5.1 Ambient marine waters generally contain very low concentrations of toxic metals that require sensitive analytical methods, such as ICP-MS, to detect and measure the metal's concentrations.5.2 Due to the high dissolved salt concentrations present in seawater, sample pretreatment is required to remove signal suppression and significant polyatomic interferences due to the matrix both of which compromise detection limits.1.1 Toxic elements may be present in ambient waters and may enter the food chain via uptake by plants and animals; the actual concentrations of toxic metals are usually sub-ng/mL. The U.S. EPA has published its Water Quality Standards in the U.S. Federal Register 40 CFR 131.36, Minimum requirements for water quality standards submission, Ch. I (7-1-00 Edition), see Annex, Table A1.1. The U.S. EPA has also developed Method 1640 to meet these requirements, see Annex, Table A1.2.1.2 Inductively Coupled Plasma Mass Spectroscopy (ICP-MS) is a technique with sufficient sensitivity to routinely measure toxic elements in ambient waters, both fresh and saline (Test Method D5673). However saline and hard water matrices pose analytical challenges for direct multielement analysis by ICP-MS at the required sub-ng/mL levels.1.3 This practice describes a method used to prepare water samples for subsequent multielement analysis using ICP-MS. The practice is applicable to seawater and fresh water matrices, which may be filtered or digested. Samples prepared by this method have been analyzed by ICP-MS for the elements listed in Annex, Table A1.3).1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 Each year many thousands of water samples are collected and the chemical components are determined from natural and human-influenced groundwater sources.4.2 The objective interpretation of the origin, composition, and interrelationships of water can be simplified by displaying the distribution of the constituents and related parameters on areal maps (1,2).44.2.1 The origin of the chemical composition of the water may be postulated by the amount and the distribution of the constituents as shown on the maps.4.2.2 The chemical composition of the water can be scrutinized for distinct characteristics and anomalies by use of the maps.4.2.3 The interrelationships of the water chemistry from various sampling locations can be visualized on the maps.4.3 This guide presents various mapping methods for showing distribution of chemical constituents using areal and time-related trends; maximum, minimum, or mean values; and relationships between chemical and associated parameters.4.4 Exercise caution when interpreting the distribution of chemical constituents on two-dimensional (X and Y) maps as liquids of different densities tend to stratify in the third dimension (Z).NOTE 2: Water (or other liquid) with a relatively low concentration of dissolved solids (or of a low relative density) normally will float on top of water with high dissolved solids or a liquid of higher density (3-7). A naturally occurring example is an island surrounded and underlain by sea water where rain water falling on the island forms a fresh water lens above the underlying sea water. Where the presence of liquids of different densities are evident in a mapped area, cross sections of the aquifer assist in showing the vertical (Z) distribution of the chemical constituents or a pattern can be used on the map to delineate the extent of this water.NOTE 3: Immiscible liquid contaminants, such as petroleum products, with a relative density less than that of the water will float on top of the water. Liquids that are more dense than water will flow to the bottom of the aquifer. Miscible liquids, such as sea water, mix with the fresher water creating a zone of dispersion at the interface of the two liquids.4.5 Aquifers in fractured rock or karst areas may result in noncontinuum conditions for the chemical parameters in the water (Guide D5717). This guide assumes the aquifer usually consists of an equivalent porous media.4.6 This is not a guide for the selection of a map technique for a distinct purpose. That choice is program or project specific.NOTE 4: For many hydrochemical research problems involving the scientific interpretation of groundwater, the areal map is only one segment of several methods needed to interpret the data.1.1 This guide offers a series of options but does not specify a course of action. It should not be used as the sole criterion or basis of comparison and does not replace or relieve professional judgment.1.2 This guide covers methods that display, as mapped information, the chemical constituents of groundwater samples. Details required by the investigator to use fully the methods are found in the listed references.1.2.1 The use of maps to display water-quality data are a common technique to assist in the interpretation of the chemistry of water in aquifers, as the areally distributed values can be easily related to the physical locality by the investigator.1.2.2 The distribution in an aquifer of chemical constituents from two water sources or of liquids of different densities may be difficult to illustrate explicitly on a two-dimensional map because of stratification in the third dimension. Also, the addition of a vertical cross section may be required (see 4.4).1.3 Many graphic techniques have been developed by investigators to assist in summarizing and interpreting related data sets. This guide is the fourth document to inform the hydrologists and geochemists about traditional methods for displaying groundwater chemical data.1.3.1 The initial guide (Guide D5738) described the category of water-analysis diagrams that use pattern and pictorial methods as a basis for displaying each of the individual chemical components determined from the analysis of a single sample of natural groundwater.1.3.2 The second guide (Guide D5754) described the category of water-analysis diagrams that use two-dimensional trilinear graphs to display, on a single diagram, the common chemical components from two or more analyses of natural groundwater.1.3.3 The third guide (Guide D5877) presented methods that graphically display chemical analyses of multiple groundwater samples, discrete values, as well as those reduced to comprehensive summaries or parameters.1.4 Notations have been incorporated within the illustrations of this guide to assist the user in understanding how the maps are constructed. These notations would not be required on a map designed for inclusion in a project document.NOTE 1: Use of trade names in this guide is for identification purposes only and does not constitute endorsement by ASTM.1.5 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.

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5.1 This test method is suitable for determining the quantity of hydrogen peroxide, organic hydroperoxides, and organic peroxides as total active oxygen in various hydrocarbon streams for both quality control and quality assurance of the product.1.1 This test method covers the determination of trace peroxides in various hydrocarbon streams. A list of typical hydrocarbon streams can be found in Appendix X2.1.2 This test method is applicable to the determination of peroxides in petroleum liquids including, but not limited to, 1,3-butadiene, styrene, methylcyclohexane, and alpha olefins in the range of 0.1 mg/kg to 100 mg/kg active oxygen. The limit of detection (LOD) is 0.03 mg/kg for active oxygen and the limit of quantitation (LOQ) is 0.11 mg/kg active oxygen. The upper limit has been determined by the calibration range.NOTE 1: LOD and LOQ were calculated using data obtained during development of the method.1.3 In determining the conformance of the test results using this method to applicable specifications, results shall be rounded off in accordance with the rounding-off method of Practice E29.1.4 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific hazard statements, see Section 9.1.6 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 test method is intended for application in the semiconductor industry for evaluating the purity of materials (for example, sputtering targets, evaporation sources) used in thin film metallization processes. This test method may be useful in additional applications, not envisioned by the responsible technical committee, as agreed upon between the parties concerned.5.2 This test method is intended for use by GDMS analysts in various laboratories for unifying the protocol and parameters for determining trace impurities in pure titanium. The objective is to improve laboratory to laboratory agreement of analysis data. This test method is also directed to the users of GDMS analyses as an aid to understanding the determination method, and the significance and reliability of reported GDMS data.5.3 For most metallic species the detection limit for routine analysis is on the order of 0.01 weight ppm. With special precautions detection limits to sub-ppb levels are possible.5.4 This test method may be used as a referee method for producers and users of electronic-grade titanium materials.1.1 This test method covers the determination of concentrations of trace metallic impurities in high purity titanium.1.2 This test method pertains to analysis by magnetic-sector glow discharge mass spectrometer (GDMS).1.3 The titanium matrix must be 99.9 weight % (3N-grade) pure, or purer, with respect to metallic impurities. There must be no major alloy constituent, for example, aluminum or iron, greater than 1000 weight ppm in concentration.1.4 This test method does not include all the information needed to complete GDMS analyses. Sophisticated computer-controlled laboratory equipment skillfully used by an experienced operator is required to achieve the required sensitivity. This test method does cover the particular factors (for example, specimen preparation, setting of relative sensitivity factors, determination of sensitivity limits, etc.) known by the responsible technical committee to effect the reliability of high purity titanium analyses.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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5.1 Knowledge of the presence of trace metals in gas turbine fuels enables the user to predict performance and, when necessary, to take appropriate action to prevent corrosion.1.1 This test method covers the determination of sodium, lead, calcium, and vanadium in Specification D2880 Grade Nos. 0-GT through 4-GT fuels at 0.5 mg/kg level for each of the elements. This test method is intended for the determination of oil-soluble metals and not waterborne contaminants in oil-water mixtures.1.1.1 Test Method D6728 is suggested as an alternative test method for the determination of these elements in Specification D2880.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 The multidimensional approach permits all of the trace impurities to be well separated from the main vinyl chloride peak, thereby improving quantitative accuracy over established packed column methods.5.2 The minimum detection limit (MDL) for all components of interest has been shown to be well below 500 ppb for this test method.1.1 This is a general-purpose capillary-based test method for the determination of trace level impurities in high-purity vinyl chloride. This test method uses serially coupled capillary PLOT columns in conjunction with the multidimensional techniques of column switching and cryogenic trapping to permit the complete separation of the 11 key vinyl chloride impurities in a single 25-min run.NOTE 1: There is no known ISO equivalent to this standard.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. Specific hazards statements are given in Section 8.1.3 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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5.1 The U.S. Environmental Protection Agency Regulations, 40 CFR 266, require that boilers, cement kilns, and other industrial furnaces utilizing waste-derived fuel adhere to specific guidelines in assessing potential metals emissions. A common approach for estimating potential emissions is performing total metals analysis on all feed stream materials. This practice describes a multi-stage microwave-assisted digestion procedure that solubilizes trace elements for spectroscopic analyses.1.1 This practice describes the multi-stage microwave digestion of typical industrial furnace feed stream materials using nitric, hydrofluoric, hydrochloric, and boric acids for the subsequent determination of trace metals.1.2 This practice has been used successfully on samples of coal, coke, cement raw feed materials, and waste-derived fuels composed primarily of waste paint-related material in preparation for measuring the following trace elements: Ag, As, Ba, Be, Cd, Cr, Hg, Pb, Sb, and Tl. This practice may be applicable to elements not listed above.1.3 This practice is also effective for other waste materials (for example, fly ash, foundry sand, alum process residue, cement kiln dust, etc.).1.4 The values stated in SI units are to be regarded as standard. Other units of measurement in parentheses in this standard are informational.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. Specific hazard statements are given in Section 8.1.6 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 This test method permits the determination of very low levels of chloride ion in engine coolants containing the common corrosion inhibitor, mercaptobenzothiazole, or related mercaptans, which would normally interfere with the titration by also forming insoluble silver salts with silver nitrate.1.1 This test method covers the determination of chloride ion in engine coolants in the range from 5 ppm to 200 ppm in the presence of up to 0.6 weight % mercaptobenzothiazole.1.2 Other materials that react with silver ion will interfere.1.3 Chloride in engine coolants containing an aryltriazole instead of mercaptobenzothiazole can be determined directly by this test method without pretreatment with hydrogen peroxide.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific hazards statements are given in Section 7.1.6 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 Trace elemental analysis is used to indicate the level of contamination of middle distillate fuels. Trace metals in turbine fuels can cause corrosion and deposition on turbine components at elevated temperatures. Some diesel fuels have specification limit requirements for trace metals to guard against engine deposits. Trace level copper in middle distillate aviation turbine fuel can significantly accelerate thermal instability of the fuel, leading to oxidation and production of detrimental insoluble deposits in the engine.5.2 Gas turbine fuel oil Specification D2880 provides recommended upper limits for five trace metals (calcium, lead, sodium, potassium, and vanadium). Military specification MIL-DTL-16884 for naval distillate fuel sets requirements for maximum concentrations of the same five metals. Both specifications designate Test Method D3605, an atomic absorption/flame emission method, for the quantitative analysis of four of the metals. Test Method D3605 does not cover potassium. This test method provides an alternative to Test Method D3605, covers potassium and a number of additional elements.5.3 There are several sources of multi-element contamination of naval distillate fuel. Sea water is pumped into the diesel fuel tanks (as ballast) to trim ships. Also, some of the oilers (fuel supply ships) have dirty tanks. Corrosion products come from unlined tanks, piping, pumps, and heat exchangers.1.1 This test method covers the determination of selected elements in middle distillate fuels by inductively coupled plasma atomic emission spectrometry (ICP-AES). The specific elements are listed in Table 1. The concentration range of this test method is approximately 0.1 mg/kg to 2.0 mg/kg. The test method may be used for concentrations outside of this range; however, the precision statements may not be applicable. Middle distillate fuels covered in this test method have all distillation fractions contained within the boiling range of 150 °C to 390 °C. This includes, but is not limited to, diesel fuels and aviation turbine fuels.1.2 This test method is not intended to analyze insoluble particulates. However, very small particulate matter (smaller than a micrometre) will be carried into the plasma and be included in the quantitative analysis.1.3 This test method may give a result that is higher than the true value if an analyte is present in the sample in a form which is sufficiently volatile. For example, hexamethyldisiloxane will generate a biased high result for silicon.1.4 The values stated in SI units are to be regarded as 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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This method has been prepared to detect and quantitate nitrogen-containing compounds such as N-formylmorpholine (4-formylmorpholine, Chemical Abstract Service numbers (CAS) No. 250-37-6) or 1-methyl-2-pyrrolidinone (NMP) (CAS) No. 872-50-42 at a concentration of 1.0 mgN/kg or less in aromatic hydrocarbons used or produced in manufacturing processes. These nitrogen-containing compounds are undesirable in the finished aromatic products and may be the result of the aromatic extraction process. This test method may be used in setting specifications for determining the total nitrogen content in aromatic hydrocarbons. Note 1—Virtually all organic and inorganic nitrogen compounds will be detected by this technique. This technique will not detect diatomic nitrogen and it will produce an attenuated response when analyzing compounds (that is, s-triazine and azo compounds, etc.) that form nitrogen gas (N2) when decomposed. This test method requires the use of reduced pressure at the detector. Loss of vacuum or pressure fluctuations impact the sensitivity of the detector and the ability to determine nitrogen concentrations less than 1 mg/kg.1.1 This test method covers the determination of total nitrogen (organic and inorganic) in aromatic hydrocarbons, their derivatives and related chemicals. 1.2 This test method is applicable for samples containing nitrogen from 0.2 to 2 mgN/kg. For higher nitrogen concentrations refer to Test Method D 4629.1.2.1 The detector response of this technique within the specified scope of this test method is linear with nitrogen concentration.1.3 The following applies to all specified limits in this test method: for purposes of determining conformance with this test method, an observed value or a calculated value shall be rounded off "to the nearest unit" in the last right-hand digit used in expressing the specification limit, in accordance with the rounding-off method of Practice E 29.1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.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. For specific hazard statements, see Section 9.

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5.1 Elemental constituents in potable water, receiving water, and wastewater need to be identified for support of effective pollution control programs. Currently, one of the most sensitive and practical means for measuring low concentrations of trace elements is by graphite furnace atomic absorption spectrophotometry. ICP-MS may also be appropriate but at a higher instrument cost. See Test Method D5673.1.1 This practice covers the general considerations for the quantitative determination of trace elements in water and wastewater by graphite furnace atomic absorption spectrophotometry. Furnace atomizers are a most useful means of extending detection limits; however, the practice should only be used at concentration levels below the optimum range of direct flame aspiration atomic absorption spectrophotometry. Because of differences between various makes and models of satisfactory instruments, no detailed operating instructions can be provided for each instrument. Instead, the analyst should follow the instructions provided by the manufacturer of a particular instrument.1.2 Wavelengths, estimated detection limits, and optimum concentration ranges are given in the individual methods. Ranges may be increased or decreased by varying the volume of sample injected or the instrumental settings or by the use of a secondary wavelength. Samples containing concentrations higher than those given in the optimum range may be diluted or analyzed by other techniques.1.3 This technique is generally not applicable to brines and seawater. Special techniques such as separation of the trace elements from the salt, careful temperature control through ramping techniques, or matrix modification may be useful for these samples.1.4 The analyst is encouraged to consult the literature as provided by the instrument manufacturer as well as various trade journals and scientific publications.1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

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4.1 The anions fluoride, chloride, and sulfate have been identified as important contributors to corrosion of high pressure boilers, electric power turbines and their associated heat exchangers. Many electric power utilities attempt to reduce these contaminants in their boiler feed water to less than 1 μg/L.4.2 In the semiconductor manufacturing process these ions, among others, have been identified as a cause of low product yield and, thus, must be monitored and controlled to levels similar to those required by the electric power industry.4.3 Low molecular weight organic acids, such as acetate and formate, have been found in many steam generator feed waters and condensates. They are believed to come from the high temperature breakdown of organic matter found in boiler make up water. It is felt that these organic acids promote corrosion by lowering the pH of boiler waters and may even be corrosive themselves.4.4 Such low molecular weight organics may also be produced when ultraviolet light is used to produce bacteria-free water for semiconductor processing. Such polar organic contaminants are suspected of causing reduced semiconductor yields.4.5 Phosphates are commonly added to drum boilers in the low mg/L level to precipitate calcium and magnesium and thereby prevent scale formation. Ion chromatography can be used to monitor the concentration of such chemicals in boiler water, as well as detect unwanted carry-over into the steam.1.1 These test methods cover the determination of trace (μg/L) levels of fluoride, acetate, formate, chloride, phosphate, and sulfate in high purity water using ion chromatography in combination with sample preconcentration. Other anions, such as bromide, nitrite, nitrate, sulfite, and iodide can be determined by this method. However, since they are rarely present in significant concentrations in high purity water, they are not included in this test method. Two test methods are presented and their ranges of application, as determined by a collaborative study, are as follows:  Range Tested(μg/L Added) Limit of DetectionA(Single Operator)(μg/L) SectionsTest Method A:      7–16 Chloride 0–24  0.8   Phosphate 0–39  B   Sulfate 0–55  1.8  Test Method B:     17–24 Fluoride 0–14  0.7   Acetate 0–414 6.8   Formate 0–346 5.6  (A) Limit of detection is lowest measurable concentration not reportable as zero at 99 % level of confidence as per EPRI study as cited in Sections 16 and 24.(B) Insufficient data to calculate limit of detection.1.2 It is the user's responsibility to ensure the validity of these test methods for waters of untested matrices.1.3 The common practical range of Test Method A is as follows: chloride, 1 to 100 μg/L, phosphate, 3 to 100 μg/L, and sulfate, 2 to 100 μg/L.1.4 The common practical range of Test Method B is as follows: fluoride, 1 to 100 μg/L, acetate, 10 to 200 μg/L, and formate, 5 to 200 μg/L.1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

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4.1 This test method is suitable for setting specifications on benzene and for use as an internal quality control tool where benzene is either produced or used in a manufacturing process.4.2 This test method was found applicable for determining thiophene in refined benzene conforming to the specifications described in Specification D2359 and may be applicable toward other grades of benzene if the user has taken the necessary precautions as described in the text.1.1 This test method covers the determination of thiophene in refined benzene in the range from 0.80 to 1.80 mg/kg for the Flame Photometric Detector (FPD), and from 0.14 to 2.61 mg/kg for the Pulsed Flame Photometric Detector (PFPD). For the PFPD, the minimum level of quantitation (LOQ) is 0.14 mg/kg and the minimum level of detection (LOD) is 0.04 mg/kg, as described in ASTM Research Report RR:D16-1038.2 The range of the test method may be extended by modifying the sample injection volume, split ratios, calibration range, or sample dilution with thiophene-free solvent.1.2 This test method has been found applicable to benzene characteristic of the type described in Specifications D2359 and D4734 and may be applicable to other types or grades of benzene only after the user has demonstrated that the procedure can completely resolve thiophene from the other organic contaminants contained in the sample.1.3 The following applies to all specified limits in this test method: for purposes of determining conformance to applicable specification using this test method, an observed value or a calculated value shall be rounded off “to the nearest unit” in the last right-hand digit used in expressing the specification limit in accordance with the rounding-off method of Practice E29.1.4 The values stated in SI units are to be regarded as 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. For specific hazard statements, see Section 7.1.6 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 Low operating temperature fuel cells such as proton exchange membrane fuel cells (PEMFCs) require high purity hydrogen for maximum performance. The following are the reported effects (SAE TIR J2719) of the compounds determined by this test method.5.2 Carbon Dioxide (CO2), acts largely as a diluent; however, in the fuel cell environment, CO2 can be transformed into CO.5.3 Water (H2O), is an inert impurity, as it does not affect the function of a fuel cell stack; however, it provides a transport mechanism for water-soluble contaminants, such as Na+ or K+. In addition, it may form ice on valve internal surface at cold weather or react exothermally with metal hydride used as hydrogen fuel storage.5.4 Inert Gases (N2 and Ar), do not normally react with fuel cell components or fuel cell system and are considered diluents. Diluents can decrease fuel cell stack performance.5.5 Oxygen (O2), in low concentrations is considered an inert impurity, as it does not adversely affect the function of a fuel cell stack; however, it is a safety concern for vehicle on board fuel storage as it can react violently with hydrogen to generate water and heat.1.1 This test method describes a procedure primarily for the determination of carbon dioxide, argon, nitrogen, oxygen, and water in high pressure fuel cell grade hydrogen by gas chromatograph/mass spectrometer (GC/MS) with injection of sample at the same pressure as sample without pressure reduction, which is called “Jet Pulse Injection.” The procedures described in this method were designed to measure carbon dioxide at 0.5 micromole per mole (ppmv), Argon 1 ppmv, nitrogen 5 ppmv, oxygen 2 ppmv, and water 4 ppmv.1.2 Units—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.1.3 The mention of trade names in standard does not constitute endorsement or recommendation for use. Other manufacturers of equipment or equipment models can be used.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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Low operating temperature fuel cells such as proton exchange membrane fuel cells (PEMFCs) require high purity hydrogen for maximum material performance and lifetime. Sulfur compounds are present in many of the materials used in hydrogen production and small quantities typically remain after processing and purification. Part-per-billion concentrations of sulfur gases such as hydrogen sulfide (H2S), carbonyl sulfide (COS) and mercaptans diminish single fuel cell capacity.1.1 This test method describes a procedure primarily for the determination of hydrogen sulfide, carbonyl sulfide, methyl mercaptan, and carbon disulfide (Table 1) in hydrogen fuels for fuel cell vehicles (FCV) by gas chromatograph with sulfur chemiluminescence detection. The reporting limit is 0.02 ppbv (nanomole per mole as volume), based upon the analysis of a 500 mL hydrogen sample. The procedures described in this method were designed to satisfy sulfur contaminant determination requirements contained in SAE TIRJ2719 and the California Code of Regulations, CFR , Title 4, Division 9, Chapter 6, Article 8, Sections 4180 – 4181.1.2 This test method can be extended to other sulfur species in hydrogen fuel that are eluted through a chromatographic column.1.3 This test method can be modified to analyze all sulfur compounds present without chromatographic separation; thus, providing a total sulfur estimation without speciation (Appendix X1).1.4    If any new sulfur compounds need to be analyzed in hydrogen fuel, the calibration or spiking sulfur standards must include these new compounds after their method detection limit study. In addition, no co-elution is allowed in the chromatographic analysis of the calibration standard containing both the newly added and the existing sulfur target compounds. If necessary, the chromatographic conditions may be modified to achieve this goal.1.5 Although, primarily intended for determining sulfur in hydrogen used as a fuel for fuel cell or internal combustion engine powered vehicles, this test method can also be used to measure sulfur compounds in other gaseous fuels and gaseous matrices provided data quality objectives are satisfied.1.6 The values stated in SI units are standard. The values stated in inch-pound units are for information only.1.7 Mention of trade names in this standard does not constitute endorsement or recommendation for use. Other manufacturers of equipment or equipment models can be used.1.8 Alternative Detectors—This test method is written primarily for the use of sulfur chemiluminescent detectors but other detectors can be used provided they can detect hydrogen sulfide, carbonyl sulfide, methyl mercaptan, and carbon disulfide at 0.02 ppbv in hydrogen and meet data quality objectives for the intended use.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 and health practices and determine the applicability of regulatory limitations prior to use. For safety issues related to liquid nitrogen, refer to material safety data sheet (MSDS) from liquid nitrogen supplier.

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