5.1 The determination of compound types by mass spectrometry requires, in some instances, a preliminary separation of the petroleum sample into representative aromatics and nonaromatics fractions, as in Test Methods D2425, D2786, and D3239. This test method provides a suitable separation technique for this application.1.1 This test method covers the separation and determination of representative aromatics and nonaromatics fractions from hydrocarbon mixtures that boil between 232 °C and 538 °C (450 °F and 1000 °F). Alternative procedures are provided for the separation of 2 g or 10 g of hydrocarbon mixture.NOTE 1: Some components may not be eluted from the chromatographic column for some types of samples under the conditions used in this method.NOTE 2: Test Method D2007 is an alternative method of separating high-boiling oils into polar compounds, aromatics, and saturates fractions.1.2 An alternative procedure is provided to handle samples boiling below 232 °C (450 °F), but whose 5 % point is above 178 °C (350 °F) as determined by Test Method D2887. This procedure is given in Appendix X1.1.3 The values stated in acceptable SI units are to be regarded as the standard. The values given in parentheses are provided for information purposes only.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 This guide is intended to provide the conventions adopted by the International Standards Organization (ISO 7708), the Comité Européen de Normalisation (CEN EN 481), and the American Conference of Governmental Industrial Hygienists (ACGIH) (1). The definition of respirable aerosol is the basis for recommended exposure levels (REL) of respirable coal mine dust as promulgated by NIOSH (Criteria for a Recommended Standard, Occupational Exposure to Respirable Coal Mine Dust (15)). The respirable aerosol definition also forms the basis of the NIOSH sampling method for respirable particulates not otherwise regulated (NIOSH Manual of Analytical Methods (16)).4.2 The convention can be used for those who are preparing to evaluate a workplace environment by collecting samples of aerosolized particles, or who wish to obtain an understanding of what information can be obtained by such sampling. The convention to be used is not always straightforward, but generally depends on what part of the respiratory system is affected by the aerosol particles. The conventions are often applied for approximating mass fractions, but they may also be used in the evaluation of total surface area or the number of particles in the collected material.4.3 The conventions constitute a part of the performance characteristics required of aerosol samplers for collecting aerosol according to the relevant health effects. This guide therefore does not specify particular samplers for measuring the aerosol fractions defined here. Detailed guidelines for evaluating any given sampler relative to the conventions are available (CEN EN 13205, six parts). Several advantages over instrument specification can be attributed to the adoption of these performance-associated conventions:4.3.1 The conventions have a recognized relationship to health effects.4.3.2 Performance criteria permit instrument designers to seek practical sampler improvements.4.3.3 Performance criteria promote continued experimental testing of the samplers in use with the result that the significant variables (such as wind speed, particle charge, and so forth) affecting sampler operation become understood.1.1 This guide defines conventions for personal samplers of specific particle-size-dependent fractions of any given non-fibrous airborne aerosol. Such samplers are used for assessing health effects and in the setting of and testing for compliance with permissible exposure limits in the workplace and ambient environment. The conventions have been adopted by the International Standards Organization (ISO 7708), the Comité Européen de Normalisation (CEN EN 481), and the American Conference of Governmental Industrial Hygienists (ACGIH) (1).2 The conventions were developed (2) in part from health-effects studies reviewed (3) by the ACGIH and in part as a compromise between definitions proposed by the ACGIH (3) and by the British Medical Research Council (BMRC) (4). Conventions are given here for inhalable, thoracic, and respirable fractions.1.2 This guide is complementary to Test Method D4532, which describes the performance of respirable dust cyclones and operational procedures for use. The procedures, specifically the optimal flow rate, are still valid although the estimated accuracy differs somewhat from use with previous aerosol fraction definitions. Details on these instruments have been published (5-11).1.3 Limitations: 1.3.1 The definitions given here were adopted by the agencies listed in 1.1 in part on the basis of expected health effects of the different size fractions, but in part allowing for available sampling equipment. The original adoption by CEN was, in fact, for the eventual setting of common standards by the EC countries while permitting the use of a variety of instrumentation. Deviations of the sampling conventions from health-related effects are as follows:1.3.1.1 The inhalable fraction actually depends on the specific air speed and direction, on the breathing rate, and on whether breathing is by nose or mouth. The values given in the inhalable convention are for representative values of breathing rate and represent averages over all wind directions.1.3.1.2 The respirable and thoracic fractions vary from individual to individual and with the breathing pattern. The conventions are approximations to the average case.1.3.1.3 Each convention applies strictly to a fraction penetrating to a region, rather than depositing. Therefore, samples collected according to the conventions may only approximate correlations with biological effects. For example, the respirable convention overestimates the fraction of very small particles deposited in the alveolar region of the respiratory system because some of the particles are actually exhaled without being deposited (12). In many workplaces, these very small particles contribute insignificantly to the sampled mass. Furthermore, the large variability between individuals and the details of clearance may be as important as this type of effect.1.3.1.4 The thoracic convention applies to mouth breathing, for which aerosol collection is greater than during nose breathing.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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This specification covers the material characteristics of virgin poly(glycolide) and poly(glycolide-co-lactide) resins with mole fractions within the specified range used in surgical implants. This does not cover packaged and sterilized finished implants fabricated from the same materials. Since some characteristics may be altered by processing techniques when used to produces a specific part or device, properties of fabricated forms of the resins should be evaluated independently using appropriate test methods. The identity of the poly(glycolide) homopolymer, poly(glycolide-co-lactide) copolymer, and poly(glycolide-co-lactide) polymer must be confirmed through nuclear magnetic resonance (NMR).1.1 This specification covers both virgin poly(glycolide) homopolymer and poly(glycolide-co-lactide) copolymer resins intended for use in surgical implants. The poly(glycolide-colactide) copolymers covered by this specification possess nominal mole fractions greater than or equal to 70 % glycolide (65.3 % in mass fraction). This specification is also applicable to lactide-co-glycolide copolymers that possess glycolide segments sufficient in size to deliver potential for glycolide-based crystallization, thereby requiring fluorinated solvents for complete dissolution under room temperature conditions.1.2 Since poly(glycolide) is commonly abbreviated as PGA for poly(glycolic acid) and poly(lactide) is commonly abbreviated as PLA for poly(lactic acid), these polymers are commonly referred to as PGA, PLA, and PLA:PGA resins for the hydrolytic byproducts to which they respectively degrade. PLA is a term that carries no stereoisomeric specificity and therefore encompasses both the amorphous atactic/syndiotactic dl-lactide-based polymers and copolymers as well as the isotactic d-PLA and l-PLA moieties, each of which carries potential for crystallization.1.3 This specification is specifically not applicable to amorphous poly(lactide-co-glycolide) or poly(lactide)-based resins able to be fully solvated at 30°C by either methylene chloride (dichloromethane) or chloroform (trichloromethane), which are covered in Specification F2579 and typically possess molar glycolide levels of ~50 % or less. This specification is not applicable to lactide-based polymers or copolymers that possess isotactic polymeric segments sufficient in size to carry potential for lactide-based crystallization, which are covered by Specification F1925 and typically possess nominal mole fractions that equal or exceed 50 % l-lactide.1.4 This specification addresses material characteristics of both virgin poly(glycolide) and poly(>70 % glycolide-co-lactide) resins intended for use in surgical implants and does not apply to packaged and sterilized finished implants fabricated from these materials.1.5 As with any material, some characteristics may be altered by processing techniques (such as molding, extrusion, machining, assembly, sterilization, and so forth) required for the production of a specific part or device. Therefore, properties of fabricated forms of this resin should be evaluated independently using appropriate test methods to assure safety and efficacy.1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 Knowledge of the hydrogen content of petroleum products, particularly fuels, can be helpful in assessing performance characteristics.4.2 This test method is suitable for most laboratory applications requiring the determination of hydrogen in liquid petroleum lubricants and products.1.1 This test method covers the determination of hydrogen in petroleum fractions that can be burned completely without smoking in a wick lamp.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 and health practices and determine the applicability of regulatory limitations prior to use.

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1.1 This test method covers a convenient and accurate means of determining the specific gravity of (1) creosote fractions entirely liquid at 38°C, (2) creosote fractions containing solids at 38°C, and ( 3) distillation residues. It is also suitable for determining the specific gravity of oil-type preservatives when the quantity available is too small for the hydrometer method as given in Test Method D 368. Test Methods D 38 cover the sampling of wood preservatives prior to testing.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 and health practices and determine the applicability of regulatory limitations prior to use.

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The determination of the boiling range distribution of gasoline by GC distillation provides an insight into the composition of the components from which the gasoline has been blended. This insight also provides essential data necessary to calculate the vapor pressure of gasoline, which has been traditionally determined by Test Method D 323. In addition, the Test Method D 86 distillation curve can be predicted using GCD data. See Annex A1.The GCD method facilitates online controls at the refinery, and its results offer improved means of describing several car performance parameters. These parameters include: (1) car-starting index, (2) vapor-lock index or vapor-liquid ratio, and (3) warm-up index. The car-starting and vapor-lock indexes have been found to be mostly affected by the front end of the Test Method D 86 distillation curve (up to about 200°F (93°C)). The warm-up index is affected by the middle and to a lesser extent by the back end of the Test Method D 86 curve, that is, the temperatures corresponding to the 50 to 90 % off range. Since the boiling range distribution provides fundamental information on composition, an improved expression for the above performance parameters may be worked out, even when the boiling range distribution curve is not smooth. Currently, car performance cannot be assessed accurately under such conditions.1.1 This test method covers the determination of the boiling range distribution of gasoline and gasoline components. This test method is applicable to petroleum products and fractions with a final boiling point of 500°F (260°C) or lower as measured by this test method.1.2 This test method is designed to measure the entire boiling range of gasoline and gasoline components with either high or low Reid vapor pressure and is commonly referred to as gas chromatography (GC) distillation (GCD).1.3 This test method has not been validated for gasolines containing oxygenated compounds (for example, alcohols or ethers).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 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 Note 9 and 7.2.

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