requires applicants to describe in their applications how facility design and procedures for operation will minimize, to the extent practicable, contamination of the facility and the environment, facilitate eventual decommissioning, and minimize, to the extent practicable, the generation of radioactive waste.

Related Guidance

Regulatory Guide 1.52, Design, Inspection, and Testing Criteria for Air Filtration and Adsorption Units of Post-Accident Engineered-Safety-Feature Atmosphere Cleanup Systems in Light-Water-Cooled Nuclear Power Plants (Ref. 4), provides guidance for the engineered safety feature (ESF) systems.

RG 1.143, Design Guidance for Radioactive Waste Management Systems, Structures and Components Installed in Light-Water-Cooled Nuclear Reactor Power Plants (Ref. 5), describes systems handling of radioactive materials in liquids, gaseous and solid collection systems that include construction of structures.

RG 4.21, Minimization of Contamination and Radioactive Waste Generation: Life Cycle Planning (Ref. 6), gives guidance for design of facilities to minimize contamination of the facility and the environment, and to minimize the generation of waste.

NUREG-0800 Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants: LWR Edition (Ref. 7), gives NRC review criteria for meeting the requirements of nuclear power plants.

Purpose of Regulatory Guides The NRC issues RGs to describe to the public methods that the staff considers acceptable for use in implementing specific parts of the agencys regulations, to explain techniques that the staff uses in evaluating specific problems or postulated accidents, and to provide guidance to applicants. Regulatory guides are not substitutes for regulations and compliance with them is not required. Methods and solutions that differ from those set forth in regulatory guides will be deemed acceptable if they provide a basis for the findings required for the issuance or continuance of a permit or license by the Commission.

Paper Reduction Act

This RG contains and references information collections covered by 10 CFR Parts 50 and 52 that are subject to the Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et seq.). These information collections were approved by the Office of Management and Budget (OMB), control numbers 3150-0011 and 3150-0151.

Public Protection Notification

RG 1.140, Rev. 3, Page 3

The NRC may not conduct or sponsor, and a person is not required to respond to, a request for information or an information collection requirement unless the requesting document displays a currently valid OMB control number.

RG 1.140, Rev. 3, Page 4

B. DISCUSSION

Reason for Revision This revision of the guide (Revision 3) addresses changes to the referenced industry standards, which provide comprehensive test and inspection requirements. Specifically, this guide is revised to address changes to the referenced industry standards since the NRC issued Revision 2 of RG 1.140 in June 2001. The American Society of Mechanical Engineers (ASME) Committee on Nuclear Air and Gas Treatment (CONAGT) revised and expanded the scope of equipment covered by ASME-AG-1, Code on Nuclear Air and Gas Treatment (Ref. 8), which the staff previously endorsed in RG 1.140. The revision to ASME-AG-1b consolidated some requirements from ASME-N509, Nuclear Power Plant Air Cleaning Units and Components (Ref. 9); ASME-N510, Testing of Nuclear Air-Treatment Systems (Ref. 10);

and other documents previously endorsed by the staff in RG 1.140. In addition, CONAGT developed and published a new standard, ASME N511-2007, Inservice Testing of Nuclear Air Treatment, Heating Ventilation and Air Conditioning Systems (Ref. 11).

Background

10 CFR Part 50, Domestic Licensing of Production and Utilization Facilities, Appendix A,

General Design Criteria for Nuclear Power Plants, General Design Criterion (GDC) 60, Control of Releases of Radioactive Materials to the Environment, requires in part, that a facilitys design include the means to control the release of radioactive materials in gaseous effluents. In addition, GDC 61, Fuel Storage and Handling and Radioactivity Control, requires in part, that fuel storage and handling, radioactive waste, and other systems which may contain radioactivity are designed with appropriate containment, confinement, and filtering systems. Title 10 CFR 50.34a, Design Objectives for Equipment To Control Releases of Radioactive Material in EffluentsNuclear Power Reactors, and 10 CFR 50.36a, Technical Specifications on Effluents from Nuclear Power Reactors, requires in part, that means be employed to ensure that the release of radioactive material to unrestricted areas during normal reactor operation, including during expected operational occurrences, is kept as low as reasonably achievable.

10 CFR 50.34a and 50.36a provide guidance and numerical values for design objectives to help applicants for new reactors and nuclear power plant license holders meet the requirements of 10 CFR Part

50, Appendix I, "Numerical Guides for Design Objectives and Limiting Conditions for Operation To Meet the Criterion As Low As Is Reasonably Achievable (ALARA) for Radioactive Material in Light- Water- Cooled Nuclear Power Reactor Effluents." In addition to complying with the design objectives and ALARA provisions,Section II.D of Appendix I requires that additional radwaste equipment of reasonably demonstrated technology be installed if it results in a reduction of population doses within a

50-mile (80-km) radius from the power plant when added to the system in order of diminishing favorable cost-benefit return. The requirements of this Paragraph D need not be complied with by persons who have filed applications for construction permits which were docketed on or after January 2, 1971, and prior to June 4, 1976, if the radwaste systems and equipment described in the preliminary or final safety analysis report and amendments satisfy the Guides on Design Objectives for Light-Water-Cooled Nuclear Power Reactors proposed in the Concluding Statement of Position of the Regulatory Staff in Docket-RM-50-2 dated February 20, 1974, pp. 25-30, reproduced in the Annex to this Appendix I.

The design of the normal atmosphere cleanup systems of light-water-cooled nuclear power plants includes particulate filtration and radioiodine adsorption units to reduce the quantities of radioactive materials in gaseous effluents released from primary containment or auxiliary building atmospheres during normal operations, including anticipated operational occurrences. These systems operate to meet the as low as reasonably achievable requirements of 10 CFR 50.34a and 10 CFR 50.36

a. Auxiliary

RG 1.140, Rev. 3, Page 5

buildings can include those referred to as the secondary containment building, turbine building, radwaste building, and fuel handling building.

Normal atmospheric cleanup systems are generally designed to operate continuously under normal environmental conditions, such as inlet radioiodine activity levels up to 37 millibecquerels per cubic centimeter (16.4 picocuries per cubic inch), relative humidity up to 100 percent, temperatures up to

52 degrees Celsius (125 degrees Fahrenheit), and normal atmospheric pressure. System design, inspection, and testing anticipates the buildup of radioactive particulates and radioiodine and minimizes consequential degradation of system performance. The ambient environment both within and surrounding the facility may affect the performance of the normal atmosphere cleanup systems. Industrial contaminants and pollutants, as well as temperature and relative humidity, contribute to the aging and weathering of filters and adsorbers and reduce their reliability.

Components of the normal atmosphere cleanup systems are designed for reliable performance under the expected operating conditions. Initial and inservice testing and proper maintenance are also primary factors in ensuring system reliability. Component and system design support and facilitate testing, inspection, and maintenance through built-in layout and accessibility features.

Section FF of ASME AG-1b-2009, provides the terminology and describes the characteristics of adsorbent media. The only adsorbent media discussed in this RG is impregnated activated carbon because it is used nearly to the exclusion of all others by NRC licensees.

In addition to filtration systems used to treat exhausts from containment and auxiliary building atmospheres, cleanup systems are also used to treat process streams from power cycle waste offgas systems. These systems treat radioactive process and effluent streams characterized by the presence of noble gases, radioiodines, and mixtures of hydrogen and oxygen gases. These systems also operate to meet the as low as reasonably achievable requirements of 10 CFR 50.34a and 10 CFR 50.36a. The design of treatment systems used in power cycle waste offgas systems are characterized by the presence of hydrogen recombiners, compressors, delay tanks or vessels either empty or containing large amounts of activated carbon (e.g., hundreds of kilograms or thousands of pounds in PWRs or tens of thousands of kilograms/pounds in BWRs).

Harmonization with International Standards The International Atomic Energy Agency (IAEA) has established a series of safety guides and standards constituting a high level of safety for protecting people and the environment. IAEA safety guides present international good practices and increasingly reflects best practices to help users striving to achieve high levels of safety. Pertinent to this regulatory guide, IAEA Safety Guide NS-G-1.10, Design of Reactor Containment Systems for Nuclear Power Plants (Ref. 12), addresses the requirements of management of radionuclides leaking through a containment of Nuclear Power Plants. Additionally, IAEA Safety Guide NS-G-2.7, Radiation Protection and Radioactive Waste Management in the Operation of Nuclear Power Plants (Ref. 13), provides recommendations as to how to develop radiation protection programs. IAEA Safety Standard SSR-2/1, Safety of Nuclear Power Plants: Design (Ref. 14), addresses controlling the release of radioactive gases into the environment. The NRC has an interest in facilitating the harmonization of standards used domestically and internationally. This RG is consistent with the recommendations and guidance in the IAEA Safety Guides NS-G-1.10, NG-G-2.7 and SSR-2/1.

RG 1.140, Rev. 3, Page 6

Documents Discussed in Staff Regulatory Guidance

This RG endorses the use of one or more codes or standards developed by external organizations, and other third party guidance documents. These codes, standards and third party guidance documents may contain references to other codes, standards or third party guidance documents (secondary references). If a secondary reference has itself been incorporated by reference into NRC regulations as a requirement, then licensees and applicants must comply with that standard as set forth in the regulation. If the secondary reference has been endorsed in a RG as an acceptable approach for meeting an NRC

requirement, then the standard constitutes a method acceptable to the NRC staff for meeting that regulatory requirement as described in the specific RG. If the secondary reference has neither been incorporated by reference into NRC regulations nor endorsed in a RG, then the secondary reference is neither a legally-binding requirement nor a generic NRC approved acceptable approach for meeting an NRC requirement. However, licensees and applicants may consider and use the information in the secondary reference, if appropriately justified, consistent with current regulatory practice, and consistent with applicable NRC requirements.

RG 1.140, Rev. 3, Page 7

C. STAFF REGULATORY GUIDANCE

This section describes the methods and approves for use industry guidance, with clarifications or exceptions, which the NRC staff considers acceptable to implement regulatory requirements with regard to the design, inspection, and testing of normal atmosphere cleanup systems for controlling releases of airborne radioactive materials to the environment during normal operations, including anticipated operational occurrences.

1.

General Design and Testing Criteria American Society of Mechanical Engineers code, ASME AG-1-2009, including 2010 Addenda

1a and 2011 Addenda 1b (i.e., ASME AG-1b-2009), and ASME N511-2007, provides guidance that is acceptable to the NRC staff for the design, construction, acceptance testing, quality assurance, and inservice testing of normal atmosphere cleanup systems and components. Normal atmosphere cleanup systems designed to ASME N509-2002 (Reaffirmed 2008), (or its earlier versions), and tested to ASME

N510-2007, (or its earlier versions), are also considered adequate to protect public health and safety.

2.

Environmental Design Criteria a.

Design of normal atmosphere cleanup systems should be based on the anticipated range of operating parameters of temperature, pressure, relative humidity, and radiation levels during normal plant operations, including anticipated operational occurrences.

b.

Normal atmosphere cleanup system operation should not degrade the operation or capability of any safety system required to operate after a design-basis accident.

c.

Design of normal atmosphere cleanup systems should consider any reasonably expected significant contaminants, such as chemicals, dusts, or other particulate matter that could degrade the systems operation or capability.

d.

For power cycle waste offgas systems relying on activated carbon delay tanks or beds, the above environmental design criteria are deemed applicable, but should be evaluated and applied taking into consideration the systems specific design features.

3.

System Design Criteria

Normal atmospheric cleanup systems should be designed in accordance with ASME AG-1b-2009 as modified and supplemented by the following:

a.

Normal atmosphere cleanup systems need not be redundant or designed to seismic Category I requirements, but they should consist of at least the following components:

(1)

high-efficiency particulate air (HEPA) filters upstream of adsorbers;

(2)

iodine adsorbers (typically impregnated activated carbon), if iodine removal from the airstream is anticipated;

(3)

fans;

(4)

interspersed ducts, dampers, and instrumentation;

RG 1.140, Rev. 3, Page 8

(5)

prefilters upstream of HEPA filters, if needed to reduce particulate loading of the HEPA filters and achieve an acceptable service life;

(6)

postfilters downstream of adsorbers, if needed to retain carbon fines; and

(7)

heating elements or cooling coils, or both, if necessary to control humidity before filtration.

b.

The volumetric airflow rate of a single filtration unit should be limited to 850 cubic meters (30,000 cubic feet) per minute unless reliable in-place testing can be assured. If a higher flow capacity is needed, consider a system design with multiple, parallel units.

c.

Normal atmosphere cleanup systems should be provided with instrumentation recommended in Section IA of ASME AG-1b-2009 for monitoring and alarming pertinent airflow rates and pressure drops.

d.

Normal atmosphere cleanup systems design should limit personnel radiation exposure by incorporation of features that facilitate inspection, testing, and maintenance consistent with the guidance of RG 8.8, Information Relevant to Ensuring that Occupational Radiation Exposures at Nuclear Power Stations Will Be As Low As Is Reasonably Achievable (Ref. 15).

e.

Outdoor air intake openings should be equipped with louvers, grills, screens, or similar protective devices to minimize the adverse effects of high winds, rain, snow, ice, and other debris on system operation. Outdoor air intake openings should be located to minimize the effects of onsite sources of contaminants, such as diesel generator exhaust.

System design should consider potential airborne contaminants from offsite sources, such as nearby industrial facility discharges of dusts, combustion particulates and gases, dust storms, or salt spray particulate from nearby oceans or bays.

f.

Normal atmosphere cleanup system housings and ductwork should be designed to limit system total leakage rate, as defined in Article SA-4500 of ASME AG-1b-2009. Duct and housing leak tests should be performed consistent with Section TA of ASME AG-1b-

2009.

g.

For power cycle waste offgas systems relying on activated carbon delay tanks or beds, the above system design criteria are deemed applicable, but should be evaluated and applied taking into consideration the systems specific design features.

4.

Component Design Criteria and Qualification Testing

Components of normal atmosphere cleanup systems should be designed, constructed, and tested in accordance with Division II of ASME AG-1b-2009, as modified and supplemented by the following:

a.

Prefilters should be designed, constructed, and tested consistent with Sections FB or FJ of ASME AG-1b-2009.

b.

Air heaters should be designed, constructed, and tested consistent with Section CA of ASME AG-1b-2009.

RG 1.140, Rev. 3, Page 9

c.

HEPA filters should be designed, constructed, and tested consistent with Sections FC of ASME AG-1b-2009. HEPA filters should be compatible with the chemical and physical composition and physical conditions of the air stream. Each HEPA filter should be tested for penetration of a challenge aerosol, such as dioctyl phthalate or 4-centistoke poly- alpha olephin, in accordance with Section TA of ASME AG-1b-2009.

d.

HEPA and Type II adsorber cell mounting frames should be designed and constructed in accordance with Section FG of ASME AG-1b-2009.

e.

Filter and adsorber sections should be arranged in accordance with Section HA of ASME AG-1b-2009.

f.

Filter housings, including floors and doors, and electrical conduits, drains, and other piping installed inside filter housings should be designed and constructed in accordance with Section HA of ASME AG-1b-2009.

g.

If the relative humidity of the atmosphere entering the air cleanup system can be expected to exceed 70 percent during normal operation, the design should include heaters or cooling coils, or both, to maintain relative humidity at or below 70 percent to ensure adsorption unit efficiency. Heaters should be designed, constructed, and tested in accordance with Section CA of ASME AG-1b-2009.

h.

Adsorber cells should be designed, constructed, and tested in accordance with Section FD

for Type II or Section FE for Type III or Section FH of ASME AG-1b-2009 for Type IV

adsorber cells.

(1)

Design of an adsorber section should consider possible iodine desorption and adsorbent autoignition that may result from radioactivity-induced heat in the adsorbent and concomitant temperature rise. If needed, prevention and mitigation features could include low-flow air or inert gas bleed, cooling coils, cleanup unit isolation, or water sprays.

(2)

If a water-based fire suppression or prevention (cooling) system is installed in a normal atmosphere cleanup system housing, it should be designed for manual actuation unless a reasonable possibility exists that iodine desorption and adsorbent autoignition could occur in the housing. If autoignition is a reasonable possibility, the fire suppression system should have both manual and automatic actuation. The fire suppression system should use open spray nozzles of sufficient size, number, and location to provide complete coverage over the entire surface of the combustible filter/adsorber media. The fire system should be hard piped and supplied with a reliable source of water of adequate pressure and flow.

Location of the water supply manual actuation device should be remote from the cleanup system housing and consistent with the guidance of RG 8.8. Reliable mechanical or electrical detection devices sensing temperature, smoke, carbon monoxide, or other indications of fire ignition should be included in the system for manual and automatic actuation methods. Monitoring indicators for these detector outputs should be remote from the system housings and consistent with the guidance of RG 8.8 and support the manual actuation capability. Cross- zoning of detectors may be used for automatic actuation.

RG 1.140, Rev. 3, Page 10

(3)

For portions of atmospheric clean up systems and power cycle off gas systems (such as filter housings, delay tanks or beds, and low-points in ductwork), the design should consider features to collect and drain accumulated water from various sources. The presence and accumulation of water within portions of these systems may be attributed to condensation and from water-based fire suppression systems, when triggered. The design should provide the means to collect and route water to the appropriate radioactive waste management system given that the water would entrain radioactive materials present in such systems.

(4)

The design of water collection systems and drains should consider the requirements of 10 CFR 20.1406 in minimizing the contamination of plant facilities and the environment. Additional guidance supporting 10 CFR 20.1406 is presented in:

1. Regulatory Guide 1.143, which describes systems handling of radioactive materials in liquids, gaseous and solid collection systems that include construction of structures. Further, RG 4.21 gives guidance for design of facilities to minimize contamination of the facility and the environment, and the generation of waste.

2. NUREG-0800 gives NRC review criteria for nuclear power plants.

3. Nuclear Energy Institute (NEI) technical report NEI 08-08A Guidance for Life Cycle Minimization of Contamination (Ref. 16), provides a method for licensees to describe operational policies and operational programs to meet the programmatic requirements of 10 CFR Part 20.1406(a) and (b) for life cycle minimization of contamination. Meeting these requirements is achieved, in part, by addressing the applicable regulatory position elements of RG 4.21.

The main objective of the regulations and NRC guidance is to avoid unmonitored and uncontrolled releases of radioactive materials on the site and in uncontrolled areas, and provide information that can be used to assess potential radiological hazards.

i.

The adsorber section of the normal atmosphere cleanup system may contain any adsorbent material demonstrated to remove gaseous iodine (elemental iodine and organic iodides) from air with the required efficiency or better.

(1)

Each original or replacement batch or lot of impregnated activated carbon media used in an adsorber section should be prepared, inspected, and tested consistent with Section FF of ASME AG-1b-2009.

(2)

If impregnated activated carbon media is used, the adsorber section design should provide for a minimum atmosphere residence time of 0.05 seconds per centimeter

(0.125 seconds per inch) of adsorbent media bed depth at rated flow.

(3)

Sections FD, FE, and FH of ASME AG-1b-2009 should be used to determine residence time.

RG 1.140, Rev. 3, Page 11

(4)

If sample (inservice test) canisters are used, their design should be consistent with Section FE of ASME AG-1b-2009 or Appendix I to ASME N509-2002.

j.

Ductwork should be designed, constructed, and tested consistent with Section SA of ASME AG-1b-2009.

k.

Duct and housing layout designs should minimize ledges, protrusions, and crevices that could collect dust and moisture and impede personnel work performance or create avoidable industrial safety hazards. Turning vanes or other airflow distribution devices should be installed where needed to achieve acceptably uniform flow profiles and support representative airflow measurements.

l.

Dampers should be designed, constructed, and tested consistent with Section DA of ASME AG-1b-2009.

m.

Fan/blower and motor, mounting, and ductwork connections should be designed, constructed, and tested consistent with Section BA for fans/blowers and Section SA of ASME AG-1b-2009 for ducts.

n.

For power cycle waste offgas systems relying on activated carbon delay tanks or beds, the above component design criteria and qualification testing are deemed applicable, but should be evaluated and applied taking into consideration the systems specific design features.

5.

Maintainability Criteria

Cleanup system design should incorporate provisions for maintenance consistent with Section HA of ASME AG-1b-2009 as modified and supplemented by the following:

a.

System design should support accessibility for inspection and maintenance. Filtration unit enclosures should provide a minimum of 0.92 meters (3 feet) from mounting frame to mounting frame between banks of components. Where components within a bank are designed for replacement, the spacing between banks should be the length of the component plus at least 0.92 meters (3 feet).

b.

Cleanup system components (i.e., HEPA filters, prefilters, and adsorbers) that are used during system construction should be replaced before the system is declared fully functional.

c.

Duct access for inspection and maintenance should be provided consistent with the guidance of Section 4.3.4 of National Fire Protection Association (NFPA) 90A,

Standard for the Installation of Air Conditioning and Ventilation Systems (Ref. 17).

d.

For power cycle waste offgas systems relying on activated carbon delay tanks or beds, the above maintainability criteria are deemed applicable, but should be evaluated and applied taking into consideration the systems specific design features.

RG 1.140, Rev. 3, Page 12

6.

In-Place Testing Criteria

Initial in-place testing of normal atmosphere cleanup systems should be performed consistent with Section TA of ASME AG-1b-2009. Periodic in-place testing of the cleanup systems and components should be performed consistent with ASME N511-2007 as modified and supplemented by the following:

a.

A visual inspection of the normal atmosphere cleanup system and all associated components should be performed consistent with Appendix I to ASME N511-2007.

b.

In-place aerosol leak tests for HEPA filters upstream from the carbon adsorbers should be performed (1) consistent with and at the frequency intervals shown in Section 5.7 and Appendix III to ASME N511-2007 , (2) after each partial or complete replacement of a HEPA filter bank, (3) following detection of, or evidence of, penetration or intrusion of water or other material into any portion of a cleanup system that may have an adverse effect on the functional capability of the filters, and (4) following painting, fire, or chemical release in any ventilation zone communicating with the system that may have an adverse effect on the functional capability of the system. The leak test should confirm a combined penetration and leakage (or bypass) of the normal atmosphere cleanup system of less than 0.05 percent of the challenge aerosol at a system-rated flow +/-10 percent to warrant a 99-percent removal efficiency for particulates.

c.

HEPA filter sections that fail to satisfy appropriate leak test criteria should be examined to determine location and cause of leaks. Adjustments, such as alignment of filter cases and tightening of filter hold-down fasteners, may be made. Defective, damaged, or torn filter media should not be repaired by patching and caulking; filters should be replaced and not repaired. After adjustments or filter replacement, the cleanup system should be retested.

d.

Cleanup system adsorbers should be in-place leak tested (1) consistent with and at the frequency intervals shown in Section 5.8 and Appendix IV to ASME N511-2007,

(2) following removal of an adsorber sample for laboratory testing if the integrity of the adsorber section is affected, (3) after each partial or complete replacement of carbon adsorber in an adsorber section, (4) following detection of, or evidence of, penetration or intrusion of water or other material into any portion of a normal atmosphere cleanup system that may have an adverse effect on the functional capability of the adsorbers, and

(5) following painting, fire, or chemical release in any ventilation zone communicating with the system that may have an adverse effect on the functional capability of the system. The leak test should confirm a combined penetration and leakage (or bypass) of the adsorber section of 0.05 percent or less of the challenge gas at a system-rated flow

+/-10 percent.

e.

Adsorber sections that fail to satisfy the appropriate leak test conditions should be examined to determine the location and cause of leaks. Adjustments, such as alignment of adsorber cells, tightening of adsorber cell hold-down fasteners, or tightening of test canister fixtures, may be made. Defective or damaged adsorber cells, mounting frames, or housings should not be temporarily repaired with patching material or caulking. After adjustments or adsorber cell replacement, the cleanup system should be retested.

f.

Painting, fire, or chemical release is not communicating with the HEPA filter or adsorber if the cleanup system is not in operation, the isolation dampers are closed, and there is no pressure differential across the filter housing. This provides reasonable

RG 1.140, Rev. 3, Page 13

assurance that air is not passing through the filters and adsorbers. Conservative, well- documented administrative controls should be implemented that define the terms painting, fire, and chemical release with respect to the potential for degrading cleanup system HEPA filters and adsorbers.

g.

If welding repairs are performed on, within, or adjacent to the cleanup system ducts, housing, or mounting frames, the HEPA filters and adsorbers should first be removed from the housing (or otherwise protected). When repairs are completed and filters and adsorbers reinstalled, the cleanup system should be visually inspected and leak tested as described in Regulatory Positions 6.a, 6.b, and 6.d of this guide.

h.

For power cycle waste offgas systems relying on activated carbon delay tanks or beds, the above in place testing criteria are deemed applicable, but should be evaluated and applied taking into consideration the systems specific design features.

7.

Laboratory Testing Criteria for Activated Carbon a.

Activated carbon adsorber sections of the cleanup system should be assigned the decontamination efficiencies given in Table 1 for radioiodine if the following conditions are met:

(1)

The adsorber section meets the conditions given in Regulatory Position 6.d of this guide.

(2)

New activated carbon meets the physical property specifications given in Regulatory Position 4.i of this guide.

(3)

Representative samples of used activated carbon pass the laboratory tests given in Table 1 of this guide.

b.

Efficiency of an activated carbon adsorber section should be determined by laboratory testing of representative samples of the activated carbon experiencing the same service conditions and the same exposure to all contaminants as the entire adsorber section. Each representative sample should be 5.1 centimeters (2 inches) or more in both length and diameter, and each sample should have the same qualification and batch test characteristics as the system adsorbent. A sufficient number of representative samples should be located in parallel with the adsorber section to allow periodic determination of system adsorbent penetration throughout its service life. Where system activated carbon adsorber is greater than 5.1 centimeters (2 inches) deep, each representative sampling should consist of an equivalent depth. Once representative samples are removed for laboratory testing, the positions they occupied should be blocked off to maintain adsorber section capability.

c.

Sampling and analysis of adsorbent should be performed (1) consistent with and at the frequency intervals shown in Sections 7 and 5.9 of ASME N511-2007, (2) following painting, fire, or chemical release in any ventilation zone communicating with the system that may have an adverse effect on the functional capability of the carbon media, and (3)

following detection of, or evidence of, penetration or intrusion of water or other material into any portion of a normal atmosphere cleanup system that may have an adverse effect on the functional capability of the adsorber media.

RG 1.140, Rev. 3, Page 14

d.

Laboratory tests of representative samples of adsorbent should be conducted as indicated in Table 1 of this guide, with the test gas flow in the same direction as normal cleanup system flow unless using bulk sample extraction methods from deep bed adsorbers.

Similar laboratory tests should be performed on a sample before loading media into the adsorber section to establish a baseline for comparison with future sample test results.

The contents of an activated carbon adsorber section should be replaced with new, unused activated carbon adsorbent meeting the physical properties identified in Regulatory Position 4.i of this guide if (1) testing in accordance with Table 1 of this guide results in a representative sample failing an acceptance criterion or (2) no representative sample is available for testing.

e.

For power cycle waste offgas systems relying on activated carbon delay tanks or beds, the above laboratory testing criteria for activated carbon are deemed applicable, but should be evaluated and applied taking into consideration the systems specific design features.

Table 1. Inservice Adsorber Laboratory Tests for Activated Carbon

Activated Carbon Total Bed Depth

Maximum Assigned Activated Carbon Decontamination Efficiencies Methyl Iodide Penetration Acceptance Criterion for Representative Sample

2 inches

Elemental iodine

Organic iodide

95%

95%

Penetration 5% when tested in accordance with ASTM D3803-1991

4 inches or greater (in-series beds are treated as a single bed of aggregate depth)

Elemental iodine

Organic iodide

99%

99%

Penetration 1% when tested in accordance with ASTM D3803-1991 Activated carbon in delay tanks or beds Elemental iodine

Organic iodide

99%

99%

Penetration 1% when tested in accordance with ASTM D3803-1991

Table 1 Notes:

(1)

See Appendix I to ASME N509-2002 for the definition of a representative sample.

(2)

Credited decontamination efficiencies (a portion of which includes bypass leakage) are based on a

0.25-second residence time per 5.1 centimeter (2-inch bed depth).

(3)

The activated carbon, when new, should meet the specifications of Regulatory Position 4.i of this guide. Table 1 provides acceptable decontamination efficiencies and methyl iodide test penetrations of used activated carbon samples for laboratory testing. Testing should be performed at the frequencies specified in Regulatory Position 7.c of this guide. Testing should be performed in accordance with American Society for Testing and Materials (ASTM) D3803-1991 (Reaffirmed 2014, Standard Test Methods for Nuclear-Grade Activated Carbon (Ref. 18), with an entering air temperature of 30 degrees Celsius (86 degrees Fahrenheit) and a relative humidity of 95 percent (or 70 percent with humidity control). Humidity control can be provided by heaters, cooling coils, or an analysis that demonstrates that the air entering the installed adsorber section would be maintained less than or equal to a 70-percent relative humidity level.

RG 1.140, Rev. 3, Page 15

(4)

Organic iodide and elemental iodine are the forms of iodine that are expected to be absorbed by activated carbon. Organic iodide is more difficult for activated carbon to adsorb than elemental iodine. Therefore, the laboratory test to determine the performance of the activated carbon adsorber is based on organic iodide. Methyl iodide is the organic form of iodine that is used in the laboratory test.

(5)

For power cycle waste offgas systems relying on activated carbon delay tanks or beds, the inservice adsorber laboratory tests should confirm that the proper types of activated carbon (nuclear grade and defined mesh size) are tested for representative batches of activated carbon over the entire design inventory of the waste offgas treatment system, given the design capacity and number of delay tanks or beds.

RG 1.140, Rev. 3, Page 16

D. IMPLEMENTATION

The purpose of this section is to provide information on how applicants and licensees1 may use this guide and information regarding the NRCs plans for using this regulatory guide. In addition, it describes how the NRC staff complies with 10 CFR 50.109, Backfitting and any applicable finality provisions in 10 CFR Part 52, Licenses, Certifications, and Approvals for Nuclear Power Plants.

Use by Applicants and Licensees Applicants and licensees may voluntarily2 use the guidance in this document to demonstrate compliance with the underlying NRC regulations. Methods or solutions that differ from those described in this regulatory guide may be deemed acceptable if they provide sufficient basis and information for the NRC staff to verify that the proposed alternative demonstrates compliance with the appropriate NRC

regulations. Current licensees may continue to use guidance the NRC found acceptable for complying with the identified regulations as long as their current licensing basis remains unchanged.

Licensees may use the information in this regulatory guide for actions which do not require NRC

review and approval such as changes to a facility design under 10 CFR 50.59, Changes, Tests, and Experiments. Licensees may use the information in this regulatory guide or applicable parts to resolve regulatory or inspection issues.

Use by NRC Staff The NRC staff does not intend or approve any imposition or backfitting of the guidance in this regulatory guide. The NRC staff does not expect any existing licensee to use or commit to using the guidance in this regulatory guide, unless the licensee makes a change to its licensing basis. The NRC staff does not expect or plan to request licensees to voluntarily adopt this regulatory guide to resolve a generic regulatory issue. The NRC staff does not expect or plan to initiate NRC regulatory action which would require the use of this regulatory guide. Examples of such unplanned NRC regulatory actions include issuance of an order requiring the use of the regulatory guide, requests for information under

10 CFR 50.54(f) as to whether a licensee intends to commit to use of this regulatory guide, generic communication, or promulgation of a rule requiring the use of this regulatory guide without further backfit consideration.

During regulatory discussions on plant specific operational issues, the staff may discuss with licensees various actions consistent with staff positions in this regulatory guide, as one acceptable means of meeting the underlying NRC regulatory requirement. Such discussions would not ordinarily be considered backfitting even if prior versions of this regulatory guide are part of the licensing basis of the facility. However, unless this regulatory guide is part of the licensing basis for a facility, the staff may not represent to the licensee that the licensees failure to comply with the positions in this regulatory guide constitutes a violation.

If an existing licensee voluntarily seeks a license amendment or change and (1) the NRC staffs consideration of the request involves a regulatory issue directly relevant to this new or revised regulatory guide and (2) the specific subject matter of this regulatory guide is an essential consideration in the staffs

1 In this section, licensees refers to licensees of nuclear power plants under 10 CFR Parts 50 and 52; and the term applicants, refers to applicants for licenses and permits for (or relating to) nuclear power plants under 10 CFR Parts

50 and 52, and applicants for standard design approvals and standard design certifications under 10 CFR Part 52.

2 In this section, voluntary and voluntarily means that the licensee is seeking the action of its own accord, without the force of a legally binding requirement or an NRC representation of further licensing or enforcement action.

RG 1.140, Rev. 3, Page 17

determination of the acceptability of the licensees request, then the staff may request that the licensee either follow the guidance in this regulatory guide or provide an equivalent alternative process that demonstrates compliance with the underlying NRC regulatory requirements. This is not considered backfitting as defined in 10 CFR 50.109(a)(1) or a violation of any of the issue finality provisions in 10

CFR Part 52.

Additionally, an existing applicant may be required to comply to new rules, orders, or guidance if

10 CFR 50.109(a)(3) applies.

If a licensee believes that the NRC is either using this regulatory guide or requesting or requiring the licensee to implement the methods or processes in this regulatory guide in a manner inconsistent with the discussion in this Implementation section, then the licensee may file a backfit appeal with the NRC in accordance with the guidance in NRC Management Directive 8.4, Management of Facility-Specific Backfitting and Information Collection (Ref. 19) and NUREG-1409, Backfitting Guidelines, (Ref. 20).

RG 1.140, Rev. 3, Page 18

REFERENCES3

1.

U.S. Code of Federal Regulations (CFR) Domestic Licensing of Production and Utilization Facilities, Part 50, Chapter 1, Title 10, Energy, Washington, DC.

2.

CFR, Licenses, Certifications, and Approvals for Nuclear Power Plants, Part 52, Chapter 1, Title 10, Energy, Washington, DC.

3.

CFR, 10 CFR 20.1406, Minimization of contamination, U.S. Nuclear Regulatory Commission, Washington DC.

4.

Nuclear Regulatory Commission (NRC), Regulatory Guide 1.52, Design, Inspection, and Testing Criteria for Air Filtration and Adsorption Units of Post-Accident Engineered-Safety- Feature Atmosphere Cleanup Systems in Light-Water-Cooled Nuclear Power Plants, Washington, DC.

5.

NRC, Regulatory Guide 1.143, Design Guidance for Radioactive Waste Management Systems, Structures and Components Installed in Light-Water-Cooled Nuclear Reactor Power Plants, Washington, DC.

6.

NRC, Regulatory Guide 4.21, Minimization of Contamination and Radioactive Waste Generation: Life Cycle Planning, Washington, DC.

7.

NRC, NUREG-0800 Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants: LWR Edition

8.

American Society of Mechanical Engineers (ASME) AG-1b-2009, Code on Nuclear Air and Gas Treatment, 2009, including 2010 Addenda 1a and 2011 Addenda 1b, American Society of Mechanical Engineers, New York, NY.4

9.

ASME N509-2002 (Reaffirmed 2008), Nuclear Power Plant Air-Cleaning Units and Components, American Society of Mechanical Engineers, New York, NY.

10.

ASME N510-2007, Testing of Nuclear Air-Treatment Systems, American Society of Mechanical Engineers, New York, NY.

11.

ASME N511-2007, Standard N511, Inservice Testing of Nuclear Air Treatment, Heating, Ventilating, and Air-Conditioning Systems, American Society of Mechanical Engineers, New York, NY.

3 Publicly available documents from the U.S. Nuclear Regulatory Commission (NRC) are available electronically through the NRC Library on the NRCs public Web site at http://www.nrc.gov/reading-rm/doc-collections/. The documents can also be viewed on-line for free or printed for a fee in the NRCs Public Document Room (PDR) at

11555 Rockville Pike, Rockville, MD; the mailing address is USNRC PDR, Washington, DC 20555; telephone (301)

415-4737 or (800) 397-4209; fax (301) 415 3548; and e-mail pdr.resource@nrc.gov.

4 Copies of American Society of Mechanical Engineers (ASME) standards may be purchased from ASME, Two Park Avenue, New York, New York 10016-5990; telephone (800) 843-2763. Purchase information is available through the ASME Web-based store at http://www.asme.org/Codes/Publications/.

RG 1.140, Rev. 3, Page 19

12.

International Atomic Energy Agency (IAEA), NS-G-1.10, Design of Reactor Containment Systems of Nuclear Power Plants, Vienna, Austria. 5

13.

IAEA, NS-G-2.7, Radiation Protection and Radioactive Waste Management in the Operation of Nuclear Power Plants, Vienna, Austria.

14.

IAEA, SSR-2/1, Safety of Nuclear Power Plants: Design, Vienna, Austria.

15.

NRC, Regulatory Guide 8.8, Information Relevant to Ensuring that Occupational Radiation Exposures at Nuclear Power Stations Will Be As Low As Is Reasonably Achievable, Washington, DC.

16.

Nuclear Energy Institute (NEI) technical report NEI 08-08A Guidance for Life Cycle Minimization of Contamination, (ADAMS Accession Number ML093220530,

ML092720253)

17.

National Fire Protection Association, (NFPA) 90A, Standard for the Installation of Air Conditioning and Ventilation Systems, National Fire Codes, 2002, Quincy, MA.6

18.

American Society for Testing and Materials (ASTM) D3803-1991 (Reaffirmed 2014),

Standard Test Methods for Nuclear-Grade Activated Carbon, ASTM International, West Conshohocken, PA.7

19.

NRC, Management Directive 8.4, Management of Facility-specific Backfitting and Information Collection, Washington DC.

20.

NRC, NUREG-1409, Backfitting Guidelines, Washington DC.

5 Copies of International Atomic Energy Agency (IAEA) documents may be obtained through their Web site:

www.IAEA.Org/ or by writing the International Atomic Energy Agency P.O. Box 100 Wagramer Strasse 5, A-1400

Vienna, Austria. Telephone (+431) 2600-0, Fax (+431) 2600-7, or E-Mail at Official.Mail@IAEA.Org

6 Copies of the National Fire Protection Association (NFPA) may be purchased from the NFPA, 1 Batterymarch Park, Quincy, Massachusetts; telephone (800) 344-3555. Purchase information is available through the NFPA Web-based store at http://www.nfpa.org/Catalog/.

7 Copies of American Society for Testing and Materials (ASTM) standards may be purchased from ASTM, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, Pennsylvania 19428-2959; telephone (610) 832-9585. Purchase information is available through the ASTM Web site at http://www.astm.org.