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4.1 Use as an Analytical Tool—Mathematical methods provide an analytical tool to be employed for many applications related to absorbed dose determinations in radiation processing. Mathematical calculations may not be used as a substitute for routine dosimetry in some applications (for example, medical device sterilization, food irradiation).4.2 Dose Calculation—Absorbed-dose calculations may be performed for a variety of photon/electron environments and irradiator geometries.4.3 Evaluate Process Effectiveness—Mathematical models may be used to evaluate the impact of changes in product composition, loading configuration, and irradiator design on dose distribution.4.4 Complement or Supplement to Dosimetry—Dose calculations may be used to establish a detailed understanding of dose distribution, providing a spatial resolution not obtainable through measurement. Calculations may be used to reduce the number of dosimeters required to characterize a procedure or process (for example, dose mapping).4.5 Alternative to Dosimetry—Dose calculations may be used when dosimetry is impractical (for example, granular materials, materials with complex geometries, material contained in a package where dosimetry is not practical or possible).4.6 Facility Design—Dose calculations are often used in the design of a new irradiator and can be used to help optimize dose distribution in an existing facility or radiation process. The use of modeling in irradiator design can be found in Refs (2-7).4.7 Validation—The validation of the model should be done through comparison with reliable and traceable dosimetric measurements. The purpose of validation is to demonstrate that the mathematical method makes reliable predictions of dose and other transport quantities. Validation compares predictions or theory to the results of an appropriate experiment. The degree of validation is commensurate with the application. Guidance is given in the documents referenced in Annex A2.4.8 Verification—Verification is the confirmation of the mathematical correctness of a computer implementation of a mathematical method. This can be done, for example, by comparing numerical results with known analytic solutions or with other computer codes that have been previously verified. Verification should be done to ensure that the simulation is appropriate for the intended application. Refer to 3.1.24.NOTE 2: Certain applications of the mathematical model deal with Operational Qualification (OQ), Performance Qualification (PQ) and process control in radiation processing such as the sterilization of healthcare products. The application and use of the mathematical model in these applications may have to meet regulatory requirements. Refer to Section 6 for prerequisites for application of a mathematical method and Section 8 for requirements before routine use of the mathematical method.4.9 Uncertainty—An absorbed dose prediction should be accompanied by an estimate of overall uncertainty, as it is with absorbed-dose measurement (refer to ISO/ASTM 51707 and JCGM100:2008 and JCGM200:2012). In many cases, absorbed-dose measurement helps to establish the uncertainty in the dose calculation.4.10 This guide should not be used as the only reference in the selection and use of mathematical models. The user is encouraged to contact individuals who are experienced in mathematical modelling and to read the relevant publications in order to select the best tool for their application. Radiation processing is an evolving field and the references cited in the annotated examples of Annex A6 are representative of the various published applications. Where a method is validated with dosimetry, it becomes a benchmark for that particular application.1.1 This guide describes different mathematical methods that may be used to calculate absorbed dose and criteria for their selection. Absorbed-dose calculations can determine the effectiveness of the radiation process, estimate the absorbed-dose distribution in product, or supplement or complement, or both, the measurement of absorbed dose.1.2 Radiation processing is an evolving field and annotated examples are provided in Annex A6 to illustrate the applications where mathematical methods have been successfully applied. While not limited by the applications cited in these examples, applications specific to neutron transport, radiation therapy and shielding design are not addressed in this document.1.3 This guide covers the calculation of radiation transport of electrons and photons with energies up to 25 MeV.1.4 The mathematical methods described include Monte Carlo, point kernel, discrete ordinate, semi-empirical and empirical methods.1.5 This guide is limited to the use of general purpose software packages for the calculation of the transport of charged or uncharged particles and photons, or both, from various types of sources of ionizing radiation. This standard is limited to the use of these software packages or other mathematical methods for the determination of spatial dose distributions for photons emitted following the decay of 137Cs or 60Co, for energetic electrons from particle accelerators, or for X-rays generated by electron accelerators.1.6 This guide assists the user in determining if mathematical methods are a useful tool. This guide may assist the user in selecting an appropriate method for calculating absorbed dose. The user must determine whether any of these mathematical methods are appropriate for the solution to their specific application and what, if any, software to apply.NOTE 1: The user is urged to apply these predictive techniques while being aware of the need for experience and also the inherent limitations of both the method and the available software. Information pertaining to availability and updates to codes for modeling radiation transport, courses, workshops and meetings can be found in Annex A1. For a basic understanding of radiation physics and a brief overview of method selection, refer to Annex A3.1.7 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 This test method is designed to provide a uniform test to assess the suitability of coatings, used in nuclear power facilities, under radiation exposure for the life of the facilities, including radiation during a DBA (Coating Service Level I areas only). Specific plant radiation exposure may exceed or be less than the amount specified in 7.2 of this standard. If required by the licensee design basis, the gamma dose used may exceed the actual anticipated plant gamma dose to account for beta dose. Coatings in Level II and III areas (outside primary containment) are expected to be exposed to lower accumulated radiation doses.1.1 This test method covers a standard procedure for evaluating the lifetime radiation tolerance of coatings to be used in nuclear power plants. This test method is applicable to Coating Service Levels I, II, and III.1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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Terminology Relating to Radiation Measurements and Dosimetry

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This specification describes the requirements for packaged, thin film medical protective gloves with radiation attenuating properties intended to protect the operator or other persons from unnecessary exposure to radiation during radiological procedures by providing an attenuating barrier to radiation. It specifies the minimum attenuation values and physical property requirements for these radiation-attenuating gloves, which must be compounded from natural rubber latex, rubber cement or synthetic polymers. This specification also covers labeling requirements.1.1 To describe the requirements for packaged protective gloves with radiation attenuating properties intended to protect the operator or other persons from unnecessary exposure to radiation during radiological procedures by providing an attenuating barrier to radiation. Minimum attenuation values will be defined.1.2 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 Indicators may be used to show that products have been exposed to a radiation source. They should be used only to provide a qualitative indication of radiation exposure and may be used to distinguish process loads that have been irradiated from unirradiated loads.NOTE 1: The use of indicators does not eliminate the need for other process-control procedures, such as quantitative dosimetry or the controlled segregation of irradiated from nonirradiated products.NOTE 2: See ISO/ASTM Standards 51608, 51649, 51702, 51939, and 51940 for information on the use of indicators in the various types of processing facilities and for unique product applications.4.2 The indicator manufacturer is obliged to supply a statement regarding the approximate dose level at which the examiner (20/20 vision), at standard illumination (unfiltered daylight, or artificial light of the spectrum and intensity defined by the proper ASTM standard), is able to determine the visual change in the indicator.1.1 This document covers procedures for using radiation-sensitive indicators (referred to hereafter as indicators) in radiation processing. These indicators may be labels, papers, inks or packaging materials which undergo a visual change when exposed to ionizing radiation (1-5).21.2 The purpose for using indicators is to determine visually whether or not a product has been irradiated, rather than to measure different dose levels.1.3 Indicators are not dosimeters and should not be used as a substitute for proper dosimetry. Information about dosimetry systems for radiation processing is provided in other ASTM and ISO/ASTM documents (see ISO/ASTM Guide 51261).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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 A variety of products and materials are irradiated with X-radiation to modify their characteristics and improve the economic value or to reduce their microbial population for health-related purposes. Dosimetry requirements might vary depending on the type and end use of the product. Some examples of irradiation applications where dosimetry may be used are:4.1.1 Sterilization of health care products;4.1.2 Treatment of food for the purpose of parasite and pathogen control, insect disinfestation, and shelf life extension;4.1.3 Disinfection of consumer products;4.1.4 Cross-linking or degradation of polymers and elastomers;4.1.5 Curing composite material;4.1.6 Polymerization of monomers and oligomer and grafting of monomers onto polymers;4.1.7 Enhancement of color in gemstones and other materials;4.1.8 Modification of characteristics of semiconductor devices; and4.1.9 Research on materials effects of irradiation.NOTE 3: Dosimetry with measurement traceability and with known measurement uncertainty is required for regulated irradiation processes, such as the sterilization of health care products and treatment of food. Dosimetry may be less important for other industrial processes, such as polymer modification, which can be evaluated by changes in the physical properties of the irradiated materials. Nevertheless, routine dosimetry may be used to monitor the reproducibility of the radiation process.4.2 Radiation processing specifications usually include a pair of absorbed-dose limits: a minimum value to ensure the intended beneficial effect and a maximum value that the product can tolerate while still meeting its functional or regulatory specifications. For a given application, one or both of these values may be prescribed by process specifications or regulations. Knowledge of the dose distribution within irradiated material is essential to help meet these requirements. Dosimetry is essential to the radiation process since it is used to determine both of these limits and to confirm that the product is routinely irradiated within these limits.4.3 Several critical parameters must be controlled to obtain reproducible dose distributions in the process load. The absorbed-dose distribution within the product depends on the overall product dimensions and mass and irradiation geometry. The processing rate and dose distribution depend on the X-ray intensity, photon energy spectrum, and spatial distribution of the radiation field and conveyor speed.4.4 Before an irradiator can be used, it must be qualified (IQ, OQ) to determine its effectiveness in reproducibly delivering known, controllable absorbed doses. This involves testing the process equipment, calibrating the equipment and dosimetry system, and characterizing the magnitude, distribution and reproducibility of the absorbed dose delivered by the irradiator for a range of product densities.4.5 To ensure consistent dose delivery in a qualified irradiation process, routine process control requires procedures for routine product dosimetry and for product handling before and after the treatment, consistent product loading configuration, control and monitoring of critical process parameters, and documentation of the required activities and functions.1.1 This practice outlines the dosimetric procedures to be followed during installation qualification, operational qualification, performance qualification and routine processing at an X-ray (bremsstrahlung) irradiator. Other procedures related to operational qualification, performance qualification and routine processing that may influence absorbed dose in the product are also discussed.NOTE 1: Dosimetry is only one component of a total quality assurance program for adherence to good manufacturing practices used in radiation processing applications.NOTE 2: ISO/ASTM Practices 51649, 51818 and 51702 describe dosimetric procedures for electron beam and gamma facilities for radiation processing.1.2 For radiation sterilization of health care products, see ISO 11137-1, Sterilization of health care products – Radiation – Part 1: Requirements for development, validation and routine control of a sterilization process for medical devices. In those areas covered by ISO 11137-1, that standard takes precedence.1.3 For irradiation of food, see ISO 14470, Food irradiation – Requirements for development, validation and routine control of the process of irradiation using ionizing radiation for the treatment of food. In those areas covered by ISO 14470, that standard takes precedence.1.4 This document is one of a set of standards that provides recommendations for properly implementing and utilizing dosimetry in radiation processing. It is intended to be read in conjunction with ISO/ASTM Practice 52628, “Practice for Dosimetry in Radiation Processing”.1.5 In contrast to monoenergetic gamma radiation, the X-ray energy spectrum extends from low values (about 35 keV) up to the maximum energy of the electrons incident on the X-ray target (see Section 5 and Annex A1).1.6 Information about effective or regulatory dose limits and energy limits for X-ray applications is not within the scope of this practice.1.7 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.

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4.1 Various products and materials are routinely irradiated at pre-determined doses at electron beam facilities to preserve or modify their characteristics. Dosimetry requirements may vary depending on the radiation process and end use of the product. A partial list of processes where dosimetry may be used is given below.4.1.1 Polymerization of monomers and grafting of monomers onto polymers,4.1.2 Cross-linking or degradation of polymers,4.1.3 Curing of composite materials,4.1.4 Sterilization of health care products,4.1.5 Disinfection of consumer products,4.1.6 Food irradiation (parasite and pathogen control, insect disinfestation, and shelf-life extension),4.1.7 Control of pathogens and toxins in drinking water,4.1.8 Control of pathogens and toxins in liquid or solid waste,4.1.9 Modification of characteristics of semiconductor devices,4.1.10 Color enhancement of gemstones and other materials, and4.1.11 Research on radiation effects on materials.4.2 Dosimetry is used as a means of monitoring the irradiation process.NOTE 2: Dosimetry with measurement traceability and known uncertainty is required for regulated radiation processes such as sterilization of health care products (see ISO 11137-1 and Refs (1-36)) and preservation of food (see ISO 14470 and Ref (4)). It may be less important for other processes, such as polymer modification, which may be evaluated by changes in the physical and chemical properties of the irradiated materials. Nevertheless, routine dosimetry may be used to monitor the reproducibility of the treatment process.NOTE 3: Measured dose is often characterized as absorbed dose in water. Materials commonly found in single-use disposable medical devices and food are approximately equivalent to water in the absorption of ionizing radiation. Absorbed dose in materials other than water may be determined by applying conversion factors (5, 6).4.3 An irradiation process usually requires a minimum absorbed dose to achieve the desired effect. There may also be a maximum dose limit that the product can tolerate while still meeting its functional or regulatory specifications. Dosimetry is essential, since it is used to determine both of these limits during the research and development phase, and also to confirm that the product is routinely irradiated within these limits.4.4 The dose distribution within the product depends on process load characteristics, irradiation conditions, and operating parameters.4.5 Dosimetry systems must be calibrated with traceability to national or international standards and the measurement uncertainty must be known.4.6 Before a radiation facility is used, it must be characterized to determine its effectiveness in reproducibly delivering known, controllable doses. This involves testing and calibrating the process equipment, and dosimetry system.4.7 Before a radiation process is commenced it must be validated. This involves execution of Installation Qualification (IQ), Operational Qualification (OQ), and Performance Qualification (PQ), based on which process parameters are established that will ensure that product is irradiated within specified limits.4.8 To ensure consistent and reproducible dose delivery in a validated process, routine process control requires that documented procedures are established for activities to be carried out before, during and after irradiation, such as for ensuring consistent product loading configuration and for monitoring of critical operating parameters and routine dosimetry.1.1 This practice outlines dosimetric procedures to be followed in installation qualification (IQ), operational qualification (OQ) and performance qualifications (PQ), and routine processing at electron beam facilities.1.2 The electron beam energy range covered in this practice is between 300 keV and 25 MeV, although there are some discussions for other energies.1.3 Dosimetry is only one component of a total quality assurance program for adherence to good manufacturing practices used in radiation processing applications. Other measures besides dosimetry may be required for specific applications such as health care product sterilization and food preservation.1.4 Specific standards exist for the radiation sterilization of health care products and the irradiation of food. For the radiation sterilization of health care products, see ISO 11137-1 (Requirements) and ISO 11137-3 (Guidance on dosimetric aspects). For irradiation of food, see ISO 14470. In those areas covered by these standards, they take precedence. Information about effective or regulatory dose limits for food products is not within the scope of this practice (see ASTM Guides F1355, F1356, F1736, and F1885).1.5 This document is one of a set of standards that provides recommendations for properly implementing and utilizing dosimetry in radiation processing. It is intended to be read in conjunction with ISO/ASTM 52628, “Practice for Dosimetry in Radiation Processing”.NOTE 1: For guidance in the calibration of routine dosimetry systems, see ISO/ASTM Practice 51261. For further guidance in the use of specific dosimetry systems, see relevant ISO/ASTM Practices. For discussion of radiation dosimetry for pulsed radiation, see ICRU Report 34.1.6 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 requirements prior to use.

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4.1 Various products and materials routinely are irradiated at predetermined doses in gamma irradiation facilities to reduce their microbial population or to modify their characteristics. Dosimetry requirements may vary depending upon the irradiation application and end use of the product. Some examples of irradiation applications where dosimetry may be used are:4.1.1 Sterilization of medical devices,4.1.2 Treatment of food for the purpose of parasite and pathogen control, insect disinfestation, and shelf life extension,4.1.3 Disinfection of consumer products,4.1.4 Cross-linking or degradation of polymers and elastomers,4.1.5 Polymerization of monomers and grafting of monomers onto polymers,4.1.6 Enhancement of color in gemstones and other materials,4.1.7 Modification of characteristics of semiconductor devices, and4.1.8 Research on materials effects.NOTE 3: Dosimetry is required for regulated irradiation processes such as sterilization of medical devices and the treatment of food. It may be less important for other industrial processes, for example, polymer modification, which can be evaluated by changes in the physical and chemical properties of the irradiated materials.4.2 An irradiation process usually requires a minimum absorbed dose to achieve the intended effect. There also may be a maximum absorbed dose that the product can tolerate and still meet its functional or regulatory specifications. Dosimetry is essential to the irradiation process since it is used to determine both of these limits and to confirm that the product is routinely irradiated within these limits.4.3 The absorbed-dose distribution within the product depends on the overall product dimensions and mass, irradiation geometry, and source activity distribution.4.4 Before an irradiation facility can be used, it must be qualified to determine its effectiveness in reproducibly delivering known, controllable absorbed doses. This involves testing the process equipment, calibrating the equipment and dosimetry system, and characterizing the magnitude, distribution and reproducibility of the absorbed dose delivered by the irradiator for a range of product densities.4.5 To ensure consistent and reproducible dose delivery in a qualified process, routine process control requires documented product handling procedures before and after irradiation, consistent product loading configuration, control and monitoring of critical process parameters, routine product dosimetry and documentation of the required activities.1.1 This practice outlines the installation qualification program for an irradiator and the dosimetric procedures to be followed during operational qualification, performance qualification, and routine processing in facilities that process products with ionizing radiation from radionuclide gamma sources to ensure that product has been treated within a predetermined range of absorbed dose. Other procedures related to operational qualification, performance qualification, and routine processing that may influence absorbed dose in the product are also discussed.NOTE 1: Dosimetry is only one component of a total quality assurance program for adherence to good manufacturing practices used in radiation processing applications.NOTE 2: ISO/ASTM Practices 51818 and 51649 describe dosimetric procedures for low and high enery electron beam facilities for radiation processing and ISO/ASTM Practice 51608 describes procedures for X-ray (bremsstrahlung) facilities for radiation processing.1.2 For the radiation sterilization of health care products, see ISO 11137-1. In those areas covered by ISO 11137-1, that standard takes precedence.1.3 This document is one of a set of standards that provides recommendations for properly implementing and utilizing dosimetry in radiation processing. It is intended to be read in conjunction with ASTM Practice E2628.1.4 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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3.1 Because of the wide variety of materials being used in neutron-activation measurements, this guide is presented with the objective of bringing improved uniformity to the specific field of interest here: hardness testing of electronics primarily in critical assembly reactor environments.NOTE 2: Some of the techniques discussed are useful for 14-MeV dosimetry. See Test Method E496 for activation detector materials suitable for 14-MeV neutron effects testing.NOTE 3: The materials recommended in this guide are suitable for 252Cf or other weak source effects testing provided the fluence is sufficient to generate countable activities.3.2 This guide is organized into two overlapping subjects: the criteria used for sensor selection, and the procedures used to ensure the proper determination of activities for determination of neutron spectra. See Terminology E170 and Test Methods E181. Determination of neutron spectra with activation sensor data is discussed in Guides E721 and E944.1.1 This guide covers the selection and use of neutron-activation detector materials to be employed in neutron spectra adjustment techniques used for radiation-hardness testing of electronic semiconductor devices. Sensors are described that have been used at many radiation hardness-testing facilities, and comments are offered in table footnotes concerning the appropriateness of each reaction as judged by its cross-section accuracy, ease of use as a sensor, and by past successful application. This guide also discusses the fluence-uniformity, neutron self-shielding, and fluence-depression corrections that need to be considered in choosing the sensor thickness, the sensor covers, and the sensor locations. These considerations are relevant for the determination of neutron spectra from assemblies such as TRIGA- and Godiva-type reactors and from Californium irradiators. This guide may also be applicable to other broad energy distribution sources up to 20 MeV.NOTE 1: For definitions on terminology used in this guide, see Terminology E170.1.2 This guide also covers the measurement of the gamma-ray or beta-ray emission rates from the activation foils and other sensors as well as the calculation of the absolute specific activities of these foils. The principal measurement technique is high-resolution gamma-ray spectrometry. The activities are used in the determination of the energy-fluence spectrum of the neutron source. See Guide E721.1.3 Details of measurement and analysis are covered as follows:1.3.1 Corrections involved in measuring the sensor activities include those for finite sensor size and thickness in the calibration of the gamma-ray detector, for pulse-height analyzer deadtime and pulse-pileup losses, and for background radioactivity.1.3.2 The primary method for detector calibration that uses secondary standard gamma-ray emitting sources is considered in this guide and in Test Methods E181. In addition, an alternative method in which the sensors are activated in the known spectrum of a benchmark neutron field is discussed in Guide E1018.1.3.3 A data analysis method is presented which accounts for the following: detector efficiency; background subtraction; irradiation, waiting, and counting times; fission yields and gamma-ray branching ratios; and self-absorption of gamma rays and neutrons in the sensors.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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SNM monitors are an efficient and sensitive means of unobtrusively (without a body search) meeting the requirements of 10 CFR (Code of Federal Regulations) Part 73 or DOE Order 5632.4 (May 1986) that individuals exiting nuclear material access areas (MAAs) be searched for concealed SNM. The monitors sense radiation emitted by SNM, which is an excellent but otherwise imperceptible clue to the presence of the material. Because the monitors operate in a natural radiation environment and must detect small intensity increases as clues, the monitors must be well designed and maintained to operate without unnecessary nuisance alarms. This guide provides information on different types of monitors for searching pedestrians and vehicles. Each monitor has an inherent sensitivity at a particular nuisance alarm rate that must be low enough to maintain the monitor’credibility. Sensitivity and nuisance alarm rates are both governed by the alarm threshold so it is very important that corresponding values for both be known when measured, estimated, or specified values are discussed. Fitting SNM monitors into a facility physical protection plan must not only consider adequate sensitivity but also a sufficiently low nuisance alarm rate.1.1 This guide briefly describes the state-of-the-art of radiation monitors for detecting special nuclear material (SNM) (see 3.1.11) in order to establish the context in which to write performance standards for the monitors. This guide extracts information from technical documentation to provide information for selecting, calibrating, testing, and operating such radiation monitors when they are used for the control and protection of SNM. This guide offers an unobtrusive means of searching pedestrians, packages, and motor vehicles for concealed SNM as one part of a nuclear material control or security plan for nuclear materials. The radiation monitors can provide an efficient, sensitive, and reliable means of detecting the theft of small quantities of SNM while maintaining a low likelihood of nuisance alarms. 1.2 Dependable operation of SNM radiation monitors rests on selecting appropriate monitors for the task, operating them in a hospitable environment, and conducting an effective program to test, calibrate, and maintain them. Effective operation also requires training in the use of monitors for the security inspectors who attend them. Training is particularly important for hand-held monitoring where the inspector plays an important role in the search by scanning the instrument over pedestrians and packages or throughout a motor vehicle. 1.3 SNM radiation monitors are commercially available in three forms: 1.3.1 Small Hand-Held Monitors—These monitors may be used by an inspector to manually search pedestrians and vehicles that stop for inspection. 1.3.2 Automatic Pedestrian Monitors—These monitors are doorway or portal monitors that search pedestrians in motion as they pass between radiation detectors, or wait-in monitoring booths that make extended measurements to search pedestrians while they stop to obtain exit clearance. 1.3.3 Automatic Vehicle Monitors—These monitors are portals that monitor vehicles as they pass between radiation detectors, or vehicle monitoring stations that make extended measurements to search vehicles while they stop to obtain exit clearance. 1.4 Guidance for applying SNM monitors is available as Atomic Energy Commission/Nuclear Regulatory Commission (AEC/NRC) regulatory guides, AEC/ERDA/DOE performance standards, and more recently as handbooks and applications guides published by national laboratories under DOE sponsorship. This broad information base covering the pertinent physics, engineering practice, and equipment available for monitoring has had no automatic mechanism for periodic review and revision. This ASTM series of guides and standards will consolidate the information in a form that is reexamined and updated on a fixed schedule. 1.5 Up-to-date information on monitoring allows both nuclear facilities and regulatory agencies to be aware of the current range of monitoring alternatives. Up-to-date information also allows manufacturers to be aware of the current goals of facilities and regulators, for example, to obtain particular sensitivities at a low nuisance alarm rate with instrumentation that is dependable and easy to maintain. 1.6 This guide updates and expands the scope of NRC regulatory guides and AEC/ERDA/DOE SNM monitor performance standards using the listed publications as a technical basis. 1.7 The values stated in SI units are to be regarded as the standard. 1.8 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety problems 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.

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4.1 It is important to know the energy spectrum of the particular neutron source employed in radiation-hardness testing of electronic devices in order to relate radiation effects with device performance degradation.4.2 This guide describes the factors which must be considered when the spectrum adjustment methodology is chosen and implemented. Although the selection of sensors (foils) and the determination of responses (activities) is discussed in Guide E720, the experiment should not be divorced from the analysis. In fact, it is advantageous for the analyst conducting the spectrum determination to be closely involved with the design of the experiment to ensure that the data obtained will provide the most accurate spectrum possible. These data include the following: (1) measured responses such as the activities of foils exposed in the environment and their uncertainties, (2) response functions such as reaction cross sections along with appropriate correlations and uncertainties, (3) the geometry and materials in the test environment, and (4) a trial function or prior spectrum and its uncertainties obtained from a transport calculation or from previous experience.1.1 This guide covers procedures for determining the energy-differential fluence spectra of neutrons used in radiation-hardness testing of electronic semiconductor devices. The types of neutron sources specifically covered by this guide are fission or degraded energy fission sources used in either a steady-state or pulse mode.1.2 This guide provides guidance and criteria that can be applied during the process of choosing the spectrum adjustment methodology that is best suited to the available data and relevant for the environment being investigated.1.3 This guide is to be used in conjunction with Guide E720 to characterize neutron spectra and is used in conjunction with Practice E722 to characterize damage-related parameters normally associated with radiation-hardness testing of electronic semiconductor devices.NOTE 1: Although Guide E720 only discusses activation foil sensors, any energy-dependent neutron-responding sensor for which a response function is known may be used (1).2NOTE 2: For terminology used in this guide, see Terminology E170.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 This practice is important in characterizing the radiation hardness of electronic devices irradiated by neutrons. This characterization makes it feasible to predict some changes in operational properties of irradiated semiconductor devices or electronic systems. To facilitate uniformity of the interpretation and evaluation of results of irradiations by sources of different fluence spectra, it is convenient to reduce the incident neutron fluence from a source to a single parameter—an equivalent monoenergetic neutron fluence—applicable to a particular semiconductor material.5.2 In order to determine an equivalent monoenergetic neutron fluence, it is necessary to evaluate the displacement damage of the particular semiconductor material. Ideally, this quantity is correlated to the degradation of a specific functional performance parameter (such as current gain) of the semiconductor device or system being tested. However, this correlation has not been established unequivocally for all device types and performance parameters since, in many instances, other effects also can be important. Ionization effects produced by the incident neutron fluence or by gamma rays in a mixed neutron fluence, short-term and long-term annealing, and other factors can contribute to observed performance degradation (damage). Thus, caution should be exercised in making a correlation between calculated displacement damage and performance degradation of a given electronic device. The types of devices for which this correlation is applicable, and numerical evaluation of displacement damage are discussed in the annexes.5.3 The concept of 1-MeV equivalent fluence is widely used in the radiation-hardness testing community. It has merits and disadvantages that have been debated widely (9-12). For these reasons, specifics of a standard application of the 1-MeV equivalent fluence are presented in the annexes.1.1 This practice covers procedures for characterizing neutron fluence from a source in terms of an equivalent monoenergetic neutron fluence. It is applicable to neutron effects testing, to the development of test specifications, and to the characterization of neutron test environments. The sources may have a broad neutron-energy range, or may be mono-energetic neutron sources with energies up to 20 MeV. This practice is not applicable in cases where the predominant source of displacement damage is from neutrons of energy less than 10 keV. The relevant equivalence is in terms of a specified effect on certain physical properties of materials upon which the source spectrum is incident. In order to achieve this, knowledge of the effects of neutrons as a function of energy on the specific property of the material of interest is required. Sharp variations in the effects with neutron energy may limit the usefulness of this practice in the case of mono-energetic sources.1.2 This practice is presented in a manner to be of general application to a variety of materials and sources. Correlation between displacements (1-3)2 caused by different particles (electrons, neutrons, protons, and heavy ions) is out of the scope of this practice but is addressed in Practice E3084. In radiation-hardness testing of electronic semiconductor devices, specific materials of interest include silicon and gallium arsenide, and the neutron sources generally are test and research reactors and californium-252 irradiators.1.3 The technique involved relies on the following factors: (1) a detailed determination of the fluence spectrum of the neutron source, and (2) a knowledge of the degradation (damage) effects of neutrons as a function of energy on specific material properties.1.4 The detailed determination of the neutron fluence spectrum referred to in 1.3 need not be performed afresh for each test exposure, provided the exposure conditions are repeatable. When the spectrum determination is not repeated, a neutron fluence monitor shall be used for each test exposure.1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard, except for MeV, keV, eV, MeV·mbarn, rad(Si)·cm2, and rad(GaAs)·cm2.1.6 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 This standard provides a method to measure the level of sound power generated in a room by impacts on a given floor surface within the same room. The test results could be used to compare the relative sound power of tapping machine impact noise on various finished floor surfaces. The resulting data could be used for comparing relative levels of unwanted noise from footfalls and objects accidentally dropped on the floor.5.2 The spectrum and level of the sound power produced by floor impacts is determined by:5.2.1 The mechanical properties of the floor structure, such as its size, construction, surface, mounting or edge restraints, stiffness, or internal damping,5.2.2 The measured acoustical characteristics of the test room,5.2.3 The location of the object or device producing the impacts, and5.2.4 The nature of the impact.5.3 This test method is based on the use of a standard tapping machine of the type specified in 8.1 placed in specific positions on the floor. This machine produces a continuous series of uniform impacts at a uniform rate on a test floor and generates broadband sound pressure levels that are sufficiently high to make measurements possible with most floor types even in the presence of background noise. The tapping machine itself, however, is not designed to simulate any one type of impact, such as produced by male or female footsteps.5.4 Because of its portable design, the tapping machine does not simulate the weight of a human walker. The degree of correlation between the results of tapping machine tests in the laboratory and the subjective acceptance of floors under typical conditions of domestic impact excitation is uncertain. The correlation will depend on both the type of floor construction and the nature of the impact excitation in the building.5.5 This test method is not intended for field tests.1.1 This test method covers the laboratory measurement of impact sound radiation from floor structures using a standardized tapping machine. While the finished floor surface is usually the primary factor, it must be noted that the floor structure below the finished floor also plays a major role in the level of noise generated in the source room by impacts to the floor surface. As a result, the report must include a full description of the complete floor structure and its support (for example, perimeter support only, multiple point supports, or full continuous support like a slab on grade). It is assumed that the impact sound generated by the tapping machine in the test room is a good approximation to a diffuse sound field.1.2 Measurements may be conducted on floor structures of all kinds, including those with floating-floor or suspended ceiling elements, or both, and floor-ceiling assemblies surfaced with any type of floor-surfacing or floor-covering materials.1.3 This test method prescribes a uniform procedure for reporting laboratory test data in both one-third-octave-band and overall A-weighted sound power levels generated by the tapping machine impacts on the floor structure (test specimen).1.4 Laboratory Accreditation—The requirements for accrediting a laboratory for performing this test method are given in Annex A2.1.5 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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