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6.1 This test method is useful for research and development, quality assurance, regulatory compliance and specification-based acceptance.6.2 The kinetic parameters determined by this method may be used to calculate thermal hazard figures-of-merit according to Practice E1231.1.1 This test method describes the determination of the kinetic parameters of Arrhenius activation energy and pre-exponential factor using the Kissinger variable heating rate iso-conversion method (1, 2)2 and activation energy and reaction order by the Farjas method (3) for thermally unstable materials. The test method is applicable to the temperature range from 300 K to 900 K (27 °C to 627 °C).1.2 Both nth order and accelerating reactions are addressed by this method over the range of 0.5 < n < 4 and 1 < p < 4 where n is the nth order reaction order and p is the Avrami reaction order (4). Reaction orders n and p are determined by the Farjas method (3).1.3 This test method uses the same experimental conditions as Test Method E698. The Flynn/Wall/Ozawa data treatment of Test Method E698 may be simultaneously applied to these experimental results.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 Information concerning the reaction model aids in the selection of the appropriate method (and test method) for evaluation of kinetic parameters. nth order reaction may be treated by isoconversion methods such as Test Methods E698 and E2890. Autocatalytic reactions are treated by Test Methods E2070.5.2 This practice may be used in research, forensic analysis, trouble shooting, product evaluation, and hazard potential evaluation.1.1 This practice describes a procedure for determining the “model” of an exothermic reaction using differential scanning calorimetry. The procedure is typically performed on 1 mg to 3 mg specimen sizes over the temperature range from ambient to 600 °C.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, 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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5.1 This test method measures the time to extrapolated onset of an exothermic reaction under constant temperature (isothermal) conditions for reactions which have an induction period, for example, those which are catalytic, autocatalytic, or accelerating in nature or which contain reaction inhibitors.5.2 The RIT determined by this test method is an index measurement that is useful for comparing one material to another at the test temperature of interest and in the same apparatus type only.5.3 This test method is a useful adjunct to dynamic thermal tests, such as Test Method E537, which are performed under conditions in which the sample temperature is increased continuously at constant rate. Results obtained under dynamic test conditions may result in higher estimates of temperature at which an exothermic reaction initiates because the detected onset temperature is dependent upon the heating rate and because dynamic methods allow insufficient time for autocatalytic reactions to measurably affect the onset temperature.5.4 RIT values determined under a series of isothermal test conditions may be plotted as their logarithm versus the reciprocal of the absolute temperature to produce a plot, the slope of which is proportional to the activation energy of the reaction as described in Test Methods E2070.5.5 This test method may be used in research and development, manufacturing, process and quality control, and regulatory compliance.5.6 This test method is similar to that for oxidation induction time (OIT) (for example, Specification D3350 and Test Methods D3895, D4565, D5483, D6186, and E1858) where the time to the oxidation reaction under isothermal test conditions is measured. The OIT test method measures the presence of antioxidant packages and is a relative measurement of a material’s resistance to oxidation.1.1 This test method describes the measurement of reaction induction time (RIT) of chemical materials that undergo exothermic reactions with an induction period. The techniques and apparatus described may be used for solids, liquids, or slurries of chemical substances. The temperature range covered by this test method is typically from ambient to 400 °C. This range may be extended depending upon the apparatus used.1.2 The RIT is a relative index value, not an absolute thermodynamic property. As an index value, the RIT value may change depending upon experimental conditions. A comparison of RIT values may be made only for materials tested under similar conditions of apparatus, specimen size, and so forth. Furthermore, the RIT value may not predict behavior of large quantities of material.1.3 The RIT shall not be used by itself to establish a safe operating temperature. It may be used in conjunction with other test methods (for example, Test Methods E487 and E537, and Guide E1981) as part of a hazard analysis of a particular operation.1.4 This test method may be used for RIT values greater than 15 min (as relative imprecision increases at shorter periods).1.5 This test method is used to study catalytic, autocatalytic, and accelerating reactions. These reactions depend upon time as well as temperature. Such reactions are often studied by fixing one experimental parameter (that is, time or temperature) and then measuring the other parameter (that is, temperature or time). This test method measures time to reaction onset detection under isothermal conditions. It is related to Test Method E487 that measures detected reaction onset temperature under constant time conditions1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this test method.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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This guide is intended for use in any laboratory utilizing PCR or RT-PCR to amplify and detect nucleic acid sequences of mycobacteria from a biological preparation and to identify the species of origin.The criteria used for the identification and evaluation of the amplification reactions should be administered by an individual trained in the use of molecular biological and microbiological techniques associated with PCR and MTB.1.1 This guide covers basic considerations, criteria, principles and recommendations that should be helpful when developing, utilizing, or assessing PCR-specific protocols for the amplification and detection or identification of mycobacterial nucleic acids. This guide is not a specific protocol for the detection of specific mycobacteria. It is intended to provide information that will assist the user in obtaining high quality and reliable data. The guide is closely related to and should be used concurrently with the general PCR Guide E 1873.1.2 This guide has been developed for use in any molecular biology or biotechnology laboratory. It may be useful for the detection of mycobacteria in clinical, diagnostic laboratories.1.3 This guide does not cover details of the various methods such as gel electrophoresis that can be utilized to help identify PCR-amplified mycobacterial nucleic acid sequences, and it does not cover details of instrument calibration.1.4 This guide does not cover specific variations of the basic PCR or RT-PCR technology (for example, quantitative PCR, multiplex PCR and in situ PCR), and it does not cover details of instrument calibration.1.5 Warning-Laboratory work involving certain clinical specimens and microorganisms can be hazardous to personnel. Precaution: Biosafety Level 2 facilities are recommended for potentially hazardous work, and Biosafety Level 3 facilities are required for propagating and manipulating Mycobacteria tuberculosis cultures (). Safety guidelines should be adhered to according to NCCLS M29-T2, I17-P and other recommendations ().

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5.1 Both NO2 and NO play an important role in photochemical-smog-forming reactions. In sufficient concentrations NO2 is deleterious to health, agriculture, materials, and visibility.5.2 In combustion processes, significant amounts of NO may be produced by combination of atmospheric nitrogen and oxygen; at ambient temperatures, NO can be converted to NO2 by oxygen and other atmospheric oxidants. Nitrogen dioxide also may be generated from processes involving nitric acid, nitrates, the use of explosives, and welding.1.1 This test method covers the manual determination of the combined nitrogen dioxide (NO2) and nitric oxide (NO) content, total NOx; in the atmosphere in the range from 4 to 10 000 μg/m3 (0.002 to 5 ppm (v)).1.2 The maximum sampling period is 60 min at a flow rate of 0.4 L/min.1.3 The values stated in SI units are to be regarded as 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, 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 Although Test Method D4017 is widely used for the determination of water in paints and related materials, this method may overcome some of the variability found in the Karl Fischer method.4.2 Control of water content is often important in controlling the performance of paints, and it is critical in determining volatile organic compound (VOC) content when VOC content is measured by difference from total volatile matter and water content as required in certain federal and state regulations.1.1 This test method describes the determination of the total water content of paints using a calcium hydride reaction test kit, or water content between 2 and 85 % water.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, 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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4.1 This test method can be extended to use any material that has the necessary nuclear and activation properties that suit the experimenter's particular situation. No attempt has been made to fully describe the myriad problems of counting techniques, neutron-fluence depression, and thick-foil self-shielding. It is assumed that the experimenter will refer to existing literature on these subjects. This test method does offer a referee technique (the standard gold foil) to aid the experimenter when they are in doubt of their ability to perform the radiometric technique with sufficient accuracy.4.2 The standard comparison technique uses a set of foils that are as nearly identical as possible in shape and mass. The foils are fabricated from any material that activates by an (n, γ) reaction, preferably having a cross section approximately inversely proportional to neutron speed in the thermal energy range. Some of the foils are irradiated in a known neutron field (at NIST) or other standards laboratory). The foils are counted in a fixed geometry on a stable radiation-detecting instrument. The neutron-induced reaction rate of the foils is computed from the counting data, and the ratio of the known neutron fluence rate to the computed reaction rate is determined. For any given foil, neutron energy spectrum, and counting set-up, this ratio is a constant. Other foils from the identical set can now be exposed to an unknown neutron field. The magnitude of the fluence rate in the unknown field can be obtained by comparing the reaction rates as determined from the counting data from the unknown and reference field, with proper corrections to account for spectral differences between the two fields (see Section 5). One important feature of this technique is that it eliminates the need for knowing the detector efficiency.4.3 This test method follows the Stoughton and Halperin convention for reporting thermal neutron fluence. Other conventions are the Wescott convention (followed in Test Method E481) and the Hogdahl convention. Practice E261 explains the three conventions and gives conversion formulae relating values determined by the different conventions. Reference (1)3 discusses the three thermal-neutron conventions in detail.1.1 The purpose of this test method is to define a general procedure for determining an unknown thermal-neutron fluence rate by neutron activation techniques. It is not practicable to describe completely a technique applicable to the large number of experimental situations that require the measurement of a thermal-neutron fluence rate. Therefore, this method is presented so that the user may adapt to their particular situation the fundamental procedures of the following techniques.1.1.1 Radiometric counting technique using pure cobalt, pure gold, pure indium, cobalt-aluminum, alloy, gold-aluminum alloy, or indium-aluminum alloy.1.1.2 Standard comparison technique using pure gold, or gold-aluminum alloy, and1.1.3 Secondary standard comparison techniques using pure indium, indium-aluminum alloy, pure dysprosium, or dysprosium-aluminum alloy.1.2 The techniques presented are limited to measurements at room temperatures. However, special problems when making thermal-neutron fluence rate measurements in high-temperature environments are discussed in 9.2. For those circumstances where the use of cadmium as a thermal shield is undesirable because of potential spectrum perturbations or of temperatures above the melting point of cadmium, the method described in Test Method E481 can be used in some cases. Alternatively, gadolinium filters may be used instead of cadmium. For high temperature applications in which aluminum alloys are unsuitable, other alloys such as cobalt-nickel or cobalt-vanadium have been used.1.3 This test method may be used to determine the equivalent 2200 m/s fluence rate. The accurate determination of the actual thermal neutron fluence rate requires knowledge of the neutron temperature, and determination of the neutron temperature is not within the scope of the standard.1.4 The techniques presented are suitable only for neutron fields having a significant thermal neutron component, in which moderating materials are present, and for which the average scattering cross section is large compared to the average absorption cross section in the thermal neutron energy range.1.5 Table 1 indicates the useful neutron-fluence ranges for each detector material.TABLE 1 Useful Neutron Fluence Ranges of Foil MaterialFoil Material Form ≈ Useful Range (neutrons/cm 2)Indium pure or alloyed with aluminum 103 to 1012Gold pure or alloyed with aluminum 107 to 1014Dysprosium pure or alloyed with aluminum 103 to 1010Cobalt pure or alloyed with aluminum 1014 to 10201.6 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 Refer to Guides E720 and E844 for the selection, irradiation, and quality control of neutron dosimeters. 5.2 Refer to Practice E261 for a general discussion of the determination of fast-neutron fluence and fluence rate with threshold detectors. 5.3 The activation reaction produces 32P, which decays by the emission of a single beta particle in 100 % of the decays, and which emits no gamma rays. The half life of 32P is 14.284 (36)3 days (1) 4 and the maximum beta energy is 1710.66 (21) keV (1). 5.4 Elemental sulfur is readily available in pure form and any trace contaminants present do not produce significant amounts of radioactivity. Natural sulfur, however, is composed of 32S (94.99 % (26)), 34S (4.25 % (24)) (2), and trace amounts of other sulfur isotopes. The presence of these other isotopes leads to several competing reactions that can interfere with the counting of the 1710-keV beta particle. This interference can usually be eliminated by the use of appropriate techniques, as discussed in Section 8. 1.1 This test method describes procedures for measuring reaction rates and fast-neutron fluences by the activation reaction 32S(n,p)32P. 1.2 This activation reaction is useful for measuring neutrons with energies above approximately 3 MeV. 1.3 With suitable techniques, fission-neutron fluences from about 5 × 108 to 1016 n/cm 2 can be measured. 1.4 Detailed procedures for other fast-neutron detectors are described in Practice E261. 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 Refer to Guide E844 for the selection, irradiation, and quality control of neutron dosimeters.5.2 Refer to Practice E261 for a general discussion of the determination of fast-neutron fluence rate with threshold detectors.5.3 Pure aluminum in the form of foil or wire is readily available and easily handled. 27Al has an abundance of 100 % (1).35.4 24Na has a half-life of 14.958 (2)4 h (2) and emits gamma rays with energies of 1.368630 (5) and 2.754049 (13) MeV (2).5.5 Fig. 1 shows a plot of the International Reactor Dosimetry and Fusion File (IRDFF-II) cross section (3, 4) versus neutron energy for the fast-neutron reaction 27Al(n,α) 24Na (3) along with a comparison to the current experimental database (5, 6). While the RRDF-2008 and IRDFF-1.05 cross sections extend from threshold up to 60 MeV, due to considerations of the available validation data, the energy region over which this standard recommends use of this cross section for reactor dosimetry applications only extends from threshold at ~4.25 MeV up to 20 MeV. This figure is for illustrative purposes and is used to indicate the range of response of the 27Al(n,α) reaction. Refer to Guide E1018 for recommended sources for the tabulated dosimetry cross sections.FIG. 1 27Al(n,α)24Na Cross Section, from IRDFF-II Library, with EXFOR Experimental Data5.6 Two competing activities, 28Al (2.25 (2) minute half-life) and 27Mg (9.458 (12) minute half-life), are formed in the reactions 27Al(n,γ)28Al and 27Al(n,p)27Mg, respectively, but these can be eliminated by waiting 2 h before counting.1.1 This test method covers procedures measuring reaction rates by the activation reaction 27Al(n,α)24Na.1.2 This activation reaction is useful for measuring neutrons with energies above approximately 6.5 MeV and for irradiation times up to about two days (for longer irradiations, or when there are significant variations in reactor power during the irradiation, see Practice E261).1.3 With suitable techniques, fission-neutron fluence rates above 106 cm−2·s−1 can be determined.1.4 Detailed procedures for other fast neutron detectors are referenced in Practice E261.1.5 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 Refer to Guide E844 for guidance on the selection, irradiation, and quality control of neutron dosimeters. 5.2 Refer to Practice E261 for a general discussion of the determination of fast-neutron fluence rate with threshold detectors. 5.3 Pure iron in the form of foil or wire is readily available and easily handled. 5.4 Fig. 1 shows a plot of cross section as a function of neutron energy for the fast-neutron reaction 54Fe(n,p)54Mn (1).3 This figure is for illustrative purposes only to indicate the range of response of the 54Fe(n,p)54Mn reaction. Refer to Guide E1018 for recommended tabulated dosimetry cross sections. FIG. 1 54Fe(n,p)54Mn Cross Section 5.5 54Mn has a half-life of 312.19 (3) days4 (2) and emits a gamma ray with an energy of 834.855 (3) keV (2). 5.6 Interfering activities generated by neutron activation arising from thermal or fast neutron interactions are 2.57878 (46)-h 56Mn, 44.494 (12) days 59Fe, and 5.2711 (8) years 60Co (2,3). (Consult the latest version of Ref (2) for more precise values currently accepted for the half-lives.) Interference from 56Mn can be eliminated by waiting 48 h before counting. Although chemical separation of 54Mn from the irradiated iron is the most effective method for eliminating 59Fe and 60Co, direct counting of iron for 54Mn is possible using high-resolution detector systems or unfolding or stripping techniques, especially if the dosimeter was covered with cadmium or boron during irradiation. Altering the isotopic composition of the iron dosimeter is another useful technique for eliminating interference from extraneous activities when direct sample counting is to be employed. 5.7 The vapor pressures of manganese and iron are such that manganese diffusion losses from iron can become significant at temperatures above about 700°C. Therefore, precautions must be taken to avoid the diffusion loss of 54Mn from iron dosimeters at high temperature. Encapsulating the iron dosimeter in quartz or vanadium will contain the manganese at temperatures up to about 900°C. 5.8 Sections 6, 7 and 8 that follow were specifically written to describe the method of chemical separation and subsequent counting of the 54Mn activity. When one elects to count the iron dosimeters directly, those portions of Sections 6, 7 and 8 that pertain to radiochemical separation should be disregarded. Note 1: The following portions of this test method apply also to direct sample-counting methods: 6.1 – 6.3, 7.4, 7.9, 7.10, 8.1 – 8.5, 8.18, 8.19, and 9 – 12. 1.1 This test method describes procedures for measuring reaction rates by the activation reaction 54Fe(n,p)54Mn. 1.2 This activation reaction is useful for measuring neutrons with energies above approximately 2.2 MeV and for irradiation times up to about three years, provided that the analysis methods described in Practice E261 are followed. If dosimeters are analyzed after irradiation periods longer than three years, the information inferred about the fluence during irradiation periods more than three years before the end of the irradiation should not be relied upon without supporting data from dosimeters withdrawn earlier. 1.3 With suitable techniques, fission-neutron fluence rates above 108 cm−2·s−1 can be determined. However, in the presence of a high thermal-neutron fluence rate (for example, >2 × 1014 cm−2·s −1) 54Mn depletion should be investigated. 1.4 Detailed procedures describing the use of other fast-neutron detectors are referenced in Practice E261. 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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5.1 Refer to Guide E844 for the selection, irradiation, and quality control of neutron dosimeters. 5.2 Refer to Practice E261 for a general discussion of the determination of fast-neutron fluence rate with threshold detectors. 5.3 Pure nickel in the form of foil or wire is readily available, and easily handled. 5.4 58Co has a half-life of 70.85 (3) days (Refs (1) and (2))3 and emits a gamma ray with an energy of 810.7602 (20) keV (Refs (2) and (3)). 5.5 Competing activities 65Ni(2.5172 h) and 57Ni(35.9 (3) h (Ref (2)) are formed by the reactions 64Ni(n,γ) 65Ni, and 58Ni(n,2n)57Ni, respectively. 5.6 A second 9.04 h isomer, 58mCo, is formed that decays to 70.85-day 58Co. Loss of 58Co and 58mCo by thermal-neutron burnout will occur in environments (Refs (4) and (5) having thermal fluence rates of 3 × 1012 cm−2·s −1 and above. Burnout correction factors, R, are plotted as a function of time for several thermal fluxes in Fig. 1. Tabulated values for a continuous irradiation time are provided in Hogg, et al. (Ref (5)) 5.7 Fig. 2 shows a plot of cross section (Ref (6)) versus energy for the fast-neutron reaction 58Ni(n,p) 58Co. This figure is for illustrative purposes only to indicate the range of response of the 58Ni(n,p) reaction. Refer to Guide E1018 for descriptions of recommended tabulated dosimetry cross sections. FIG. 2 58Ni(n,p)58Co Cross Section Note 1: The data is taken from the Evaluated Nuclear Data File, ENDF/B-VI, rather than the later ENDF/B-VII. This is in accordance with E1018, section 6.1, since the later ENDF/B-VII data files do not include covariance information. For more details see Section H of Ref (7). 1.1 This test method covers procedures for measuring reaction rates by the activation reaction 58Ni(n,p)58Co. FIG. 1 R Correction Values as a Function of Irradiation Time and Neutron Flux Note 1: The burnup corrections were computed using effective burn-up cross sections of 1650 b for  58Co(n,γ) and 1.4E5 b for  58mCo(n,γ). 1.2 This activation reaction is useful for measuring neutrons with energies above approximately 2.1 MeV and for irradiation times up to about 200 days in the absence of high thermal neutron fluence rates, provided that the analysis methods described in Practice E261 are followed. If dosimeters are analyzed after irradiation periods longer than 200 days, the information inferred about the fluence during irradiation periods more than 200 days before the end of the irradiation should not be relied upon without supporting data from dosimeters withdrawn earlier. 1.3 With suitable techniques fission-neutron fluence rates densities above 107 cm−2·s −1 can be determined. 1.4 Detailed procedures for other fast-neutron detectors are referenced in Practice E261. 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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5.1 Refer to Guide E844 for the selection, irradiation, and quality control of neutron dosimeters. 5.2 Refer to Practice E261 for a general discussion of the measurement of fast neutron fluence rate with threshold detectors. The general shape of the 63Cu(n,α) 60Co cross section is also shown in Fig. 1 (3, 4, 5) along with a comparison to the current experimental database (6). This figure is for illustrative purposes only to indicate the range of the response of the 63Cu(n,α)60Co reaction. Refer to Guide E1018 for descriptions of recommended tabulated dosimetry cross sections. FIG. 1 63Cu(n,α)60Co Cross Section with EXFOR Experimental Data Note 1: The cross section appropriate for use under this standard is from the IRDFF-II library (5) which, up to an incident neutron energy of 20 MeV, is drawn from the RRDF-2002 library (3) and is identical to the adopted cross section in the IRDF-2002 library (4). See Guide E1018. 5.3 The major advantages of copper for measuring fast-neutron fluence rate are that it has good strength, is easily fabricated, has excellent corrosion resistance, has a melting temperature of 1083°C, and can be obtained in high purity. The half-life of   60 Co is long and its decay scheme is simple and well known. 5.4 The disadvantages of copper for measuring fast neutron fluence rate are the high reaction apparent threshold of 4.5 MeV, the possible interference from cobalt impurity (>1 μg/g), the reported possible thermal component of the (n,α) reaction, and the possibly significant cross sections for thermal neutrons for   63Cu and 60Co [that is, 4.50(2) and 2.0(2) barns, respectively], (7), which will require burnout corrections at high fluences. 1.1 This test method covers procedures for measuring reaction rates by the activation reaction 63Cu(n,α) 60Co. The cross section for 60Co produced in this reaction increases rapidly with neutrons having energies greater than about 4.5 MeV. 60Co decays with a half-life of 5.2711(8)2 years (1)3,4 and emits two gamma rays having energies of 1.173228(3) and 1.332492(4) MeV (1). The isotopic content of natural copper is 69.174(20) % 63Cu and 30.826(20) % 65Cu (2). The neutron reaction, 63Cu(n,γ)64Cu, produces a radioactive product that emits gamma rays [1.34577(6) MeV (E1005)] which might interfere with the counting of the 60Co gamma rays. 1.2 With suitable techniques, fission-neutron fluence rates above 109 cm−2·s−1 can be determined. The 63Cu(n,α)60Co reaction can be used to determine fast-neutron fluences for irradiation times up to about 15 years, provided that the analysis methods described in Practice E261 are followed. If dosimeters are analyzed after irradiation periods longer than 15 years, the information inferred about the fluence during irradiation periods more than 15 years before the end of the irradiation should not be relied upon without supporting data from dosimeters withdrawn earlier. 1.3 Detailed procedures for other fast-neutron detectors are referenced in Practice E261. 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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5.1 This guide provides a protocol for detecting, characterizing, and quantifying nucleic acids (that is, DNA) of living and recently dead microorganisms in fuels and fuel-associated waters by means of a culture independent qPCR procedure. Microbial contamination is inferred when elevated DNA levels are detected in comparison to the expected background DNA level of a clean fuel and fuel system.5.2 A sequence of protocol steps is required for successful qPCR testing.5.2.1 Quantitative detection of microorganisms depends on the DNA-extraction protocol and selection of appropriate oligonucleotide primers.5.2.2 The preferred DNA extraction protocol depends on the type of microorganism present in the sample and potential impurities that could interfere with the subsequent qPCR reaction.5.2.3 Primers vary in their specificity. Some 16S and 18S RNA gene regions present in the DNA of prokaryotic and eukaryotic microorganisms appear to have been conserved throughout evolution and thus provide a reliable and repeatable target for gene amplification and detection. Amplicons targeting these conserved nucleotide sequences are useful for quantifying total population densities. Other target DNA regions are specific to a metabolic class (for example, sulfate reducing bacteria) or individual taxon (for example, the bacterial species Pseudomonas aeruginosa). Primers targeting these unique nucleotide sequences are useful for detecting and quantifying specific microbes or groups of microbes known to be associated with biodeterioration.5.3 Just as the quantification of microorganisms using microbial growth media employs standardized formulations of growth conditions enabling the meaningful comparison of data from different laboratories (Practice D6974), this guide seeks to provide standardization to detect, characterize, and quantify nucleic acids associated with living and recently dead microorganisms in fuel-associated samples using qPCR.NOTE 3: Many primers, and primer and probe combinations that are not covered in this guide may be used to perform qPCR. This guide does not attempt to cover all of the possible qPCR assays and does not suggest nor imply that the qPCR assays (that is, combinations of primers and probes, and reaction conditions) discussed here are better suited for qPCR than other qPCR assays not presented here. Additional, primers, primers and probes combination, and qPCR assay conditions may be added in the future to this guide as they become available to the ASTM scientific community. Guide D6469 reviews the types of damage that uncontrolled microbial growth in fuels and fuel systems can cause.5.4 Culture-based microbiological tests depend on the ability of microbes to proliferate in liquid, solid or semisolid nutrient media, in order for microbes in a sample to be detected.5.5 There is general consensus among microbiologists that only a fraction of the microbes believed to be present in the environment have been cultured successfully.5.6 Since the mid-1990s, genetic test methods that do not rely on cultivation have been increasingly favored for the detection and quantification of microorganisms in environmental samples.5.7 qPCR is a quantitative, culture-independent method that is currently used in the medical, food, and cosmetic industries for the detection and quantification of microorganisms.5.8 Since the early 2000s, qPCR methodology has evolved and is now frequently used to quantify microorganisms in fuel-associated samples, but there is currently no standardized methodology for employing qPCR for this application (1-6).3 The purpose of this guide is to provide guidance and standardization for genetic testing of samples using qPCR to quantify total microbial populations present in fuel-associated samples.5.9 Although this guide focuses on describing recommended protocols for the quantification of total microorganisms present in fuel-associated samples using qPCR, the procedures described here can also be applied to the standardization of qPCR assays for other genetic targets and environmental matrices.5.10 Genetic techniques have great flexibility so that it is possible to design a nearly infinite number of methods to detect and quantify each and every gene. Because of this flexibility of genetic techniques, it is important to provide a standard protocol for qPCR so that data generated by different laboratories can be compared.5.11 This guide provides recommendations for primers sequences and experimental methodology for qPCR assays for the quantification of total microorganisms present in fuel-associated samples.1.1 This guide covers procedures for using quantitative polymerase chain reaction (qPCR), a genomic tool, to detect, characterize and quantify nucleic acids associated with microbial DNA present in liquid fuels and fuel-associated water samples.1.1.1 Water samples that may be used in testing include, but are not limited to, water associated with crude oil or liquid fuels in storage tanks, fuel tanks, or pipelines.1.1.2 While the intent of this guide is to focus on the analysis of fuel-associated samples, the procedures described here are also relevant to the analysis of water used in hydrotesting of pipes and equipment, water injected into geological formations to maintain pressure and/or facilitate the recovery of hydrocarbons in oil and gas recovery, water co-produced during the production of oil and gas, water in fire protection sprinkler systems, potable water, industrial process water, and wastewater.1.1.3 To test a fuel sample, the live and recently dead microorganisms must be separated from the fuel phase which can include any DNA fragments by using one of various methods such as filtration or any other microbial capturing methods.1.1.4 Some of the protocol steps are universally required and are indicated by the use of the word must. Other protocol steps are testing-objective dependent. At those process steps, options are offered and the basis for choosing among them are explained.1.2 The guide describes the application of quantitative polymerase chain reaction (qPCR) technology to determine total bioburden or total microbial population present in fuel-associated samples using universal primers that allow for the quantification of 16S and 18S ribosomal RNA genes that are present in all prokaryotes (that is, bacteria and archaea) and eucaryotes (that is, mold and yeast collectively termed fungi), respectively.1.3 This guide describes laboratory protocols. As described in Practice D7464, the qualitative and quantitative relationship between the laboratory results and actual microbial communities in the systems from which samples are collected is affected by the time delay and handling conditions between the time of sampling and time that testing is initiated.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard with the exception of the concept unit of gene copies/mL (that is, 16S or 18S gene copies/mL) to indicate the starting concentration of microbial DNA for the intended microbial targets (that is, bacteria, archaea, fungi).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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3.1 General: 3.1.1 All testing shall define fender performance under velocities that decrease linearly or that are proportional to the square root of percent of remaining rated energy.3.1.2 Rated performance data (RPD) and manufacturers' published performance curves or tables, or both, shall be based on: (1) initial deflection (berthing) velocity of 0.15 m/s and decreasing to no more than 0.005 m/s at test end, (2) testing of fully broken-in fenders (break-in testing is not required for pneumatic fenders), (3) testing of fenders stabilized at 23 ± 5°C (excluding pneumatic fenders; see 6.3), (4) testing of fenders at 0° angle of approach, and (5) deflection (berthing) frequency of not less than 1 h (use a minimum 5-min deflection frequency for pneumatic fenders.).3.1.3 Catalogues shall also include nominal performance tolerances as well as data and methodology to adjust performance curves or tables or both for application parameters different from RPD conditions. Adjustment factors shall be provided for the following variables: (1) other initial velocities: 0.05, 0.10, 0.20, 0.25, and 0.30 m/s; (2) other temperatures: +50, +40, +30, +10, 0, −10, −20, −30; and (3) other contact angles: 3, 5, 8, 10, 15°. In addition, RPD shall contain a cautionary statement that published data do not necessarily apply to constant-load and cyclic-loading conditions. In such cases, designers are to contact fender manufacturers for design assistance.3.1.4 Adjustment factors for velocity and temperature shall be provided for every catalogue compound or other energy absorbing material offered by each manufacturer.3.2 Fender Testing—Performance testing to establish RPD must use either one of two methods:3.2.1 Method A—Deflection of full-size fenders at velocities inversely proportional to the percent of rated deflection or directly proportional to the square root of percent of remaining rated energy. Test parameters shall be as defined for published RPD. RPD tests shall start at 0.15 m/s. Tests to establish adjustment factors for initial berthing velocities other than 0.15 m/s shall start at those other initial velocities.3.2.2 Method B—Deflection of full size fenders at constant velocity with performance adjusted by velocity factors developed from model tests. Velocity factors shall be the ratio of performance test results of models under the following conditions: (1) a constant strain rate similar to the strain rate of the full-size fender at its test speed, and (2) decreasing speed deflection with initial strain rate similar to that of the full-size fender under RPD deflection conditions.3.2.3 The RPD for pneumatic fenders shall be determined using either Method A or Method B with miniature-size fenders; in which case, the compression performance of air shall be directly extrapolated from the test data of reduced scale models.1.1 This test method covers the recommended procedures for quantitative testing, reporting, and verifying the energy absorption and reaction force of marine fenders. Marine fenders are available in a variety of basic types with several variations of each type and multiple sizes and stiffnesses for each variation. Depending on the particular design, marine fenders may also include integral components of steel, composites, plastics, or other materials. All variations shall be performance tested and reported according to this test method.1.2 There are three performance variables: berthing energy, reaction, and deflection. There are two methods used to develop rated performance data (RPD) and published performance curves for the three performance variables.1.3 The primary focus is on fenders used in berthside and ship-to-ship applications for marine vessels. This testing protocol does not address small fendering “bumpers” used in pleasure boat marinas, mounted to hulls of work boats, or used in similar applications; it does not include durability testing. Its primary purpose is to ensure that engineering data reported in manufacturers' catalogues are based upon common testing methods.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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