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5.1 Solar reflectance and thermal emittance are important factors affecting surface and near-surface ambient air temperature. Surfaces with low solar reflectance, absorb a high fraction of the incoming solar energy. A fraction of this absorbed energy is conducted into ground and buildings, a fraction is convected to air (leading to higher air temperatures), and a fraction is radiated to the sky. For equivalent conditions, the lower the emissivity of a surface the higher its steady-state temperature. Surfaces with low emissivity cannot effectively radiate to the sky and, therefore, get hot. Determination of solar reflectance and thermal emittance, and subsequent calculation of the relative temperature of the surfaces with respect to black and white reference temperature (defined as Solar Reflectance Index, SRI), may help designers and consumers to choose the proper materials to make their buildings and communities energy efficient. The method described here gives the SRI of surfaces based on measured solar reflectances and thermal emissivities of the surfaces.1.1 This practice covers the calculation of the Solar Reflectance Index (SRI) of horizontal and low-sloped opaque surfaces at standard conditions. The method is intended to calculate SRI for surfaces with emissivity greater than 0.1.1.2 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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1.1 These procedures cover the chemical analysis by the lime ignition method of treating solutions containing pentachlorophenol and of wood treated with pentachlorophenol. The method is suitable for the determination of up to 0.05 g of pentachlorophenol in treating solutions (Section ), up to 0.05 g of pentachlorophenol in wood volumes up to 0.25 in.3 (Section 11), and up to 0.25 g of pentachlorophenol in wood volumes up to 2.0 in.3 (Section ).1.2 This test method is not applicable to samples containing halogens other than chlorine unless appropriate correction can be made. Total halogen (excluding fluorine) is calculated as its pentachlorophenol equivalent of chloride.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

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4.1 Test Methods E119 and E1529, and other standard fire resistance test methods specify that throughout exposures to fire and the hose stream, a constant superimposed axial load be applied to a load-bearing test specimen to simulate a maximum load condition. These test methods specify that this superimposed load shall be as nearly as practicable the maximum allowable axial design load allowed by design under nationally recognized structural design criteria. For this practice, the nationally recognized structural design criteria is the National Design Specification (NDS) for Wood Construction4.1.1 Alternatively, the standard fire resistance test methods shall be conducted by applying an axial load that is less than the maximum allowable axial design load as addressed by the NDS and this practice, but these tests shall be identified in the test report as being conducted under restricted load conditions.4.1.2 The superimposed axial load, as well as the superimposed axial load as a percentage of the maximum allowable axial design load for the stud and as a percentage of the maximum allowable design load for the plate, shall be calculated using the Allowable Stress Design (ASD) method in the NDS and this practice shall be included in the test report.NOTE 1: The NDS should be used to ensure calculation of the superimposed load is in compliance with all applicable provisions of that document. Appendix X1 describes how to calculate the superimposed load in accordance with the NDS.4.2 This practice describes procedures for calculating the superimposed axial load to be applied in standard fire resistance tests of wood-frame wall assemblies.4.3 Statements in either the fire resistance test method standard or the nationally recognized structural design standard supersede any procedures described by this practice.1.1 This practice covers procedures for calculating the superimposed axial load required to be applied to load-bearing wood-frame walls throughout standard fire-resistance and fire and hose-stream tests.1.2 The calculations determine the maximum load allowed by design for wood-frame wall assemblies under nationally recognized structural design criteria.1.3 This practice is only applicable to those wood-frame assemblies for which the nationally recognized structural design criteria are contained in the National Design Specification for Wood Construction (NDS).21.4 The system of units to be used is that of the nationally recognized structural design criteria. For the NDS, the units are inch-pound.1.5 The text of this standard references notes and footnotes which provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the 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 This practice should be used only to compare specimens of the same material and same general appearance. For example, a series of specimens to be compared should have generally similar gloss, texture, and (if not opaque) thickness, and translucency.5.2 For yellowness measurement, this practice is limited to specimens having dominant wavelength in the range 570 to 580 nm, or Munsell hue approximately 2.5GY to 2.5Y. For whiteness measurement, this practice is limited to specimens having Munsell value greater than 8.3 (CIE Y greater than 65) and Munsell chroma no greater than 0.5 for B hues, 0.8 for Y hues, and 0.3 for all other hues (see 3.3.1).5.3 The combination of measurement and calculation leading to indices of yellowness or whiteness is a psychophysical process, that is, the procedures specified are designed to provide numbers correlating with visual estimates made under specified typical observing conditions. Because visual observing conditions can vary widely, users should compare calculated indices with visual estimates to ensure applicability. Some standards addressing the visual estimation of color and color difference are Practices D1535, D1729, E1360, and E1541, and Guide E1499.5.4 This practice does not cover the preparation of specimens, a procedure that may affect significantly the quantities measured. In general, specimens should be prepared and presented for measurement in the manner that is standard for the test being performed. Select enough specimens or specimen areas to provide an average result that is representative of each sample to be tested. See Practice E1345.1.1 This practice provides numbers that correlate with visual ratings of yellowness or whiteness of white and near-white or colorless object-color specimens, viewed in daylight by an observer with normal color vision. White textiles, paints, and plastics are a few of the materials that can be described by the indices of yellowness or whiteness calculated by this practice.1.2 For a complete analysis of object colors, by a specified observer and under a specified illuminant, use of three parameters is required. For near-white specimens, however, it is often useful to calculate single-number scales of yellowness or whiteness. This practice provides recommended equations for such scales and discusses their derivations and uses, and limits to their applicability (see also Ref (1)2).1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, 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 Physical constants of paints and coatings are required in all aspects of their formulation, manufacture and use. This practice demonstrates standard methods agreed upon for calculating formulation values for some of these physical constants. The calculations are the same for either metric or inch/pound units.4.2 These formula values may not be used to replace measured values required by government regulations unless specifically stated in the governing documents.4.3 Some regulations allow compliance determination using formulation data instead of analytical data. This formulation data may not yield the same results as the required analytical method, which could be performed on a sample from any production batch of the coating. In these cases, the user may wish to compare formulation data to analytical data and develop a factor that adjusts for variability of raw materials, variability of production batches, cure volatiles, and variability of the analytical methods.1.1 This practice covers procedures commonly used in the paint industry to formulate paints and coating materials. It describes procedures for calculating formulation values for weight solids, volume solids, solvent content, volatile organic compound (VOC) content, hazardous air pollutant (HAP) content, and density of liquid paints and coatings. These values are calculated from basic formulation data. These calculations may be related to either as-supplied (unreduced) or as-applied (reduced) coating materials, including multicomponent types.1.2 These calculated, formulation-based values may or may not be acceptable for VOC regulatory purposes, depending on the specific wording of the applicable regulation. Some regulations require analysis of the coating. Some rules allow the use of formulation data, however, some adjustments may be needed to the values calculated in this practice before they are used for regulatory purposes (see 4.3).1.3 For purposes of this practice, it is assumed that volatile components evaporate and the materials that remain are identified as coating solids. For example, solvents are normally used to adjust viscosity for application and appearance of the coating. Other liquid materials, such as plasticizers, reactive diluents, etc., that are expected to be retained in the dried film to affect the final physical properties should be classified as part of the coating solids. Standards such as Test Methods D2369, D4758, D5403, and Guide D2832 may be used to determine volatile or nonvolatile content of specific components. For purposes of this practice it is assumed that the blended formulation behaves as an ideal solution with no volume change on mixing (see 6.2).1.4 Volatile by-products of cross-linking reactions (cure volatiles) are not considered in these calculations since the object of this practice is to define paint physical constants based on formulation information. Variations in raw materials, variations in the production processes, test methods, and test method accuracy are not taken into account in these calculations.1.5 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. However, they may be readily converted into SI units, if required by the user (for example, see Note 4).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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6.1 Sensory thresholds are used to determine the potential of substances at low concentrations to impart odor, taste, skinfeel, etc. to some form of matter.6.2 Thresholds are used, for example, in setting limits in air pollution, in noise abatement, in water treatment, and in food systems.6.3 Thresholds are used to characterize and compare the sensitivity of individuals or groups to given stimuli, for example, in medicine, ethnic studies, and the study of animal species.1.1 The definitions and procedures of this practice apply to the calculation of individual thresholds for any stimulus in any medium, from data sets of intermediate size, that is, consisting of more than 20 to 40 3-AFC presentations per individual. A group threshold may be calculated using 5 to 15 individual thresholds.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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ASTM E2586-19e1 Standard Practice for Calculating and Using Basic Statistics Active 发布日期 :  1970-01-01 实施日期 : 

4.1 This practice provides approaches for characterizing a sample of n observations that arrive in the form of a data set. Large data sets from organizations, businesses, and governmental agencies exist in the form of records and other empirical observations. Research institutions and laboratories at universities, government agencies, and the private sector also generate considerable amounts of empirical data.4.1.1 A data set containing a single variable usually consists of a column of numbers. Each row is a separate observation or instance of measurement of the variable. The numbers themselves are the result of applying the measurement process to the variable being studied or observed. We may refer to each observation of a variable as an item in the data set. In many situations, there may be several variables defined for study.4.1.2 The sample is selected from a larger set called the population. The population can be a finite set of items, a very large or essentially unlimited set of items, or a process. In a process, the items originate over time and the population is dynamic, continuing to emerge and possibly change over time. Sample data serve as representatives of the population from which the sample originates. It is the population that is of primary interest in any particular study.4.2 The data (measurements and observations) may be of the variable type or the simple attribute type. In the case of attributes, the data may be either binary trials or a count of a defined event over some interval (time, space, volume, weight, or area). Binary trials consist of a sequence of 0s and 1s in which a “1” indicates that the inspected item exhibited the attribute being studied and a “0” indicates the item did not exhibit the attribute. Each inspection item is assigned either a “0” or a “1.” Such data are often governed by the binomial distribution. For a count of events over some interval, the number of times the event is observed on the inspection interval is recorded for each of n inspection intervals. The Poisson distribution often governs counting events over an interval.4.3 For sample data to be used to draw conclusions about the population, the process of sampling and data collection must be considered, at least potentially, repeatable. Descriptive statistics are calculated using real sample data that will vary in repeating the sampling process. As such, a statistic is a random variable subject to variation in its own right. The sample statistic usually has a corresponding parameter in the population that is unknown (see Section 5). The point of using a statistic is to summarize the data set and estimate a corresponding population characteristic or parameter, or to test a hypothesis.4.4 Descriptive statistics consider numerical, tabular, and graphical methods for summarizing a set of data. The methods considered in this practice are used for summarizing the observations from a single variable. The descriptive statistics described in this practice are: mean, median, min, max, range, mid range, order statistic, quartile, empirical percentile, quantile, interquartile range, variance, standard deviation, Z-score, coefficient of variation, and skewness and kurtosis.4.5 Statistical inference is drawing conclusions about the population or its parameters. Methods for statistical inference described in this practice are: degrees of freedom, standard error, confidence intervals, prediction intervals, tolerance intervals, and statistical hypothesis tests.4.6 Tabular methods described in this practice are: frequency distribution, relative frequency distribution, cumulative frequency distribution, and cumulative relative frequency distribution.4.7 Graphical methods described in this practice are: histogram, ogive, boxplot, dotplot, normal probability plot, and q-q plot.4.8 While the methods described in this practice may be used to summarize any set of observations, the results obtained by using them may be of little value from the standpoint of interpretation unless the data quality is acceptable and satisfies certain requirements. To be useful for inductive generalization, any sample of observations that is treated as a single group for presentation purposes must represent a series of measurements, all made under essentially the same test conditions, on a material or product, all of which have been produced under essentially the same conditions. When these criteria are met, we are minimizing the danger of mixing two or more distinctly different sets of data.4.8.1 If a given collection of data consists of two or more samples collected under different test conditions or representing material produced under different conditions (that is, different populations), it should be considered as two or more separate subgroups of observations, each to be treated independently in a data analysis program. Merging of such subgroups, representing significantly different conditions, may lead to a presentation that will be of little practical value. Briefly, any sample of observations to which these methods are applied should be homogeneous or, in the case of a process, have originated from a process in a state of statistical control.4.9 The methods developed in Sections 6, 7, 8, and 9 apply to the sample data. There will be no misunderstanding when, for example, the term “mean” is indicated, that the meaning is sample mean, not population mean, unless indicated otherwise. It is understood that there is a data set containing n observations. The data set may be denoted as:4.9.1 There is no order of magnitude implied by the subscript notation unless subscripts are contained in parenthesis (see 6.7).AbstractThis practice covers methods and equations for computing and presenting basic statistics. This practice includes simple descriptive statistics for variable and attribute data, elementary methods of statistical inference, and tabular and graphical methods for variable data. Some interpretation and guidance for use is also included.This practice provides approaches for characterizing a sample of n observations that arrive in the form of a data set. Large data sets from organizations, businesses, and governmental agencies exist in the form of records and other empirical observations. Research institutions and laboratories at universities, government agencies, and the private sector also generate considerable amounts of empirical data.1.1 This practice covers methods and equations for computing and presenting basic statistics. This practice includes simple descriptive statistics for variable and attribute data, elementary methods of statistical inference, and tabular and graphical methods for variable data. Some interpretation and guidance for use is also included.1.2 The system of units for this practice is not specified. Dimensional quantities in the practice are presented only as illustrations of calculation methods. The examples are not binding on products or test methods treated.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 practice shall only be used on soils having infiltration rates ranging from 2.5 mm/h (field hydraulic conductivity of 6.9 × 10-7 m/s) to 15000 mm/h (field hydraulic conductivity of 4.0 × 10-3 m/s).5.2 This practice is useful for field measurement of the infiltration rate and calculation of field hydraulic conductivity of soils. It was initially developed for stormwater treatment applications, and has been used to design, verify the construction of, and perform annual testing on surface drainage applications such as rain gardens or storm water collection systems (1). Other suitable applications include evaluation of potential septic-tank disposal fields (ASTM D5879 and D5921), leaching and drainage efficiencies, irrigation requirements, erosion potential, forestry, agriculture, and water spreading and recharge, among other applications. This test is not intended for use in hydraulic barriers/seals such as landfill liners, nuclear waste repositories, or the core of a dam. This test is also not intended for use in soils that experience changes in volume during infiltration, such as collapsible or expansive soils.5.3 Field hydraulic conductivity can only be calculated when the hydraulic boundary conditions are known, such as hydraulic gradient and the extent of lateral flow of water, or these can be reliably estimated.NOTE 1: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.5.4 A mathematical analysis has been developed for this test that follows the Green-Ampt analysis that assumes a relationship between the volumetric water content and the depth of the wetting front, in that volumetric water content profile at the wetting front is represented by a sharp transition between the initial value in the ground and that of saturated soil, that is, the porosity (1), (2).5.5 Many factors affect the infiltration rate, for example the soil structure, soil layering, condition of the soil surface, degree of saturation of the soil, chemical and physical nature of the soil and of the applied liquid, head of the applied liquid, temperature of the liquid, and diameter and depth of embedment of rings. Thus, tests made at the same site are not likely to give identical results and the rate measured by the practice described in this standard is primarily for comparative use.1.1 This practice describes a procedure for field measurement of the infiltration rate of liquid (typically water) into soils using the modified Philip Dunne (MPD) infiltrometer. The data from the field measurement is then used to calculate the field hydraulic conductivity. Soils should be regarded as natural occurring fine or coarse-grained soils or processed materials or mixtures of natural soils and processed materials, or other porous materials, and which are basically insoluble and are in accordance with requirements of 5.1.1.2 This practice may be conducted at the ground surface or at given depths in pits, on bare soil or with vegetation in place, depending on the conditions for which infiltration rates are desired. However, this practice cannot be conducted where the test surface is at or below the groundwater table, a perched water table, or the capillary fringe.1.3 This practice is for soils within a range of infiltration rate range defined in 5.1, as long as an adequate seal can be made between the MPD Infiltrometer base and the soil being tested. In highly permeable soils, readings can be taken at shorter intervals, to ensure that enough data are collected to determine the infiltration rate.1.4 The field measurement is a falling head test that can be performed relatively quickly (30 to 60 minutes) in silty sand or clayey sand soils suitable for stormwater infiltration practices. It is suitable for testing several locations across a site, to characterize the spatial variability of the infiltration rate throughout the site.1.5 The field measurement can be used to measure the infiltration rate, which can be used to calculate the field hydraulic conductivity. The field hydraulic conductivity can be used as an index to compare the suitability of soils for use in the development of surface drainage applications (for example, rain gardens or stormwater fills).1.6 Units—The values stated in SI units are to be regarded as the standard. No other units of measurement are to be included in this standard.1.7 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.1.8 The procedures used to specify how data are collected/recorded or calculated in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analytical methods for engineering design.1.9 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.1.10 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 Fireclay steel-teeming nozzles and sleeves are classified by volume reheat change. Bloating of some refractories results in irregular reheat dimensions, which are difficult to measure. This practice determines the volume without depending upon physical linear measurements.3.2 Blast furnace checkers that have irregular cross-sections are classified by “creep properties.” This practice determines the average cross-sectional area.1.1 This practice covers the methods of calculating areas, volumes, and linear changes of irregularly shaped refractory specimens.1.2 The specimens must have a constant cross-sectional area over a length (L).1.3 The values stated in SI units are to be regarded as the standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, 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 The property retention index (PRI) determined by this practice is intended primarily to provide relative durability performance information on materials for design engineers. It is up to the user to ensure that appropriate sampling procedures are used for the selection of specimens to be exposed so that the PRI data obtained is actually representative of the material being evaluated.4.2 The PRI obtained depends on the material being tested, property being evaluated, and exposure condition used. A PRI obtained for one property will probably not be the same as the PRI for a different property of the same material, even if the same exposure test is used.4.3 Plastics exposed to a combination of environmental and thermal treatments may undergo a change in functional performance. Any laboratory-accelerated aging procedure, especially those that use only a single stress, may not realistically indicate the changes a plastic may undergo in actual use conditions. This practice provides a means for expressing the changes in properties as a function of time exposed in a wide variety of tests. The PRI data obtained is best used for comparing the performance of materials subjected to the same exposure test simultaneously.4.3.1 Both laboratory-accelerated and outdoor exposure testing can be highly variable, and the PRI data will be influenced by this variability. For example, PRI data from outdoor exposures can vary depending on the exposure location and the time of year when the exposure is conducted. Variability in laboratory-accelerated exposure tests can result in large differences in PRI data from two laboratories running supposedly identical tests. PRI data obtained from exposure to laboratory-accelerated tests cannot be used to predict the PRI for exposure to natural weathering or actual use conditions unless there is a sufficient amount of data from both types of exposure to allow valid statistical comparisons.4.4 A number of different exposure techniques can be used to provide information on the effects of environmental stresses such as light, heat, and water on plastics (see Practices D1435, D1499, D2565, D4329, D4364, and D4459; Test Method D4674; and ISO 877 and ISO 4892). When it is desirable to evaluate the effects of heat alone, exposures should be conducted in accordance with Practice D3045. When it is desirable to evaluate the effects of chemical exposures, the exposures should be conducted in accordance with Test Method D543.4.5 There are a number of factors influencing the physical properties and the retention of these properties after exposure. In addition to a complete description of the exposure test conditions used, the following information shall be included in any report referencing this practice: (1) complete description of the material tested, including the type, source, manufacturer's code number, form, and previous history; (2) methods of preparation for the material and individual test specimens; (3) procedure used for specimen conditioning prior to and after exposure; (4) complete description of the environment in which the physical properties were determined (for example, temperature and relative humidity); (5) complete description of the procedure used to determine the physical properties tested, including the rate at which specimens were tested, if applicable; (6) if applicable, void content of the specimens tested and the method used to measure void content.NOTE 2: It is not the intent of this practice to require users to divulge proprietary information regarding composition. To avoid divulging proprietary information, generic descriptions may be used to provide information on material composition.4.6 When destructive tests are used to determine a physical or chemical change, or both, which occurs as a result of exposure, the amount of change is expressed as a function of the value obtained for the material tested at a specified test environment (for example, temperature and humidity). The exposed and reference specimens are measured at the same time in the specified test environment.4.7 When nondestructive tests are used to determine a physical or chemical change, or both, which occurs as a result of exposure, the amount of change is expressed as a function of the value obtained on the specimens prior to exposure. Property measurement tests on the specimens before and after exposure shall be conducted at the same conditions (for example, temperature and humidity).4.8 The property or properties to be measured may be specified in an ASTM, ISO, or other appropriate standard for the material being tested, or by any prior agreement between interested parties. If the method used to measure the property being evaluated is not described in an ASTM, ISO, or other appropriate standard, a description of the test method shall be included in the report of test results.4.9 It is realized that a material cannot be tested without specifying the method of preparation. To have any meaning in comparative testing, specimens of each material being evaluated by these test procedures should be prepared or molded from the same lot under identical processing conditions and randomized prior to testing at the conditions desired. It must be realized that lot-to-lot variation in the material may cause additional variability in results.NOTE 3: For those plastics with a Tg greater than ambient, the slow collapse of free volume, with attendant significant changes in mechanical properties such as fatigue resistance, impact resistance, yield stress, and vapor transmission, etc. will be accelerated at elevated temperatures below the Tg but will be reversed at temperatures above the Tg. Therefore, incubation of material at elevated temperatures in the Tg range may be erratically susceptible to oven fluctuation effects.4.10 The results depend on which side of the test specimen is exposed with some tests. In bending tests, for example, different results are obtained in accordance with whether the exposed surface or the unexposed surface of the test specimen is placed under tension. Care must be taken to ensure that all specimens being exposed have the same orientation in the test fixture used to hold the specimens during exposure. In addition, the results also depend on the orientation of test specimens during the procedure used to measure the property being monitored. This is especially true with impact tests. During the procedure used to measure the characteristic property, care must be taken to ensure that all specimens are oriented the same way in the test fixture.4.11 Before proceeding with this practice, reference should be made to the specification of the material being tested. Any test specimen preparation, conditioning, or dimensions, or some combination thereof, and testing parameters covered in the material's specification shall take precedence over those mentioned in this practice. The default conditions described in this practice apply if there are no material specifications.1.1 This practice covers procedures for the calculation of a property retention index (PRI) of thermoplastic and thermoset plastics after exposure to thermal aging, natural or artificial accelerated weathering, or chemical exposures.1.2 This practice is not intended to establish a fixed procedure for conducting the exposure test, but it is intended to provide a set of specific procedures used to calculate the retention index of a characteristic property of the material after it has been exposed. Selection of the specific exposure test conditions depends on the material being tested and the property being measured. It is up to the user to determine which exposure test conditions are most relevant to the specific material and the service condition being used. The exposure test used must be conducted in accordance with conditions described in specific exposure standards.1.3 This practice does not describe procedures for sampling the materials to be tested. These procedures are described in the standards and specifications applicable to the material being evaluated.1.4 The procedure used to calculate the PRI depends on whether the test used to characterize the materials being exposed is destructive or nondestructive. The PRI can be useful in describing short-term mechanical, electrical, and other properties of plastics at specified temperatures after the materials have been subjected to an exposure test.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.NOTE 1: There is no similar or equivalent ISO standard. ISO 11248 is significantly different since it pertains only to thermosetting resins.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 guide is intended to present the elements of an approach for estimating layer moduli from deflection measurements that may then be used for pavement evaluation or overlay design. To characterize the materials in the layers of a pavement structure, one fundamental input parameter measured in the laboratory and used by some overlay design procedures is the resilient modulus. Deflection analysis provides a technique that may be used to estimate the in situ equivalent layer elastic moduli of a pavement structure as opposed to measuring the resilient moduli in the laboratory of small and sometimes disturbed samples. For many overlay design procedures that are based on layered elastic theory, the resilient modulus is approximated by this equivalent layer elastic modulus, because the equivalent modulus is determined as an average value for the total layer at the in situ stress conditions of an actual pavement.5.2 It should be emphasized that layer moduli calculated with this procedure are for a specific loading condition and for the environmental conditions at the time of testing. For these moduli to be used in pavement evaluations and overlay design, adjustments to a reference temperature, season, and design load may be required. These adjustments are not a part of this guide.5.3 The underlying assumption used in the solution is that a representative set of layer moduli exists for the particular loading condition (magnitude and area) and temperature condition, such that the theoretical or calculated deflection basin (using quasi-static layered elastic theory and the assumed static load characteristics of the NDT device) closely approximates the measured deflection basin. In reality, depending on the tolerance allowed in the procedure and the relative number of layers compared to the number of deflection sensors, several combinations of moduli may cause the two basins to “match” (or be within tolerance) reasonably well. A certain degree of engineering judgement is necessary to evaluate these alternative solutions and select the most applicable combination or eliminate unreasonable solutions, or both.5.4 There have been several studies that compared the results of various types of equipment and analysis methods; unfortunately, considerable variability has been noted. At this time, no precision estimate has been obtained from a statistically designed series of tests with different “known” materials and layer thicknesses. The back-calculated results do vary significantly with the various assumptions used in analysis to emulate the actual condition, as well as with the techniques used to produce and measure the deflections. Since the guide deals with a computerized analytical method, the repeatability is excellent if the input data and parameters remain the same. The bias of the procedure cannot be established at this time. The identity of the “true” in situ modulus, based on resilient modulus testing or some other field or laboratory test, needs to be standardized before the bias of the method can be established.1.1 This guide covers the concepts for calculating the in situ equivalent layer elastic moduli can be used for pavement evaluation, rehabilitation, and overlay design. The resulting equivalent elastic moduli calculated from the deflection data are method-dependent and represent the stiffnesses of the layers under a specific nondestructive deflection testing (NDT) device at that particular test load and frequency, temperature, and other environmental and site-specific conditions. Adjustments for design load, reference temperature, and other design-related factors are not covered in this guide. The intent of this guide is not to recommend one specific method, but to outline the general approach for estimating the in situ elastic moduli of pavement layers.1.2 This guide is applicable to flexible pavements and in some cases, rigid pavements (that is, interior slab loading), but is restricted to the use of layered elastic theory2 as the analysis method. It should be noted that the various available layered elastic computer modeling techniques use different assumptions and algorithms and that results may vary significantly. Other analysis procedures, such as finite element modeling, may be used, but modifications to the procedure are required.NOTE 1: If other analysis methods are desired, the report listed in Footnote 3 can provide some guidance.1.3 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.1.4 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.31.5 This guide offers an organized collection of information or a series of options and does not recommend a specific course of action. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of this guide may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a project's many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus process.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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4.1 The viscosity index is a widely used and accepted measure of the variation in kinematic viscosity due to changes in the temperature of a petroleum product between 40 °C and 100 °C.4.2 A higher viscosity index indicates a smaller decrease in kinematic viscosity with increasing temperature of the lubricant.4.3 The viscosity index is used in practice as a single number indicating temperature dependence of kinematic viscosity.4.4 Viscosity Index is sometimes used to characterize base oils for purposes of establishing engine testing requirements for engine oil performance categories.61.1 This practice2 covers the procedures for calculating the viscosity index of petroleum products, such as lubricating oils, and related materials from their kinematic viscosities at 40 °C and 100 °C.NOTE 1: The results obtained from the calculation of VI from kinematic viscosities determined at 40 °C and 100 °C are virtually the same as those obtained from the former VI system using kinematic viscosities determined at 37.78 °C and 98.89 °C.1.2 This practice does not apply to petroleum products with kinematic viscosities less than 2.0 mm2/s at 100 °C. Table 1 given in this practice applies to petroleum products with kinematic viscosities between 2 mm2/s and 70 mm2/s at 100 °C. Equations are provided for calculating viscosity index for petroleum products having kinematic viscosities above 70 mm2/s at 100 °C.1.2.1 In cases where kinematic viscosity data are not available at temperatures of 40 °C and 100 °C, an estimate may be made of the viscosity index by calculating the kinematic viscosity at temperatures of 40 °C and 100 °C from data obtained at other temperatures. Such viscosity index data may be considered as suitable for information only and not for specification purposes. See Test Method D341, Annex A1.1.3 The kinematic viscosity values are determined with reference to a value of 1.0034 mm2/s at 20.00 °C for distilled water. The determination of the kinematic viscosity of a petroleum product shall be carried out in accordance with Test Methods D445, D7042, IP 71, or ISO 3104.1.3.1 If Viscosity Index calculated for a given sample using kinematic viscosity measurements from different test methods are in disagreement, the values calculated from Test Method D445 measurements shall be accepted.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4.1 The values stated in SI units are to be regarded as the standard. For user reference, 1 mm2/s = 10-6m 2/s = 1 cSt.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 and health practices and determine the applicability of regulatory limitations prior to use.

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1.1 This test method covers determination of the normal and hemispherical emittance of a specular surface. This test method describes the spectrometric measurement of the near-normal specular reflectance in the mid-infrared range from 5 to at least 25 [mu]m. It includes the calculation procedures required to determine the normal and hemispherical emittance of said object. 1.2 This test method includes calibration instructions for the spectrometer and procedures for selecting reflectance-reference standards. 1.3 This test method is generally suitable for any flat, specular-reflecting specimen. It is recommended for measuring emittance of architectural glazing materials such as glass (coated and uncoated), etc. This test method is not suitable for determining the emittance of an object that is transparent in the specified range of infrared radiation. 1.4 This test method is suitable for determining the emittance of an object based on blackbody weighting at a specified temperature (typically 23°C (73°F)), as would be needed to determine the thermal performance (U-Value/ SC/SHGC) of a window assembly. 1.5 The values stated in SI units are to be regarded as the standard. The inch-pound units given in parentheses are for information only. 1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

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5.1 Thermogravimetry provides a rapid method for the determination of the temperature-decomposition profile of a material.5.2 This practice is useful for quality control, specification acceptance, and research.5.3 This practice is intended to provide an accelerated thermal endurance estimation in a fraction of the time require for oven-aging tests. The primary product of this practice is the thermal index (temperature) for a selected estimated thermal endurance (time) as derived from material decomposition.5.4 Alternatively, the estimated thermal endurance (time) of a material may be estimated from a selected thermal index (temperature).5.5 Additionally, the thermal endurance of a material at selected failure time and temperature may be estimated when compared to a reference value for thermal endurance and thermal index obtained from electrical or mechanical oven aging tests.5.6 This practice shall not be used for product lifetime predications unless a correlation between test results and actual lifetime has been demonstrated. In many cases, multiple mechanisms occur during the decomposition of a material, with one mechanism dominating over one temperature range, and a different mechanism dominating in a different temperature range. Users of this practice are cautioned to demonstrate for their system that any temperature extrapolations are technically sound.1.1 This practice describes the determination of thermal endurance, thermal index, and relative thermal index for organic materials using the Arrhenius activation energy generated for thermal decomposition measured by thermogravimetry.1.2 This practice is generally applicable to materials with a well-defined thermal decomposition profile upon heating, namely a smooth, continuous mass change.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, 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 Understanding the stability and compatibility of a petroleum product (crude oil or refinery stream, or both) is critical to facilities that receive multiple types of products and perform blending and processing operations. Blending incompatible streams can cause asphaltene precipitation with potential consequences such as but not limited to: refinery unit fouling, processing problems, throughput reduction, emulsion stabilization, pipeline and tank deposition, and equipment fouling.5.2 The ability to predict the results of blending operations allows operators to anticipate potential problems and mitigate those problems prior to receiving the products. It also helps facilities to manage their product movements in the most effective manner to avoid future issues.5.3 Some petroleum products are unstable without blending and understanding the stability of a product in terms of asphaltene precipitation is an important factor in product selection for refining. Products with poor stability can contribute to refinery unit fouling as well as the overall processibility and yield of that product.1.1 This test method covers the use of a basic microscope to determine the asphaltene solvency properties of bitumen, crude oil, condensate or related products, or the combinations thereof. These properties can be used to calculate the solubility parameters required to calculate and predict asphaltene stability for blending purposes, refinery unit fouling, processibility, emulsion stabilization, pipeline and tank deposition, and equipment fouling. If the solubility properties are known for two products, then the compatibility of potential blend ratios can be predicted.1.2 This test method is limited to products that allow handling at atmospheric pressure and room temperature conditions without a significant loss of light end components. Loss of light ends will result in changes in the solubility properties of the product and may alter or bias the results, or both. Samples with vapor pressures (VPCR4 at 37.8 °C using Test Method D6377) greater than 100 kPa are not suitable for use with this test method.1.3 This test method is primarily suited to products that are freely flowing at test conditions. Samples that are too viscous to flow at test conditions, such as semi-solids, may need to be heated to allow handling (See Annex A1.)1.4 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered 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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