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5.1 Although the determination of the washability characteristics of coal is not an exact science, this washability test method can be used to investigate the cleaning characteristics of coarse- and fine-coal fractions. However, especially with the fine-coal fractions, this test method may not be applicable for low-rank coals for reasons explained in 1.2.5.2 The usefulness of this test procedure and the usefulness of the results derived from washability testing are directly related to the care exercised in developing and following the sampling regime while taking into consideration the desired degree of precision. For more exacting work, it will be necessary to know the general washability characteristics of the material in question. This can be done only through pilot testing as described in 9.6 and Annex A3.5.3 This test method, in conjunction with the advice of experts and with knowledge of the particle size analysis (see Test Method D4749), is used for the engineering design of coal preparation facilities.5.4 This test method is also used to assist in process control and to determine the efficiency of operating preparation plants.5.5 This test method is used in core studies to determine the quality washability characteristics of coal reserves; however, in these instances the typical mass of raw coal from Table 1 may be neither applicable nor practical. For this reason, core diameter should be as large as possible and subdivision of the core section by any means or for any purpose prior to washability testing should be avoided. Care must be exercised in the design of the coring programs, including the consideration of appropriate geostatistics, in order that the potential recovery and quality of the coal reserves, as defined by the washability analysis of the cores, have any practical significance.1.1 This test method describes procedures for determining the washability characteristics of coarse-coal fractions and fine-coal fractions. Each sample being tested can have more than one coarse-coal size fraction and more than one fine-coal size fraction (see Annex A1). Each such size fraction has an upper size limit and a lower size limit, neither of which overlaps with the next larger nor smaller size fraction. (See Test Method D4749.)1.2 While, in general, this test method has useful application in determining the washability characteristics of low-rank coals, in the strictest sense, it is not necessarily the most technically correct test method to determine washability characteristics of low-rank coals because of problems relative to the loss of moisture through drying during sample preparation and analysis. Methods that are directly applicable to low-rank coals are to be developed.1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.1.4 This standard does not purport to address 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. For specific hazard statements, see Section 8 and Appendix X1.1.5 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 For matters relating to lot acceptance of commercial shipments and conformity to specification or other standard, refer to Section 13 of this test method.5.2 This test method is useful in the selection and design validation of permeable, uncoatable fabrics used in inflatable restraint cushions. The dynamic conditions and higher pressure differentials of this test method may better simulate the inflation and deflation cycle of an airbag module during deployment than do the steady-state conditions of Test Method D737.5.2.1 Only uncoated, permeable fabrics should be used. Use of coated fabrics may yield invalid results and potentially damage the test apparatus.5.3 Within the limits of variance expressed in Section 12, this test method is useful for design validation and may be suitable for incorporation in a material specification or for lot acceptance testing of commercial shipments. Caution is advised on very low permeability fabrics or with the 200 cm3 size test head because between-laboratory precision as presented in Section 12 may be as high as 21 %.5.4 This test method may be used for materials other than inflatable restraint fabrics which experience dynamic air permeability in sudden bursts. In such cases, the physical apparatus or its software algorithms may require modification to provide suitability for use.5.5 Due to the split-second time interval for testing, the pressure versus time data is subject to recording anomalies and electronic noise. The data should be digitally filtered to obtain the underlying smooth pressure curve prior to data analysis. The software in the apparatus includes a reliable algorithm both to smooth the curve and to determine the exponent of air permeability.5.6 It is inherent in the design and operation of this equipment that major components key to the calibration and measurements are specific to the individual test head. The size or permeability measuring range of the test head is typically chosen to correspond to the fabric specimen to be tested. The precision of this test method is highly dependent on the size of the test head. The precision of the data collected using one test head should be used to estimate the precision of data collected using a different test head, even on the same apparatus.5.7 It is mandatory that fabric specimens be conditioned and tested in standard atmosphere for testing textiles.1.1 This test method covers the procedures used to determine under dynamic airflow conditions the high pressure permeability of permeable, uncoated fabrics typically used for inflatable restraints. For the determination of air permeability of inflatable restraint fabrics under low pressure conditions at steady-state air flow, refer to Test Method D737.1.2 Procedures and apparatus other than those stated in this test method may be used by agreement of purchaser and supplier with the specific deviations from the standard acknowledged in the report.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 This test method is to be used as a quality control or quality assurance test. As a manufacturing quality control (MQC) test, it would generally be used by the geocomposite product manufacturer or fabricator. As a construction quality assurance (CQA) test, it would be used by certification or inspection organizations.5.2 This test method can also be used to verify if the adhesion or bond strength varies after exposure to various incubation media in durability or chemical resistance testing, or both.5.3 Whatever use is to be associated with the test, it should be understood that this is an index test.NOTE 2: There have been numerous attempts to relate the results of this test to the interface shearing resistance of the respective materials determined per Test Method D5321/D5321M. To date, no relationships have been established between the two properties.5.4 Test Method D7005/D7005M for determining the bond strength (ply adhesion) strength may be used as an acceptance test of commercial shipments of geocomposites, but caution is advised since information about between-laboratory precision is incomplete. Comparative tests as directed in 5.4.1 are advisable.5.4.1 In the case of a dispute arising from differences in reported test results when using the procedure in Test Method D7005/D7005M for acceptance of commercial shipments, the purchaser and the supplier should first confirm that the tests were conducted using comparable test parameters including specimen conditioning, grip faces, grip size, etc. Comparative tests should then be conducted to determine if there is a statistical bias between their laboratories. Competent statistical assistance is recommended for the investigation of bias. As a minimum, the two parties should take a group of test specimens that are as homogeneous as possible and that are from a lot of the material in question. The test specimens should be randomly assigned to each laboratory for testing. The average results from the two laboratories should be compared to the Student's t-test for unpaired data and an acceptable probability level chosen by the two parties before the testing is begun. If a bias is found, either its cause must be found and corrected or the purchaser and supplier must agree to interpret future test results in the light of the known bias. Refer to Practice D2905, Table 1.1.1 It has been widely discussed in the literature that bond strength of flexible multi-ply materials is difficult to measure with current technology. The above is recognized and accepted, since all known methods of measurement include the force required to bend the separated layers, in addition to that required to separate them. However, useful information can be obtained when one realizes that the bending force is included and that direct comparison between different materials, or even between the same materials of different thickness, cannot be made. Also, conditioning that affects the moduli of the plies will be reflected in the bond strength measurement.1.2 This index test method defines a procedure for comparing the bond strength or ply adhesion of geocomposites. The focus is on geotextiles bonded to geonets or other types of drainage cores, for example, geomats, geospacers, etc. Other possible uses are geotextiles adhered or bonded to themselves, geomembranes, geogrids, or other dissimilar materials. Various processes can make such laminates: adhesives, thermal bonding, stitch bonding, needling, spread coating, etc.1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.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. Specific precautionary statements are given in 11.1.1.1.5 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 General—Hydrogen sulfide is nearly ubiquitous. It occurs naturally in volcanic gases, in sulfur springs and fumaroles, in decaying of plant and animal protein, and in intestines as a result of bacterial action. Hydrogen sulfide is a serious hazard to the health of workers employed in energy production from hydrocarbon or geothermal sources, in the production of fibers and sheets from viscose syrup, in the production of deuterium oxide (heavy water), in tanneries, sewers, sewage treatment and animal waste disposal, in work below ground, on fishing boats, and in chemical operations, including the gas and oil industry.5.2 In 29 CFR 1910.1000, the Federal Occupational Safety and Health Administration designates that worker exposure to certain gases and vapors must not be exceeded in workplace atmospheres at concentrations above specific values, averaged over a certain time span. Hydrogen sulfide is included in this list. Refer also to NIOSH Criteria for a Recommended Standard, Occupational Exposure to Hydrogen Sulfide.5.3 This practice will provide means for the determination of airborne concentrations of hydrogen sulfide.5.4 This practice provides means for either personal or area sampling and for short-term or time-weighted average (TWA) measurements. Refer to Threshold Limit Values for Chemical Substances in the Work Environment.1.1 This practice covers the detection of hydrogen sulfide gas by visual chemical detectors. Included under visual chemical detectors are: short-term detector tubes (1),2 long-term detector tubes (2), and length-of-stain dosimeters (3). Diffusion tubes are not included under this practice because they are not direct reading, and spot tests are not included because of their poor accuracy. The sample results are immediately available by visual observation, thus no analytical equipment is needed.1.2 This practice reflects the current state-of-the-art for commercially available visual length-of-stain detectors for hydrogen sulfide. Any mention of a specific manufacturer in the text or references does not constitute an endorsement by ASTM.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

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5.1 The complex shear modulus of asphalt mixtures is a fundamental property of the material. Test results at critical temperatures (Tcritical) are used for specifications for some mixes. Mixtures with stiffer binders, aged mixes, mixtures with higher amounts of fines (material finer than 75 µ), and mixtures with lower voids all tend to have higher complex shear modulus values than mixtures with less stiff binders, unaged mixes, mixtures with low levels of fines, and higher air voids. In general, mixtures with higher complex shear modulus values at a given service temperature will exhibit lower permanent deformation values than similar mixtures tested at the same temperature that have lower complex shear modulus values.NOTE 2: The quality of the results produced by this standard are dependent on the competence of the personnel performing the procedure and the capability, calibration, and maintenance of the equipment used. Agencies that meet the criteria of Specification D3666 are generally considered capable of competent and objective testing, sampling, inspection, etc. Users of this standard are cautioned that compliance with Specification D3666 alone does not completely ensure reliable results. Reliable results depend on many factors; following the suggestions of Specification D3666 or some similar acceptable guideline provides a means of evaluating and controlling some of those factors.1.1 This test method covers the determination of the complex shear modulus of asphalt mixtures using torsion rectangular geometry on a dynamic shear rheometer (DSR). It is applicable to asphalt mixtures having complex shear modulus values greater than 1 × 104 Pa when tested over a range of temperatures from –40 °C to 76 °C at frequencies of 0.01 to 25 Hz and strains of 0.0005 % to 0.1 %. The determination of complex shear modulus is typically determined at 20 °C to 70 °C at 0.01 % strain at ten discrete frequency values covering 0.01 to 10 Hz. From these data, temperature or frequency master curves can be generated as required. This test method is intended for determining the complex shear modulus of asphalt mixtures as required for specification testing or quality control of asphalt mixture production.1.2 This test method is appropriate for laboratory-prepared and compacted mixtures, field-produced and laboratory-compacted mixtures or field cores, regardless of binder type or grade and regardless of whether RAP is used in the mixture. Due to the geometry of the specimens being tested this test method is not applicable to open-graded or SMA mixtures. It has been found to be appropriate for dense-graded mixtures, whether coarse- or fine-graded, with 19 mm or smaller nominal maximum aggregate size.1.3 Since a precision estimate for this standard has not been developed, the test method is to be used for research and informational purposes only. Therefore, this standard should not be used for acceptance or rejection of a material for purchasing purposes.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 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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