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AS 1889.1-1984 PVC floor tiles Semi-rigid 被代替 发布日期 :  1984-12-07 实施日期 : 

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5.1 This practice will identify waste materials that are potentially unstable when they come in contact with other materials at a waste treatment or disposal site.5.2 This practice will serve to determine the miscibility of waste materials with various media, including other wastes.5.3 This practice may not be applicable to all wastes. The appropriateness of these tests depends upon the proposed management of the waste.5.4 Since the initiation of some chemical reactions are slow to take place, the user may wish to establish reagent-to-waste contact times prior to observing the mixes for any reactions.1.1 This practice is designed to determine whether a waste material reacts when it is mixed with air, water, strong acid, strong base, an oil/solvent mixture, other waste mixtures, or solid media such as a geological formation or solidification agents.1.2 The miscibility of the waste material with the above media can also be defined.NOTE 1: The following ASTM standards provide supplemental information: Test Methods D4978, D4980, D4982, D5049, and D5057 and Practices D4979, D4981, and D5058.1.3 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. For specific hazard statements, see Section 8.1.5 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 The quantity and quality of the spores produced by this practice may be used to assess environmental surface disinfectants for sporicidal activity (4). The method is applicable to standard as well as clinically isolated toxigenic and non-toxigenic strains of C. difficile.1.1 This practice describes the production and semipurification of C. difficile spores (also called endospores) primarily for use in testing the sporicidal activities of environmental surface disinfectants (Test Methods E2111and E2197); such spores can also be used to study their structure, chemistry and germination.1.2 While the practice described is based on the use of 500-mL volumes of the liquid culture medium in an anaerobic incubator, anaerobic jars with smaller volumes of the same medium can also be used.1.3 It is the responsibility of the investigator to determine whether Good Laboratory Practice (GLP) regulations are required and to follow them when appropriate (40 CFR, Part 160 for EPA submissions and 21 CFR; Part 58 for FDA submissions).1.4 Warning—This standard may involve hazardous materials, chemicals, and microorganisms and should be performed only by persons with formal training in microbiology.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, 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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4.1 This practice provides a general procedure for the solvent extraction of volatile and semi-volatile organic compounds from a water matrix. Solvent extraction is used as the initial step in the solvent extraction of organic constituents for the purpose of quantifying extractable organic compounds.4.2 Typical detection limits that can be achieved using micro-extraction techniques with gas chromatography (GC) with flame ionization detector (FID), electron capture detector (ECD), or with a mass spectrometer (GC/MS) range from milligrams per litre (mg/L) to nanograms per litre (ng/L). The detection limit, linear concentration range, and sensitivity of the test method for a specific organic compound will depend upon the sample clean-up, injection volume, solvent to sample ratio, solvent concentration methods used, and the determinative technique employed.4.3 Micro-extraction has the advantage of speed, simple extraction devices, and the use of small amounts of sample and solvents.4.3.1 Selectivity can be improved by the choice of solvent (usually hexane or pentane) or mixed solvents, extraction time and temperature, and ionic strength of the solution.4.3.2 Extraction devices can vary from the sample container itself to commercial devices specifically designed for micro-extraction. See 7.1 and 7.2.4.3.3 A list of chlorinated organic compounds that can be determined by this practice includes both high and low boiling compounds or chemicals (see Table 1).(A) Based on the injection of chlorinated compounds in pentane solution, taking into consideration the 100:1 concentration of a water sample by the microextraction technique.1.1 This practice covers standard procedures for extraction of volatile and semi-volatile organic compounds from water using small volumes of solvents.1.2 The compounds of interest must have a greater solubility in the organic solvent than the water phase.1.3 Not all of the solvents that can be used in micro extraction are addressed in this practice. The applicability of a solvent to extract the compound(s) of interest must be demonstrated before use.1.4 This practice provides sample extracts suitable for any technique amenable to solvent injection such as gas chromatography or high performance liquid chromatography (HPLC).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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific hazard statements, see Section 91.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Values of density are used for converting volumes to units of mass and for correcting measured volumes at the measured temperature to a standard temperature using Practice D4311/D4311M.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 relative density and density of semi-solid asphalt materials, asphalt binders, asphalt cements, and soft-tar pitches by use of a digital density meter (U-tube).NOTE 1: Alternate methods for determining the density of semi-solid and solid asphalt materials and asphalt binders include Test Methods D3289, D3142/D3142M, and D70/D70M.1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only. No other units of measurement are included in this standard, with the exception of temperature measurements. Units provided in degrees Fahrenheit are for reference purposes only. Temperatures given in degrees Celsius are to be considered standard.1.3 This test method should not be applied to petroleum distillates other than asphalt and asphalt binders. For the determination of density of all other petroleum distillates and viscous oils, use Test Method D4052 or D5002, or ISO 12185.1.4 The text of this standard references notes and footnotes which provide explanatory material. These footnotes (excluding those in tables and figures) shall not be considered as requirements of the 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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5.1 Values of density are used for converting volumes to units of mass, and for correcting measured volumes from the temperature of measurement to a standard temperature using Practice D4311/D4311M.1.1 This test method covers the determination of the density of semi-solid and solid asphalt materials by weighing in air and in water.NOTE 1: An alternate method for determining the density of semi-solid and solid asphalt materials is Test Method D70/D70M. For materials which are too fluid for use of this method, use Test Method D3142/D3142M.1.2 The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard.1.3 Warning— Mercury has been designated by the United States Environmental Protection Agency (EPA) and many state agencies as a hazardous material that can cause central nervous system, kidney, and liver damage. Mercury or its vapor may be hazardous to health and corrosive to materials. Caution should be taken when handling mercury and mercury-containing products. See the applicable product Safety Data Sheet (SDS) for details and EPA’s website—www.epa.gov/mercury/faq.htm—for additional information. Users should be aware that selling mercury, mercury-containing products, or both, in your state may be prohibited by state law.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 Values of density are used for converting volumes to units of mass, and for correcting measured volumes from the temperature of measurement to a standard temperature using Practice D4311/D4311M.5.2 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 evaluation and controlling some of these factors.1.1 This test method covers the determination of the specific gravity (relative density) and density of semi-solid asphalt binder by use of a pycnometer.NOTE 1: An alternate method for determining the specific gravity or density of asphalt binder is Test Method D3289. An alternate method for determining density of asphalt binder is Test Method D8188. For materials which are too fluid for use of this test method, use Test Method D3142/D3142M.NOTE 2: This test method may also be used for the determination of the specific gravity (relative density) and density of soft tar pitches.1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the standard.1.3 Warning—Mercury has been designated by the United States Environmental Protection Agency (EPA) and many state agencies as a hazardous material that can cause central nervous system, kidney, and liver damage. Mercury, or its vapor, may be hazardous to health and corrosive to materials. Caution should be taken when handling mercury and mercury-containing products. See the applicable product Material Safety Data Sheet (MSDS) or Safety Data Sheet (SDS) for details and the EPA’s website (www.epa.gov/mercury/faq.htm) for additional information. Users should be aware that selling mercury, mercury-containing products, or both, in your state may be prohibited by state law.1.4 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.1.5 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 requirements to which flat-cast, amorphous, semi-processed, iron-base magnetic core alloys must conform. These alloys shall be produced by a rapid-quenching, direct-casting process, resulting in metals with noncrystalline structure. The alloys shall be made to meet specified maximum core-loss values and shall be intended primarily for commercial power frequency applications. Desirable core-loss and permeability characteristics shall be developed by further heat treatment in a magnetic field. Amorphous magnetic core alloys are normally composed of iron with small amounts of alloying elements such as boron and silicon. There are no specific chemical requirements in this specification. Material produced to this specification shall conform to the required physical and mechanical properties such as density, ductility, thermal expansion, thermal conductivity, volume resistivity, lamination factor, surface, edge, and pinholes. The alloy shall also conform to the magnetic property requirements such as DC induction, DC coercive field strength, DC residual induction, core loss, and specific exciting power.1.1 This specification covers the general requirements to which flat-cast, amorphous, semi-processed, iron-base magnetic core alloys must conform.1.2 These alloys are produced by a rapid-quenching, direct-casting process, resulting in metals with noncrystalline (amorphous) structure. The metallic alloys are made to meet specified maximum core-loss values and are intended primarily for commercial power frequency (50- and 60-Hz) applications in magnetic devices. Desirable core-loss and permeability characteristics are developed by further heat treatment in a magnetic field by the user. The heat treatment typically consists of heating the material to a temperature of 320 to 420°C in a dry, inert atmosphere for 5 to 10 min, although soak times of up to 2 h may be used for large transformer cores. A magnetic field may be required during annealing as designated by the producer. Exact optimum annealing conditions depend on the processing of the material and the size and shape of the device.1.3 Some of these alloys are sensitive to mechanical stress. Care must be exercised in minimizing any stresses on the material in its final application, otherwise, its magnetic properties will be significantly impaired.1.4 This specification is developed to aid in the purchase of transformer grade amorphous strip. It provides the chemical, physical, and magnetic parameters and procedures for quality control tests.1.5 The values stated in SI units are to be regarded as standard. The values given in parentheses are numerical conversions to customary (cgs and inch-pound) units which are provided for information only and are not considered standard.1.6 This standard does not purport to address the safety concerns associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 This practice provides a general procedure for the solid phase micro extraction of volatile and semi-volatile organic compounds from an aqueous matrix or its headspace. Solid sorbent extraction is used as the initial step in the extraction of organic constituents for the purpose of quantifying or screening for extractable organic compounds.5.2 Typical detection limits that can be achieved using SPME techniques with gas chromatography with flame ionization detector (FID), electron capture detector (ECD), or with a mass spectrometer (MS) range from mg/L to μg/L. The detection limit, linear concentration range, and sensitivity of the test method for a specific organic compound will depend upon the aqueous matrix, the fiber phase, the sample temperature, sample volume, sample mixing, and the determinative technique employed.5.3 SPME has the advantages of speed, no desorption solvent, simple extraction device, and the use of small amounts of sample.5.3.1 Extraction devices vary from a manual SPME fiber holder to automated commercial device specifically designed for SPME.5.3.2 Listed below are examples of organic compounds that can be determined by this practice. This list includes both high and low boiling compounds.Volatile Organic Compounds (1-3)3Pesticides, General (4, 5)Organochlorine Pesticides (6)Organophosphorous Pesticides (7, 8)Polyaromatic Hydrocarbons (9, 10)Polychlorinated Biphenyls (10)Phenols (11)Nitrophenols (12)Amines (13)5.3.3 SPME may be used to screen water samples prior to purge and trap extraction to determine if dilution is necessary, thereby eliminating the possibility of trap overload.1.1 This practice covers procedures for the extraction of volatile and semi-volatile organic compounds from water and its headspace using solid phase micro extraction (SPME).1.2 The compounds of interest must have a greater affinity for the SPME-absorbent polymer or adsorbent or combinations of these than the water or headspace phase in which they reside.1.3 Not all of the analytes that can be determined by SPME are addressed in this practice. The applicability of the absorbent polymer, adsorbent, or combination thereof, to extract the compound(s) of interest must be demonstrated before use.1.4 This practice provides sample extracts suitable for quantitative or qualitative analysis by gas chromatography (GC) or gas chromatography-mass spectrometry (GC-MS).1.5 Where used, it is the responsibility of the user to validate the application of SPME to the analysis of interest.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. For specific hazard statements, see Section 12.1.8 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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1.1 This specification covers preformed expansion joint fillers made from closed-cell polypropylene foam materials having suitable compressibility, recovery from compression, nonextruding, and weather-resistant characteristics.1.1.1 Type I, closed-cell polypropylene foam.1.2 These joint fillers are intended for use in concrete pavements in full-depth joints. There are several variations in size with typical thicknesses of 1/2 in. (12.7 mm), 3/4 in. (19.05 mm), and 1 in. (25.4 mm); typical widths of 31/2 in. (88.9 mm), 4 in. (101.6 mm), 5 in. (127 mm), 6 in. (152.5 mm), 7 in. (177.8 mm), 8 in. (203.2 mm), or 48 in. (1.2 m) sheet; and typical lengths of 5 ft (1.52 m) and 10 ft (3.05 m).1.3 The values stated in inch-pound units are to be regarded as the standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 Emissions of VOCs are typically controlled by internal mass-transfer limitations (for example, diffusion through the material), while emissions of SVOCs are typically controlled by external mass-transfer limitations (migration through the air immediately above the material). The emission of some chemicals may be controlled by both internal and external mass-transfer limitations. In addition, due to their lower vapor pressure, SVOCs generally adsorb to different media (chamber walls, building materials, particles, and other surfaces) at greater rates than VOCs. This sorption can increase the amount of time required to reach steady-state SVOC concentrations using conventional VOC emission test methods to months for a single test (2).4.2 Thus, existing methods for characterizing emissions of VOCs may not be appropriate or practical to properly characterize emission rates of SVOCs for use in modeling SVOC concentrations in indoor environments. A mass-transfer framework is needed to accurately assess emission rates of SVOCs when predicting the SVOC indoor air concentrations in indoor environments. The SVOC mass-transfer framework includes SVOC emission characteristics and its partition to multimedia including sorption to indoor surfaces, airborne particles, and settled dust. Once the SVOC emission parameters and partitioning coefficients have been determined, these values can be used to modeling SVOC indoor concentrations.1.1 This guide is intended to serve as a foundation for understanding when to use emission testing methods designed for volatile organic compounds (VOCs) to determine area-specific emission rates that are typically used in modeling indoor air VOC concentrations and when to use emission testing methods designed for semi-volatile organic compounds (SVOCs) to determine mass transfer emission parameters that are typically used to model indoor air, dust, and surface SVOC concentrations.1.2 This guide discusses how organic chemicals are conventionally categorized with respect to volatility.1.3 This guide presents a simplified mass-transfer model describing organic chemical emissions from a material to bulk air. The values of the model parameters are shown to be specific to material/chemical/chamber combinations.1.4 This guide shows how to use a mass-transfer model to estimate whether diffusion of the chemical within the material or convective mass transfer of the chemical from the surface of the material to the overlying air limits chemical emissions from the material surface.1.5 This guide describes the range of different chambers that are available for emission testing. The chambers are classified as either dynamic or static and either conventional or sandwich. The chambers are categorized as being optimal to determine either the area-specific emission rate or mass-transfer emission parameters.1.6 This guide discusses the roles sorption and convective mass-transfer coefficients play in selecting the appropriate emission chamber and analysis method to accurately and efficiently characterize emissions from indoor materials for use in modeling indoor chemical concentrations.1.7 This guide recommends when to choose an emission test method that is optimized to determine either the area-specific emission rate or mass-transfer emission parameters. For chemicals where the controlling mass-transfer process is unknown, the guide outlines a procedure to determine if the chemical emission is controlled by convective mass transfer of the chemical from the material.1.8 This guide does not provide specific guidance for measuring emission parameters or conducting indoor exposure modeling.1.9 Mechanisms controlling emissions from wet and dry materials and products are different. This guide considers the emission of chemicals from dry materials and products. Examples of functional uses of VOCs and SVOCs that this guide applies to include blowing agents, flame retardants, adhesives, plasticizers, solvents, antioxidants, preservatives, and coalescing agents (1).2 Emission estimations for other VOC and SVOC classes including those generated by incomplete combustion, spray application, or application as a powder (pesticides, termiticides, herbicides, stain repellents, sealants, water repellants) (1) may require different approaches than outlined in this guide because these processes can increase short-term concentrations of chemicals in the air independent of the volatility of the chemical and its categorization as a VVOC (very volatile organic compounds), VOC, SVOC, or NVOC (non-volatile organic compounds).1.10 The effects of the emissions (for example, exposure, and health effects on occupants) are not addressed and are beyond the scope of this guide.1.11 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.12 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.1.13 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 New and used petroleum products can contain basic constituents that are present as additives or as degradation products formed during service. The amount of these additives in an oil can be determined by titrating against an acid. The base number is a measure of the amount of basic substance in the oil, always under the conditions of the test. A decrease in base number is often used as a measure of lubricant degradation, but any condemning limits must be empirically established.5.2 This test method uses reagents that are considered less hazardous than most reagents used in alternate base number methods. It uses pre-packaged reagents to facilitate base number determinations in the field where scientific equipment is unavailable and quick results are at a premium.NOTE 1: Results obtained by this test method3 are similar to those obtained by Test Method D2896.1.1 This test method covers a procedure for determining the basic constituents in petroleum products in the field or laboratory using a pre-packaged test kit. The test uses a micro-titration resulting in a visual endpoint facilitated by a color indicator.1.1.1 This test method covers base numbers from 0 to 20. It can be extended to higher ranges by diluting the sample or by using a smaller sample size; however, the precision data were obtained for base numbers up to 20.1.2 This test method can be used to indicate relative changes that occur in an oil during use under oxidizing conditions. Although the test is performed under closely specified conditions with standardized reagents, the test method does not measure an absolute basic property that can be used to predict performance of an oil under service conditions. No general relationship between bearing corrosion and base number is known.1.3 The values stated in SI units are to be regarded as the standard.1.3.1 Exception—The values given in parentheses are 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, 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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This specification covers virgin poly(L-lactic acid) resin (PLLA resin) intended for use in surgical implants. This specification does not cover stereoisomeric compositions based on various D, L, or DL copolymer ratios. This specification addresses material characteristics of virgin poly(L-lactic acid) resin and does not apply to packaged and sterilized finished implants fabricated from this material. The virgin polymer shall be a homopolymer of L-lactide with the prescribed density. The molecular mass of the virgin polymer shall be indicated by relative solution viscosity (in chloroform). In addition, the weight average molecular mass and molecular mass distributions may be determined by gel permeation chromatography The virgin polymer shall be identified as a polylactide by infrared or 1H-NMR spectroscopy. Typical infrared transmission and 1H-NMR spectra are shown. The virgin polymer shall have a specific optical rotation (in dichloromethane) and residual monomer content within the prescribe values, and shall conform to the chemical and physical property requirements specified for: residual solvent, residual water, residual tin, heavy metals, and sulfated ash. The following test methods shall be used: (1) Karl-Fischer titration and (2) atomic absorption-emission (AA) spectroscopy or inductively coupled plasma (ICP) spectroscopy. Considerations for biocompatibility of the material from a human implant perspective is also given.1.1 This specification covers virgin semi-crystalline poly(l-lactide) or poly(d-lactide) homopolymer resins intended for use in surgical implants. This specification also covers semi-crystalline resins of l-lactide copolymerized with other bioabsorbable monomers including, but not limited to, glycolide, d-lactide, and dl-lactide. The poly(l-lactide) or poly(d-lactide) based homopolymers and copolymers covered by this specification possess lactide segments of sufficient length to allow potential for their crystallization upon annealing.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. Inclusion of stereoisomeric specificity within the lactic acid based acronyms results in the following: poly(l-lactide) as PlLA for poly(l-lactic acid), poly(d-lactide) as PdLA for poly(d-lactic acid), and poly(dl-lactide) as PdlLA for poly(dl-lactic acid).1.3 This specification is applicable to lactide-based polymers or copolymers that possess isotactic polymeric segments sufficient in size to carry potential for lactide-based crystallization. Such polymers typically possess nominal mole fractions that equal or exceed 50 % l-lactide. This specification is particularly applicable to isotactic-lactide based block copolymers or to polymers or copolymers synthesized from combinations of d-lactide and l-lactide that differ by more than 1.5 total mole percent (1.5 % of total moles). This specification is not applicable to lactide-co-glycolide copolymers with glycolide mole fractions greater than or equal to 70 % (65.3 % in mass fraction), which are covered by Specification F2313. This specification is not applicable to amorphous polymers or copolymers synthesized from combinations of d-lactide and l-lactide that differ by less than 1.5 total mole percent (1.5 % of total moles) as covered by Specification F2579.1.4 This specification covers virgin semi-crystalline poly(lactide)-based resins able to be fully solvated at 30 °C by either methylene chloride (dichloromethane) or chloroform (trichloromethane). This specification is not applicable to lactide: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 (see Specification F2313).1.5 Within this specification, semi-crystallinity within the resin is defined by the presence of a DSC (differential scanning calorimetry) crystalline endotherm after annealing above the glass transition temperature. While other copolymeric segments may also crystallize upon annealing (for example, glycolide), specific characterization of crystalline structures other than those formed by lactide are outside the scope of this specification.1.6 This specification addresses material characteristics of the virgin semi-crystalline poly(lactide)-based resins intended for use in surgical implants and does not apply to packaged and sterilized finished implants fabricated from these materials.1.7 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 ensure safety and efficacy.1.8 Biocompatibility testing is not a requirement since this specification is not intended to cover fabricated devices.1.9 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.10 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.1.11 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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