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Low operating temperature fuel cells such as proton exchange membrane (PEM) fuel cells require high purity hydrogen for maximum material performance and lifetime. Analysis to part-per-billion (ppb) concentration of individual cation contaminants such as potassium, sodium and ammonium in hydrogen and related fuel cell supply gases is necessary for assuring a feed gas of sufficient purity to satisfy fuel cell system needs. More specifically, cations such as ammonium causes irreversible performance degradation of proton exchange membranes used in low temperature fuel cells by reacting with protons in the membrane to form ammonium ions.Although not intended for application to gases other than hydrogen and related fuel cell supply gases, techniques within this test method can be applied to other gaseous samples requiring cation analysis.1.1 This test method describes a procedure for the determination of cations in hydrogen and other fuel cell feed gases. It has been successfully applied to other types of gaseous samples including air, engine exhaust, and landfill samples. An ion chromatograph/conductivity detector (IC/CD) system is used to determine cations. Sensitivity from low part per billion (ppb, μg/l, μg/kg) up to part per million (ppm, mg/l, mg/kg) concentration are achievable dependant on the amount of hydrogen or other fuel cell gas sampled. This test method can be applied to other gaseous samples requiring analysis of trace constituents provided an assessment of potential interferences has been accomplished.1.2 The values stated in inch-pound units are to be regarded as standard. No other units of measurement are included in this standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

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5.1 This test method is intended to be used in specifications where porosity of cellular plastics has a direct bearing on their end use. For example, for thermal insulation applications, a high percentage of closed cells is necessary to prevent escape of gases and to promote low thermal conductivity. In flotation applications, high closed-cell content generally reduces water absorption.5.2 Before proceeding with this test method, reference shall be made to the specification of the material being tested. Any test specimen preparation, conditioning, or dimensions, or both, and testing parameters covered in the materials specification shall take precedence over those mentioned in this test method. If there are no material specifications, then the default conditions apply.1.1 This test method covers cellular plastics, which are composed of membranes or walls of polymer separating small cavities or cells. These cells may be interconnecting (open cell), non-connecting (closed cell), or any combination of these types. This test method determines numerical values for open cells. It is a porosity determination, measuring the accessible cellular volume of a material. The remaining volume is that occupied by closed cells and cell walls. Since any conveniently sized specimen is typically obtained by some cutting operation, a fraction of the closed cells will be opened by specimen preparation and will be included as open cells, (see Note 2).1.2 This test method provides good accuracy on predominantly highly open-celled materials. By not accounting for closed cells that were opened during specimen preparation, the accuracy decreases as the closed cell content increases and as the cell size increases.1.3 The values as stated in SI units are to be regarded as the standard. The values in parentheses are given for reference 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.NOTE 1: This test method and ISO 4590 use the same basic principles but are significantly different in experimental detail.NOTE 2: Two procedures for correcting for cells opened during specimen preparation are described in Appendix X1.1.1.5 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 Knowledge of extractives from flexible barrier materials may serve many useful purposes. A test cell constructed as described in this practice may be used for obtaining such data. Another test cell has been found equivalent to the one described in this practice. See the appendix for the source of the alternate cell.5.2 United States Federal Regulations 21CFR 176.170 (d)(3), 21CFR 177.1330 (e)(4), 21CFR 177.1360 (b), 21CFR 177.1670 (b), and 21CFR Appendix VI (b) cite this standard practice as the basis for determining the amount of extractables from the surface of a package or multilayer film or modified paper in contact with food. In some cases, it is the only practice defined for this purpose. No alternative detail is given in the regulations for conducting extractions.5.3 Test Method D4754 is not an equivalent to this test method. It is for two-sided extraction of films having the same material on both of the exposed surfaces of the film.1.1 This practice covers the construction of test cells which may be used for the extraction of components from flexible barrier materials by suitable extracting liquids, including foods and food simulating solvents.1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 This practice is useful for assessing the cytotoxic potential both when evaluating new materials or formulations for possible use in medical applications, and as part of a quality control program for established medical devices.5.2 This practice is used for assessing the cytotoxic potential of materials intended for the fabrication of inserts or implants in the orofacial region.5.3 This practice is restricted to normal non-transformed, human orofacial tissues using cells cultured in human serum factors and does not depend upon cells and serum from non-human sources.5.4 This practice incorporates procedures to monitor the quality of ingredient materials and the uniformity of the production process for formulating stock compositions.5.5 This practice may be useful to determine the effects of age and radiation, and the state of carcinogenicity on the sensitivity of HED tissues to materials and devices used for orofacial prostheses.1.1 This practice describes a procedure to assess the cytotoxic potential of materials for use in the construction of medical materials and devices using human excised donor (HED) tissues and their derived primary cells taken from the orofacial region.1.2 This practice may be used either directly to evaluate materials or as a reference against which other cytotoxicity methods may be compared.1.3 This practice is one of a series of reference methods for assessment of cytotoxic potential, employing different techniques.1.4 Assessment of cytotoxicity is one of several procedures employed in determining the biological response to a material, as recommended in Practice F748.1.5 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.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 Damage to pipe coating is almost unavoidable during transportation and construction. Breaks or holidays in pipe coatings may expose the pipe to possible corrosion since, after a pipe has been installed underground, the surrounding earth will be moisture-bearing and will constitute an effective electrolyte. Applied cathodic protection potentials may cause loosening of the coating, beginning at holiday edges. Spontaneous holidays may also be caused by such potentials. This test method provides accelerated conditions for cathodic disbondment to occur and provides a measure of resistance of coatings to this type of action.4.2 The effects of the test are to be evaluated by physical examinations and monitoring the current drawn by the test specimen. Usually there is no correlation between the two methods of evaluation, but both methods are significant. Physical examination consists of assessing the effective contact of the coating with the metal surface in terms of observed differences in the relative adhesive bond. It is usually found that the cathodically disbonded area propagates from an area where adhesion is zero to an area where adhesion reaches the original level. An intermediate zone of decreased adhesion may also be present.4.3 Assumptions associated with test results include:4.3.1 Maximum adhesion, or bond, is found in the coating that was not immersed in the test liquid, and4.3.2 Decreased adhesion in the immersed test area is the result of cathodic disbondment.4.4 Ability to resist disbondment is a desired quality on a comparative basis, but disbondment in this test method is not necessarily an adverse indication of coating performance. The virtue of this test method is that all dielectric-type coatings now in common use will disbond to some degree, thus providing a means of comparing one coating to another.4.5 The current density appearing in this test method is much greater than that usually required for cathodic protection in natural environments.1.1 This test method covers accelerated procedures for simultaneously determining comparative characteristics of coating systems applied to steep pipe exterior for the purpose of preventing or mitigating corrosion that may occur in underground service where the pipe will be in contact with natural soils and will receive cathodic protection. They are intended for use with samples of coated pipe taken from commercial production and are applicable to such samples when the coating is characterized by function as an electrical barrier.1.2 This test method is intended to facilitate testing of coatings where the test cell is cemented to the surface of the coated pipe specimen. This is appropriate when it is impractical to submerge or immerse the test specimen as required by Test Methods G8, G42, or G80. Coating sample configuration such as flat plate and small diameter pipe may be used, provided that the test procedure remains unchanged.21.3 This test method allows options that must be identified in the report.1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.5 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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This specification covers flexible closed-cell or non-interconnecting cellular products, the elastomer content of which is predominantly poly(vinyl chloride) foam or copolymers thereof. Materials shall be produced in sheet, strip, molded, or simple specific shapes. Complete details about apparatuses needed, specimen preparation, and procedures for the testing of compression deflection, compression set under constant deflection, and water absorption are thoroughly itemized.1.1 This specification covers flexible closed-cell or non-interconnecting cellular products, the elastomer content of which is predominantly poly(vinyl chloride) or copolymers thereof.1.2 In the case of conflict between the provisions of this specification and those of detailed specifications or methods of test for a particular product, the latter shall take precedence.1.3 Reference to the methods for testing closed-cell poly(vinyl chloride) contained herein shall specifically state the particular test or tests desired and not refer to these methods of test as a whole.1.4 The values stated in SI units are to be regarded as the standard. The inch-pound units given in parentheses are for information only.1.5 The following precautionary statement pertains to the test method portions only of this specification: This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.NOTE 1: There is no known ISO equivalent to this standard.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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1.1 This specification covers requirements, test methods, materials, and marking for closed-cell cellular polypropylene (PP), open bottom, buried chambers of corrugated wall construction used for collection, detention, and retention of stormwater runoff. Applications include commercial, residential, agricultural, and highway drainage, including installation under parking lots and roadways.1.2 Chambers are produced in arch shapes with dimensions based on chamber rise, chamber span, and wall stiffness. Chambers are manufactured with integral feet that provide base support. Perforations to enhance water flow are permitted. Chambers must meet test requirements for arch stiffness, and flattening. Chamber end caps shall be produced of PP or polyethylene (PE) by a suitable manufacturing process provided that all other product requirements in this standard are met.1.3 Analysis and experience have shown that the successful performance of this product depends upon the type and depth of bedding and backfill, and care in installation. This specification includes requirements for the manufacturer to provide chamber installation instructions to the purchaser.1.4 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.1.5 This standard does not purport to address water quality issues or hydraulic performance requirements associated with its use. It is the responsibility of the user to ensure that appropriate engineering analysis is performed to evaluate the water quality issues and hydraulic performance requirements for each installation.1.6 The following safety hazards caveat pertains only to the test method portion, Section 6, of this specification: This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, 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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1.1 Cellular plastics are composed of the membranes or walls of polymer separating small cavities or cells. These cells may be interconnecting (open cell), non-connecting (closed cell), or any combination of these types. This test method determines numerical values for open cells. It is a porosity determination, measuring the accessible cellular volume of a material. The volume occupied by closed cells is considered to include cell walls. Since any conveniently sized specimen can only be obtained by some cutting operation, a fraction of the closed cells will be opened during sample preparation and will be included as open cells. 1.2 This test method consists of three procedures: 1.2.1 Procedure A , designed to correct for cells opened during sample preparation, by measuring cell diameter, calculating, and allowing for surface volume; 1.2.2 Procedure B , designed to correct for cells opened in sample preparation, by cutting and exposing new surface area equal to the surface area of the original sample dimension, and 1.2.3 Procedure C , which does not correct for cells opened during sample preparation and gives good accuracy on predominantly highly open-celled materials. The accuracy decreases as the closed cell content increases and as the cell size increases. 1.3 The values as stated in SI units are to be regarded as the standard. The values in parentheses are given for information only. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in Notes 2, 4, and 8. Note 1-This test method and ISO 4590-1981 use the same basic principles but are significantly different in experimental detail.

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