27.120.30 (Fissile materials and nuclear fuel tech 标准查询与下载

ASTM C750-03 核纯级碳化硼粉末标准规范

1.1 This specification defines the chemical and physical requirements for boron carbide powder intended for a variety of nuclear applications. Because each application has a different need for impurity and boron requirements, three different chemical compositions of powder are specified. In using this specification, it is necessary to dictate which type of powder is intended to be used. In general, the intended applications for the various powder types are as follows: 1.1.1 Type 1 -For use as particulate material in nuclear reactor core applications. 1.1.2 Type 2 -Powder that will be further processed into a fabricated shape for use in a nuclear reactor core or used in non-core applications when the powder directly or indirectly may cause adverse effects on structural components, such as halide stress corrosion of stainless steel. 1.1.3 Type 3 -Powder that will be used for non-core applications or special in-core applications.

Standard Specification for Nuclear-Grade Boron Carbide Powder

ASTM C1297-03 核燃料循环材料分析用实验室分析法的鉴定标准指南

This is one of a series of guides designed to provide guidance for implementing activities that meet the requirements of a sound laboratory quality assurance program. The first of these, Guide C 1009, is an umbrella guide that provides general criteria for ensuring the quality of analytical laboratory data. Other guides provide expanded criteria in various areas affecting quality, producing a comprehensive set of criteria for controlling data quality. The approach to ensuring the quality of analytical measurements described in these guides is depicted in Fig. 1. The training and qualification of analysts is one of the elements of laboratory quality assurance presented in Guide C 1009, which provides some general criteria regarding qualification. This guide expands on those criteria to provide more comprehensive guidance for qualifying analysts. As indicated in Guide C 1009, the qualification process can vary in approach; this guide provides one such approach. This guide describes an approach to analyst qualification that is designed to be used in conjunction with a rigorous program for the qualification and control of the analytical measurement system. This requires an existing data base which defines the characteristics (precision and bias) of the system in routine use. The initial development of this data base is described in Guide C 1068. The process described here is intended only to qualify analysts when such a data base exists and the method is in control. The qualification activities described in this guide assume that the analyst is already proficient in general laboratory operations. The training or other activities that developed this proficiency are not covered in this guide. This guide describes a basic approach and principles for the qualification of laboratory analysts. Users are cautioned to ensure that the qualification program implemented meets the needs and requirements of their laboratory. FIG. 1 Quality Assurance of Analytical Laboratory Data1.1 This guide covers the qualification of analysts to perform chemical analysis or physical measurements of nuclear fuel cycle materials. The guidance is general in that it is applicable to all analytical methods, but must be applied method by method. Also, the guidance is general in that it may be applied to initial qualification or requalification.1.2 The guidance is provided in the following sections:SectionQualification Considerations4Demonstration Process5Statistical Tests61.3 This standard does not apply to maintaining qualification during routine use of a method. Maintaining qualification is included in Guide C 1210.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

Standard Guide for Qualification of Laboratory Analysts for the Analysis of Nuclear Fuel Cycle Materials

ASTM C1432-03(2008) 测定钚中杂质的标准试验方法:酸溶解,离子交换矩阵分离和感应耦合等离子体.原子发射光谱法(ICP/AES)分析

1.1 This specification covers blended uranium trioxide (UO3), U3O8, or mixtures of the two, powders that are intended for conversion into a sinterable uranium dioxide (UO2) powder by means of a direct reduction process. The UO2 powder product of the reduction process must meet the requirements of Specification C 753 and be suitable for subsequent UO2 pellet fabrication by pressing and sintering methods. This specification applies to uranium oxides with a 235U enrichment less than 5 %. 1.2 This specification includes chemical, physical, and test method requirements for uranium oxide powders as they relate to the suitability of the powder for storage, transportation, and direct reduction to UO2 powder. This specification is applicable to uranium oxide powders for such use from any source. 1.3 The scope of this specification does not comprehensively cover all provisions for preventing criticality accidents, for health and safety, or for shipping. Observance of this specification does not relieve the user of the obligation to conform to all international, national, state, and local regulations for processing, shipping, or any other way of using uranium oxide powders (see 2.2 and 2.3). 1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 1.5 The following safety hazards caveat pertains only to the test methods portion of the annexes in this specification: This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

Standard Test Method for Determination of Impurities in Plutonium: Acid Dissolution, Ion Exchange Matrix Separation, and Inductively Coupled Plasma-Atomic Emission Spectroscopic (ICP/AES) Analysis

ASTM C788-03(2009) 核纯级硝酸铀酰溶液或晶体的标准规范

1.1 This specification applies to nuclear-grade aqueous uranyl nitrate solution or crystals not exceeding 5 % 235U intended for subsequent manufacture into either UF6 (for feed to an enrichment plant) or direct conversion to uranium oxide (for use in reactors). 1.2 This specification is intended to provide the nuclear industry with a general standard for aqueous uranyl nitrate solution or crystals. It recognizes the diversity of manufacturing methods and the processes to which it is subsequently to be subjected. It is therefore anticipated that it may be necessary to include supplementary specification limits by agreement between purchaser and manufacturer. Different limits are appropriate depending on whether or not the uranyl nitrate is to be converted to UF6 for subsequent processing. 1.3 The purpose of this specification is: (a) to define the impurity and uranium isotope limits for commercial standard uranyl nitrate, and (b) to define additional limits for reprocessed uranyl nitrate (or any mixture of reprocessed and commercial standard uranyl nitrate). For such uranyl nitrates, special provisions may need to be made to ensure that no extra hazard arises to the employees, the process equipment, or the environment. 1.4 The scope of this specification does not comprehensively cover all provisions for preventing criticality accidents, for health and safety, or for shipping. Observance of this standard does not relieve the user of the obligation to conform to all international, federal, state and local regulations for processing, shipping, or any other way of using the uranyl nitrate. An example of a U.S. Government Document is the Code of Federal Regulations, Title 10, Part 50 (latest edition). 1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

Standard Specification for Nuclear-Grade Uranyl Nitrate Solution or Crystals

ASTM C1156-03(2011) 用于分析核燃料循环材料的测量方法用校准方法的确定的标准指南

Calibration is a fundamental part of making measurements and its effect on the quality of measurement data is significant. Thus, sufficient attention must be given to calibration when it is established for a measurement method so that the data produced will be acceptable. The use of an inappropriate calibration standard, inadequate instructions for calibration, and poor documentation of the calibration process are examples of circumstances that can adversely affect the validity of a calibration. Thus, the calibration process must conform to criteria established to ensure the validity of calibration results. Such criteria are given in Guide C1009, in which calibration is identified as a component of laboratory quality assurance (see Fig. 1). This guide expands upon those criteria to provide more comprehensive guidance for establishing calibration. The manner of calibration and other technical requirements for calibrating a measurement method are usually established when a method is first introduced into a laboratory, which may be through validation and qualification as defined by Guide C1068 (see Fig. 1). However, calibration involves more than the technical aspects of the calibration process. The other dimension of the process is the operational requirements that are necessary to ensure that calibration results are valid and that they are documented and verifiable should their integrity be questioned. The provisions of this guide provide those operational requirements and should be considered whenever calibration is planned and established.1.1 This guide provides the basis for establishing calibration for a measurement method typically used in an analytical chemistry laboratory analyzing nuclear materials. Guidance is included for such activities as preparing a calibration procedure, selecting a calibration standard, controlling calibrated equipment, and documenting calibration. The guide is generic and any required technical information specific for a given method must be obtained from other sources.

Standard Guide for Establishing Calibration for a Measurement Method Used to Analyze Nuclear Fuel Cycle Materials

ASTM C888-03(2014) 核纯级氧化钆(Gd203)粉末的标准规格

1.1 This specification provides the chemical and physical requirements for nuclear-grade gadolinium oxide powder intended for subsequent processing and use in nuclear fuel applications, for example, as an addition to uranium dioxide. 1.2 This specification does not include requirements for health and safety. Observance of this specification does not relieve the user of the obligation to be aware of and comply with all federal, state, and local regulations pertaining to possessing, shipping, processing, or using this material. 1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

Standard Specification for Nuclear-Grade Gadolinium Oxide 40;Gd2O341; Powder

ASTM C788-03(2015) 核纯级的硝酸铀酰溶液标准规范

1.1 This specification applies to nuclear-grade aqueous uranyl nitrate solution or crystals not exceeding 58201;% 235U intended for subsequent manufacture into either UF6 (for feed to an enrichment plant) or direct conversion to uranium oxide (for use in reactors). 1.2 This specification is intended to provide the nuclear industry with a general standard for aqueous uranyl nitrate solution or crystals. It recognizes the diversity of manufacturing methods and the processes to which it is subsequently to be subjected. It is therefore anticipated that it may be necessary to include supplementary specification limits by agreement between purchaser and manufacturer. Different limits are appropriate depending on whether or not the uranyl nitrate is to be converted to UF6 for subsequent processing. 1.3 The purpose of this specification is: (a) to define the impurity and uranium isotope limits for commercial standard uranyl nitrate, and (b) to define additional limits for reprocessed uranyl nitrate (or any mixture of reprocessed and commercial standard uranyl nitrate). For such uranyl nitrates, special provisions may need to be made to ensure that no extra hazard arises to the employees, the process equipment, or the environment. 1.4 The scope of this specification does not comprehensively cover all provisions for preventing criticality accidents, for health and safety, or for shipping. Observance of this standard does not relieve the user of the obligation to conform to all international, federal, state and local regulations for processing, shipping, or any other way of using the uranyl nitrate. An example of a U.S. Government Document is the Code of Federal Regulations, Title 10, Part 50 (latest edition). 1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

Standard Specification for Nuclear-Grade Uranyl Nitrate Solution or Crystals

ASTM C1206-02(2010) 铁(II)/铬(VI)安培计滴定法测定钚的试验方法

All plutonium materials covered in this test method are used in the preparation of nuclear-reactor fuels. In order to be suitable for this purpose, the materials must meet specified criteria for plutonium content. This test method is used to verify the plutonium content. A primary standard dichromate such as that available from National Institute of Standards and Technology (NIST) or a dichromate traceable to a primary standard such as New Brunswick Laboratory (NBL) plutonium standard, is required for this technique.1.1 This test method covers the determination of plutonium in unirradiated nuclear-grade plutonium dioxide, uranium-plutonium mixed oxides with uranium (U)/plutonium (Pu) ratios up to 21, plutonium metal, and plutonium nitrate solutions. Optimum quantities of plutonium to measure are 7 to 15 mg. 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

Standard Test Method for Plutonium by Iron (II)/Chromium (VI) Amperometric Titration

ASTM C967-02a 铀矿浓缩物的标准规范

1.1 This specification covers uranium ore concentrate containing a minimum of 65 mass % uranium. 1.2 This specification does not include requirements for health and safety. Observance of this standard does not relieve the user of the obligation to be aware of and conform to all applicable international, national, state, and local regulations pertaining to possessing, shipping, or using source nuclear material (see 2.2). 1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.

Standard Specification for Uranium Ore Concentrate

ASTM C967-02 铀精矿标准规范

1.1 This specification covers uranium ore concentrate containing a minimum of 65 mass % uranium. 1.2 This specification does not include requirements for health and safety. Observance of this standard does not relieve the user of the obligation to be aware of and conform to all applicable international, national, state, and local regulations pertaining to possessing, shipping, or using source nuclear material (see 2.2). 1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.

Standard Specification for Uranium Ore Concentrate

ASTM C1347-02 分析用铀材料制备和溶解的标准实施规程

The materials covered that must meet ASTM specifications are uranium metal and uranium oxide. Uranium materials are used as nuclear reactor fuel. For this use, these materials must meet certain criteria for uranium content, uranium-235 enrichment, and impurity content, as described in Specifications C 753 and C 776. The material is assayed for uranium to determine whether the content is as specified. Uranium alloys, refractory uranium materials, and uranium containing scrap and ash are unique uranium materials for which the user must determine the applicability of this practice. In general, these unique uranium materials are dissolved with various acid mixtures or by fusion with various fluxes.1.1 This practice covers dissolution treatments for uranium materials that are applicable to the test methods used for characterizing these materials for uranium elemental, isotopic, and impurities determinations. Dissolution treatments for the major uranium materials assayed for uranium or analyzed for other components are listed.1.2 The treatments, in order of presentation, are as follows:Procedure TitleSectionDissolution of Uranium Metal and Oxide with Nitric Acid8.1Dissolution of Uranium Oxides with Nitric Acid and Residue Treatment8.2Dissolution of Uranium-Aluminum Alloys in Hydrochloric Acid with Residue Treatment8.3Dissolution of Uranium Scrap and Ash by Leaching with Nitric Acid and Treatment of Residue by Carbonate Fusion8.4Dissolution of Refractory Uranium-Containing Material by Carbonate Fusion8.5Dissolution of Uranium-Aluminum Alloys Uranium Scrap and Ash, and RefractoryUranium-Containing Materials by Microwave Treatment8.61.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific hazards statements are given in Section 7.

Standard Practice for Preparation and Dissolution of Uranium Materials for Analysis

ASTM C1517-02 用直流电弧发射光谱分析法测定铀金属或化合物中金属杂质的标准试验方法

This test method is applicable to uranium metal, uranium oxides and compounds soluble in nitric or sulfuric acid, and uranium solutions which can be converted to uranium oxide (U3O8) in a muffle furnace. It may be used to determine the impurities in uranium compounds as listed in Specifications C 753, C 776, C 788, and C 967.1.1 This test method describes the steps necessary for the preparation and determination of impurity metals in uranium metal and uranium compounds by DC arc emission spectroscopy.1.2 The method is valid for those materials that can be dissolved in acid and/or converted to an oxide in a muffle furnace (see Practice C 1347).1.3 This method uses the carrier distillation technique to selectively carry the impurities into the arc, leaving the uranium oxide in the electrode. If it is necessary to determine the carrier metal(usually a silver or strontium, or gallium compound) as an impurity, another technique must be chosen for that element.1.4 This standard may involve hazardous materials, operations and equipment. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

Standard Test Method for Determination of Metallic Impurities in Uranium Metal or Compounds by DC-Arc Emission Spectroscopy

ASTM C1502-01 测定二氧化铀和氧化钆中氯和氟的总含量的标准试验方法

The method is designed to show whether or not the tested materials meet the specifications as given in either Specification C 753, C 776, C 888 or C 922.1.1 This test method covers the determination of chlorine and fluorine in nuclear-grade uranium dioxide (UO2) powder and pellets, nuclear grade gadolinium oxide (Gd2O3) powder and gadolinium oxide-uranium oxide (Gd2O3-UO2) powder and pellets.1.2 With a 2 gram UO2 sample size the detection limit of the method is 4 956;g/g for chlorine and 2 956;g/g for fluorine. The maximum concentration determined with a 2 gram sample is 500 956;g/g for both chlorine and fluorine. The sample size used in this test method can vary from 1 to 10 grams resulting in a corresponding change in the detection limits and range.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

Standard Test Method for Determination of Total Chlorine and Fluorine in Uranium Dioxide and Gadolinium Oxide

ASTM C1411-01 同位素分析前铀和钚离子交换分离的标准实施规程

Uranium and plutonium are used in nuclear reactor fuel and must be analyzed to insure that they meet certain criteria for isotopic composition as described in Specification C 833 and Specification C 1008. This standard practice is used to chemically separate the same mass peak interferences from uranium and plutonium and from other impurities prior to isotopic abundance determination by thermal ionization mass spectrometry. In those facilities where perchloric acid use is tolerated, the ion exchange separation procedure in Test Method E 267 may be used prior to isotopic abundance determination. Also, in those facilities where perchloric acid use is tolerated and when uranium and plutonium concentrations are to be determined as well as isotopic abundances using the thermal ionization mass spectrometer, the ion exchange separation procedure in Test Method E 267 may be used.1.1 This practice is for the ion exchange separation of uranium and plutonium from each other and from other impurities for subsequent isotopic analysis by thermal ionization mass spectrometry. Plutonium-238 and uranium-238, and plutonium-241 and americium-241, will appear as the same mass peak and must be chemically separated prior to analysis. Only high purity solutions can be analyzed reliably using thermal ionization mass spectrometry. 1.2 This standard may involve hazardous material, operations, and equipment. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

Standard Practice for the Ion Exchange Separation of Uranium and Plutonium Prior to Isotopic Analysis

ASTM C1052-01(2007) 液体六氟化铀散装取样标准实施规程

Uranium hexafluoride is normally produced and handled in large (typically 1- to 14-ton) quantities and must, therefore, be characterized by reference to representative samples. The quantities involved, physical properties, chemical reactivity, and hazardous nature of UF6 are such that for representative sampling, specially designed equipment must be used and operated in accordance with the most carefully controlled and stringent procedures. This practice indicates appropriate principles, equipment, and procedures currently in use for bulk sampling of liquid UF6. It is used by UF6 converters, enrichers, and fuel fabricators to review the effectiveness of existing procedures or as a guide to the design of equipment and procedures for future use. Other sampling procedures such as UF6 vapor sampling are not directly representative of the quality of liquid UF6. It is emphasized that this practice is not meant to address conventional or nuclear criticality safety issues.1.1 This practice covers methods for withdrawing representative samples of liquid uranium hexafluoride (UF6) from bulk quantities of the material. Such samples are used for determining compliance with the applicable commercial specification, for example Specification C 787 and Specification C 996.1.2 It is assumed that the bulk liquid UF6 being sampled comprises a single quality and quantity of material. This practice does not address any special additional arrangements that might be required for taking proportional or composite samples, or when the sampled bulk material is being added to UF6 residues already in a container ("heels recycle").1.3 The number of samples to be taken, their nominal sample weight, and their disposition shall be agreed upon between the parties.1.4 The scope of this practice does not include provisions for preventing criticality incidents.This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

Standard Practice for Bulk Sampling of Liquid Uranium Hexafluoride

ASTM C833-01(2008) 烧结二氧化铀钚丸的标准规范

1.1 This specification covers finished sintered and ground (uranium-plutonium) dioxide pellets for use in thermal reactors. It applies to uranium-plutonium dioxide pellets containing plutonium additions up to 15 % weight. This specification may not completely cover the requirements for pellets fabricated from weapons-derived plutonium. 1.2 This specification does not include (1) provisions for preventing criticality accidents or (2) requirements for health and safety. Observance of this specification does not relieve the user of the obligation to be aware of and conform to all applicable international, federal, state, and local regulations pertaining to possessing, processing, shipping, or using source or special nuclear material. Examples of U.S. government documents are Code of Federal Regulations Title 10, Part 50—Domestic Licensing of Production and Utilization Facilities; Code of Federal Regulations Title 10, Part 71—Packaging and Transportation of Radioactive Material; and Code of Federal Regulations Title 49, Part 173—General Requirements for Shipments and Packaging. 1.3 The following safety hazards caveat pertains only to the technical requirements portion, Section 4, of this specification: This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. 1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

Standard Specification for Sintered (Uranium-Plutonium) Dioxide Pellets

ASTM C761-01e1 六氟化铀的化学、质谱、核(放射性)及放射化学分析的标准试验方法

1.1 These test methods cover procedures for subsampling and for chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of uranium hexafluoride (UF6). All of these test methods are in routine use to determine conformance to UF6 specifications in the Department of Energy (DOE) gaseous diffusion plants or at other DOE installations. 1.2 The analytical procedures in this document appear 1.3 Additional test methods have been developed and are included in Appendix X 1. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. (For specific safeguard and safety consideration statements, see Section 6.)

Standard Test Methods for Chemical, Mass Spectrometric, Spectrochemical, Nuclear, and Radiochemical Analysis of Uranium Hexafluoride

ASTM C1493-01 用差动衰减系统钝化-活化中子计数法对废物中的核物质进行无损分析的标准试验方法

1.1 This test method covers a system that performs nondestructive assay (NDA) of uranium or plutonium, or both, using the active, differential die-away technique (DDT), and passive neutron coincidence counting. Results from the active and passive measurements are combined to determine the total amount of fissile and spontaneously-fissioning material in drums of scrap or waste as large as 208 L. Corrections are made to the measurements for the effects of neutron moderation and absorption, assuming that the effects are averaged over the volume of the drum and that no significant lumps of nuclear material are present. These systems are most widely used to assay low-level and transuranic waste, but may also be used for the measurement of scrap materials. While this test method is specific to the second-generation Los Alamos National Laboratory (LANL) passive-active neutron assay system, the principle applies to other DDT systems.1.1.1 In the active mode, the system measures fissile isotopes such as 235U and 239Pu. The neutrons from a pulsed, 14-MeV neutron generator are thermalized to induce fission in the assay item. Between generator pulses, the system detects prompt-fission neutrons emitted from the fissile material. The number of detected neutrons between pulses is proportional to the mass of fissile material. This method is called the differential die-away technique.1.1.2 In the passive mode, the system detects time-coincident neutrons emitted from spontaneously fissioning isotopes. The primary isotopes measured are 238Pu, 240Pu, and 242Pu; however, the system may be adapted for use on other spontaneously-fissioning isotopes as well. The number of coincident neutrons detected is proportional to the mass of spontaneously-fissioning material.1.2 The active mode is used to assay fissile material in the following ranges.1.2.1 For uranium-bearing items, the DDT can measure the 235U content in the range from 0.02 to over 100 g. Normally, the assay of items bearing only uranium is performed using matrix-specific calibrations to account for the effect of the matrix on the active signal.1.2.2 For plutonium-bearing items, the DDT method measures the 239Pu content in the range between 0.01 and 20 g.1.3 The passive mode is capable of assaying spontaneously-fissioning nuclei, over a nominal range from 0.05 to 15 g of 240Pu, or equivalent. The passive mode can also be used to measure large (for example, kg) quantities of 238U.1.4 This test method requires knowledge of the relative abundances of the plutonium or uranium isotopes to determine the total plutonium or uranium mass.1.5 This test method will give biased results when the waste form does not meet the calibration specifications and the measurement assumptions presented in this test method regarding the requirements for a homogeneous matrix, uniform source distribution, and the absence of nuclear material lumps, to the extent that they effect the measurement.1.6 The complete active and passive assay of a 208 L drum is nominally 10 min or less.1.7 Improvements to this test method have been reported (1,2,3 ,4 ). Discussions of these improvements are not included in this test method.1.8 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in Section 8.

Standard Test Method for Non-Destructive Assay of Nuclear Material in Waste by Passive and Active Neutron Counting Using a Differential Die-Away System

ASTM C1128-01(2008) 核燃料循环材料分析用操作参考材料的制备的标准指南

Certified reference materials (CRMs) prepared from nuclear materials are generally of high purity, possessing chemical stability or reproducible stoichiometry. Usually they are certified using the most unbiased and precise measurement methods available, often with more than one laboratory being involved in making certification measurements. CRMs are generally used on a national or international level, and they are at the top of the metrological hierarchy of reference materials. A graphical representation of a national nuclear measurement system is shown in Fig. 3. Working reference materials (WRMs) need to have quality characteristics that are similar to CRMs, although the rigor used to achieve those characteristics is not usually as stringent as for CRMs. Where possible, CRMs are often used to calibrate the methods used for establishing the concentration values (reference values) assigned to WRMs, thus providing traceability to CRMs as required by ISO 17025. A WRM is normally prepared for a specific application. Because of the importance of having highly reliable measurement data from nuclear materials, particularly for control and accountability purposes, CRMs are sometimes used for calibration when available. However, CRMs prepared from nuclear materials are not always available for specific applications. Thus, there may be a need for a laboratory to prepare WRMs from nuclear materials. Also, CRMs are often too expensive, or their supply is too limited for use in the quantities needed for long-term, routine use. When properly prepared, WRMs will serve equally well as CRMs for most applications, and using WRMs will preserve supplies of CRMs. Difficulties may be encountered in the preparation of RMs from nuclear materials because of the chemical and physical properties of the materials. Chemical instabilities, problems in ensuring stoichiometry, and radioactivity are factors involved, with all three factors being involved with some materials. Those preparing WRMs from nuclear materials must be aware of how these factors affect preparation, as well as being aware of the other criteria governing the preparation of reliable WRMs.1.1 This guide covers the preparation and characterization of working reference materials (WRM) that are produced by a laboratory for its own use in the analysis of nuclear materials. Guidance is provided for establishing traceability of WRMs to certified reference materials by a defined characterization process. The guidance provided is generic; it is not specific for a given material. 1.2 The information provided by this guide is found in the following sections: Section Planning 6 Preparation 7 Packaging and Storage 8 Characterization 9 Statistical Analysis10 Documentation11 1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

Standard Guide for Preparation of Working Reference Materials for Use in Analysis of Nuclear Fuel Cycle Materials

ASTM C1348-01 直接氢还原成核级二氧化铀用带低于5%的235U含量的混合氧化铀用标准规范

1.1 This specification covers blended uranium trioxide (UO3), U3O8, or mixtures of the two, powders that are intended for conversion into a sinterable uranium dioxide (UO2) powder by means of a direction reduction process. The UO2 powder product of the reduction process must meet the requirements of Specification C753 and be suitable for subsequent UO2 pellet fabrication by pressing and sintering methods. This specification applies to uranium oxides with a 235U enrichment less than 5 %. 1.2 This specification includes chemical, physical, and test method requirements for uranium oxide powders as they relate to the suitability of the powder for storage, transportation, and direct reduction of UO2 powder. This specification is applicable to uranium oxide powders for such use from any source. 1.3 The scope of this specification does not comprehensively cover all provisions for preventing criticality accidents, for health and safety, or for shipping. Observance of this specification does not relieve the user of the obligation to conform to all international, national, state, and local regulations for processing, shipping, or any other way of using uranium oxide powders (see 2.2 and 2.3). 1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 1.5 The following safety hazards caveat pertains only to the test methods portion of the annexes in this specification: This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

Standard Specification for Blended Uranium Oxides with a ²³⁵U Content of Less Than 5 % for Direct Hydrogen Reduction to Nuclear Grade Uranium Dioxide