4.1 High-purity ethylene is required as a feedstock for some manufacturing processes, and the presence of trace amounts of carbon dioxide and some hydrocarbons can have deleterious effects. This method is suitable for setting specifications, for use as an internal quality control tool and for use in development or research work.1.1 This test method covers the determination of carbon dioxide, methane, ethane, acetylene, and other hydrocarbons in high-purity ethylene. Hydrogen, nitrogen, oxygen, and carbon monoxide are determined in accordance with Test Method D2504. The percent ethylene is obtained by subtracting the sum of the percentages of the hydrocarbon and nonhydrocarbon impurities from 100. The method is applicable over the range of impurities from 1 to 500 parts per million volume (ppmV).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. For some specific hazard statements, see Section 6.1.3 The values stated in SI units are to be regarded as the standard. The values in parentheses are for information only.

定价： 590元 / 折扣价： 502 元 加购物车

5.1 Acceptance Testing—This method of testing fabrics resistance to pilling is not recommended for acceptance testing. If it is used for acceptance testing, it should be used with caution because interlaboratory data are not available. In some cases the purchaser or supplier may have to test a commercial shipment of one or more specific materials by the best available method even though the method has not been recommended for acceptance testing. Although this test method is not recommended for acceptance testing, it is useful because it is used widely outside the United States.5.2 If there is a disagreement arising from differences in values reported by the purchaser and the supplier when using this test method, the statistical bias, if any, between the laboratory of the purchaser and the laboratory of the supplier should be determined with comparison being based on testing specimens randomly drawn from one sample of material of the type being evaluated. Competent statistical assistance is recommended for the investigation of bias. A minimum of two parties should take a group of test specimens, which are as homogeneous as possible and which are from a lot of material of the type in question. The test specimens then should be assigned randomly in equal numbers to each laboratory for testing. The average test results from the two laboratories should be compared using an acceptable statistical protocol and probability level chosen by the two parties before the testing is started. Appropriate statistical disciplines for comparing data must be used when the purchaser and supplier cannot agree. If a bias is found, either its cause must be found and corrected, or the purchaser and the supplier must agree to interpret future results with consideration for the known bias.5.3 The pilling of textile fabrics is a very complex property because it is affected by many factors that include type of fiber or blends, fiber dimensions, yarn and fabric construction, and fabric finishing treatments. The pilling resistance of a specific fabric in actual wear varies more with general conditions of use and individual wearers than in replicate fabric specimens subjected to controlled laboratory tests. This experience should be borne in mind when adopting levels of acceptability for a series of standards.5.4 Finishes and fabric surface changes may exert a large effect on pilling. Fabrics may be tested as received or after refurbishing, or both (laundering or drycleaning, or both). Interested parties shall agree on the state of fabric to be tested. The state of tested fabric shall be reported..5.5 Pills vary appreciably in size and appearance and depend on the presence of lint and degree of color contrast. These factors are not evaluated when pilling is rated solely on the number of pills. The development of pills may be accompanied by other surface phenomena, such as loss of cover, color change, or the development of fuzz. Since the overall acceptability of a specific fabric is dependent on both the characteristics of the pills and the other factors affecting the surface appearance, it is suggested that fabrics tested in the laboratory be evaluated subjectively with regard to their acceptability and not rated solely on the number of pills developed. A series of standards, based on graduated degrees of surface change of the fabric type being tested, may be set up to provide a basis for subjective ratings. The visual standards are most advantageous when the laboratory test specimens correlate closely in appearance with worn fabrics and show a similar ratio of pills to fuzz. Counting the pills and weighing their number with respect to their size and contrast, as a combined measure of pilling resistance, is not recommended because of the excessive time required for counting, sizing, and calculation.5.6 The degree of fabric pilling is evaluated by comparing the tested specimens with visual standards, which may be actual fabrics or photographs of fabrics, showing a range of pilling resistance. The observed resistance to pilling is reported on an arbitrary scale ranging from 5 to 1 (no pilling to very severe pilling).5.7 This test method is applicable to a wide variety of woven and knitted fabrics that vary in pilling propensity as a result of variations in fiber, yarn and fabric structure, and finish. The applicability of this test method to nonwoven fabrics has not been determined.1.1 This test method covers the determination of the resistance to the formation of pills and other related surface changes on textile fabrics using the Martindale tester.NOTE 1: For other methods, if testing the pilling resistance of textiles, refer to Test Methods D3511/D3511M, D3512/D3512M, and D3514.1.2 This test method is generally applicable to knit, woven, and nonwoven fabrics; however, material thickness may limit suitability for testing due to specimen holder capacity.1.3 The fabric may be laundered or dry cleaned before testing as agreed upon among interested parties.1.4 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 non-conformance with 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.

定价： 590元 / 折扣价： 502 元 加购物车

This specification covers one grade of virgin zirconium metal commonly designated as sponge because of its porous, sponge-like texture, but it may also take other forms such as chunklets. The one grade described is designated as Reactor Grade R60001, suitable for use in nuclear applications. The main characteristic of the reactor grade is its low nuclear cross section as achieved by removal of hafnium. Zirconium metal is usually prepared by reduction of zirconium tetrachloride, and gets its physical characteristics from the processes involved in production. These characteristics may be expected to vary greatly with manufacturing methods. Only virgin zirconium metal, in identified, uniform, well-mixed blends, shall be used. The zirconium metal shall conform to the requirements for chemical composition specified.1.1 This specification covers one grade of virgin zirconium metal commonly designated as sponge because of its porous, sponge-like texture, but it may also take other forms such as chunklets, suitable for use in nuclear applications.1.2 Unless a single unit is used, for example corrosion mass gain in mg/dm2, the values stated in either inch-pound or SI units are to be regarded separately as standard. The values stated in each system are not exact equivalents; therefore each system must be used independently of the other. SI values cannot be mixed with inch-pound values.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.

定价： 515元 / 折扣价： 438 元 加购物车

1.1 This test method covers the gravimetric determination of phthalic anhydride in alkyd resins and esters that contain dibasic acids such as maleic, fumaric, adipic, and sebacic, which would interfere if Test Method D 563 was used.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.

定价： 0元 / 折扣价： 0 元

5.1 This test method provides a means of accelerating the tendency of a material toward spontaneous heating that may eventually lead to a fire. It is applicable to liquids and pastes.5.2 The spontaneous heating behavior of an oil-based material is affected by such factors as the availability of oxygen, the amount of driers present, the degree of polymerization of oils, the surface area of the cellulose material, measures to prevent heat dissipation, and the amount of oil in contact with cellulose material. The degree of spontaneous heating bears little relationship to the type of cellulose material to which an oil-based material comes in contact or whether or not oil soaked materials are first air dried. Small amounts of contaminants, such as oil paint, quartz dust, dirt or drier (for example, materials that might be found on a dirty, oil-soaked rag), can act as catalysts for this reaction.41.1 This test method covers a small-scale laboratory procedure to determine the self heating tendency of oil-based materials by exposure to elevated temperatures in air in a controlled semi-adiabatic system.1.2 This test method has been developed to address an urgent need to identify oil-based materials that may require labeling for spontaneous heating tendency. Studies based on this test method may allow the development of a practice to identify such oil-based materials.1.3 The values stated in SI units are to be regarded as standard. 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. For safety concerns specific to disposal of solvent-soaked rags, see Appendix X1.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 515元 / 折扣价： 438 元 加购物车

This specification covers composite ribbed steel pipe, precoated and polyethyene lined intended for use for gravity flow sanitary sewers, storm sewers, and other special applications such as water transmission pipe, rehabilitation pipe, slip line pipe, and irrigation pipe. Pipes shall be fabricated in full circular cross-section with helical lock seams and helical ribs projecting outwardly. Specimens cut from production pipe normal to and across the lock seam shall conform to the required values of tensile strength. The pipe shall conform to the required values of nominal inside diameter and sheet thickness. Joint connectors for composite ribbed steel pipe precoated and polyethylene lined shall be specified as soil tight, water-resistant, or watertight.1.1 This specification covers composite ribbed steel pipe, precoated and polyethylene lined intended for use for gravity flow sanitary sewers, storm sewers, and other special applications such as water transmission pipe, rehabilitation pipe, slip line pipe, and irrigation pipe where extra corrosion and abrasion resistance are required. The steel sheet used in the fabrication of the pipe has a polymer coating over a metallic coating of zinc on both sides. In addition, as the pipe is being fabricated, the ribs are filled with polyethylene and then a polyethylene liner is extruded onto the interior surface.1.2 The exterior polymer precoating provides extra protection of the steel against soilside corrosion, in addition to that provided by the metallic coating, and also provides a dielectric barrier for cathodic protection. The interior polymer precoating provides an adhesive layer between the galvanized steel and the polyethylene lining. The applied lining provides internal protection against corrosion, erosion, and abrasion. By filling the rib which has a deltoid shape (smaller at the opening in the pipe wall than at the bottom of the rib), the polyethylene is mechanically connected to the pipe wall and the polyethylene liner is then thermally bonded to the filled rib.1.3 This specification does not include requirements for bedding, backfill, or the relationship between earth cover load and sheet thickness of the pipe. Experience has shown that the successful performance of this product depends upon the proper selection of sheet thickness, type of bedding and backfill, controlled manufacture in the plant, and care in the installation. The installation procedure is described in Practice A798/A798M.1.4 This specification is applicable to orders in either inch-pound units as A978, or in SI units as A978M. Inch-pound units and SI units are not necessarily equivalent. SI units are shown in brackets in the text for clarity, but they are the applicable values when the material is ordered to A978M.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.

定价： 0元 / 折扣价： 0 元

1.1 This specification addresses less lethal chemical irritant sprays used by law enforcement, corrections, and other public safety officers.1.2 This specification is limited to duty belt-mounted canisters.1.3 This specification is limited to sprays intended for use on humans.1.4 This specification defines requirements for products containing liquid aerosol Oleoresin Capsicum (OC) spray (that is, pepper spray), Orthochlorobenzalmalononitrile (CS) spray (that is, 2–chlorobenzylidenemalononitrile; CAS #: 2698-41-1), or OC-CS combination spray. The formulation may be delivered as a stream, gel, foam, cone, or vapor.1.5 This specification does not address incendiary devices or “hot gas.”1.6 Products covered by this specification may be flammable or nonflammable.1.7 Products covered by this specification are hazardous substances as defined by 16 CFR 1500.3.1.8 It is intended that the following related practice be used in conjunction with this specification: Practice E3215.1.9 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.1.9.1 For some quantities in Sections 9, 10, and 11, only SI units are used to be consistent with industry practice.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.

定价： 590元 / 折扣价： 502 元 加购物车

This guide is intended for use in any laboratory utilizing PCR or RT-PCR to amplify and detect nucleic acid sequences of mycobacteria from a biological preparation and to identify the species of origin.The criteria used for the identification and evaluation of the amplification reactions should be administered by an individual trained in the use of molecular biological and microbiological techniques associated with PCR and MTB.1.1 This guide covers basic considerations, criteria, principles and recommendations that should be helpful when developing, utilizing, or assessing PCR-specific protocols for the amplification and detection or identification of mycobacterial nucleic acids. This guide is not a specific protocol for the detection of specific mycobacteria. It is intended to provide information that will assist the user in obtaining high quality and reliable data. The guide is closely related to and should be used concurrently with the general PCR Guide E 1873.1.2 This guide has been developed for use in any molecular biology or biotechnology laboratory. It may be useful for the detection of mycobacteria in clinical, diagnostic laboratories.1.3 This guide does not cover details of the various methods such as gel electrophoresis that can be utilized to help identify PCR-amplified mycobacterial nucleic acid sequences, and it does not cover details of instrument calibration.1.4 This guide does not cover specific variations of the basic PCR or RT-PCR technology (for example, quantitative PCR, multiplex PCR and in situ PCR), and it does not cover details of instrument calibration.1.5 Warning-Laboratory work involving certain clinical specimens and microorganisms can be hazardous to personnel. Precaution: Biosafety Level 2 facilities are recommended for potentially hazardous work, and Biosafety Level 3 facilities are required for propagating and manipulating Mycobacteria tuberculosis cultures (). Safety guidelines should be adhered to according to NCCLS M29-T2, I17-P and other recommendations ().

定价： 0元 / 折扣价： 0 元

This specification covers polyvinyl chloride and other conforming organic polymer-coated steel chain-link fabric, coated before weaving. Fabric produced from three classes of wire coatings are covered as follows: Class I consists of polymer coatings extruded over zinc-coated, aluminum-coated, or zinc-5 % aluminum-mischmetal alloy-coated, or zinc-5 % aluminum-mischmetal alloy-coated steel wire; Class 2a consists of polymer coating extruded and adhered to zinc-coated, aluminum-coated, or zinc-5 % aluminum-mischmetal alloy-coated steel wire; Class 2b consists of polymer coating fused and adhered to zinc-coated, aluminum-coated, or zinc-5 % aluminum-mischmetal alloy-coated steel wire. Materials shall be tested and the individual grades shall conform to material, weave, mesh size, diamond count, wire size, fabric height, selvage, breaking strength, weight of Zinc, Aluminum, or Zinc-5 % Aluminum-Mischmetal Alloy Coatings, polymer coating thickness, polymer-coated wire, and roll length.1.1 This specification covers polyvinyl chloride and other conforming organic polymer-coated steel chain-link fabric, coated before weaving. Polyvinyl chloride, polyolefin, and other organic polymer coating hereinafter will be designated as polymer coating.1.2 Fabric produced from three classes of wire coatings are covered as follows:1.2.1 Class I consists of polymer coatings extruded over zinc-coated, aluminum-coated, or zinc-5 % aluminum-mischmetal alloy-coated, or zinc-5 % aluminum-mischmetal alloy-coated steel wire.1.2.2 Class 2a consists of polymer coating extruded and adhered to zinc-coated, aluminum-coated, or zinc-5 % aluminum-mischmetal alloy-coated steel wire.1.2.3 Class 2b consists of polymer coating fused and adhered to zinc-coated, aluminum-coated, or zinc-5 % aluminum-mischmetal alloy-coated steel wire.1.3 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are provided 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.

定价： 590元 / 折扣价： 502 元 加购物车

4.1 Precision statements for calculated values can be developed using this approach. Users can also evaluate how an individual test method’s precision influences the variability of calculated values.4.2 The standard deviation of a calculated value that is the sum, difference, product, or quotient of two or more test method results, each with their own precision statement, can be calculated so long as the individual variables (that is, test results) are independent and the standard deviations are small relative to their mean values. These restrictions are usually met in ASTM methods. In those cases where these restrictions are not met, other methods can be used. Only cases complying with the restrictions are covered in this standard.1.1 Material and mixture properties such as air voids and voids in mineral aggregates (VMA) are calculated from two or three test results, combined in simple mathematical relationships. The standard deviation equations for these calculated values can be developed using a mathematical process called “propagation of errors” (also called “propagation of uncertainty”). This practice includes uncertainty equations for four forms or material and mixture equations: when two test results are (1) added or subtracted, (2) multiplied together, (3) one divided by the other, and (4) two test results divided by a third.1.2 This approach to calculating standard deviation equations is only valid when the distributions of the test results from the two standards are independent (that is, not correlated).1.3 The accuracy of a calculated standard deviation is dependent on the accuracy of the standard deviations used for the individual test result methods.1.4 Values for the mean and standard deviation for each test method are needed to determine the standard deviation for a calculated value.1.5 Examples of how to use these equations are shown in Appendix X1.1.6 A brief explanation of how standard deviation equations are derived for more complicated material and mixture equations is also included.1.7 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.1.8 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.1.9 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.

定价： 515元 / 折扣价： 438 元 加购物车

This specification covers the standard for wrought copper-alloy bearing plate and bearing sheets intended for use in bridges and other structures. The plates and sheets are also proposed for use as fixed or expansion bearings where motion is slow and intermittent. Specimens shall be manufactured by hot working, cold working, and annealing. Specimens shall adhere to mechanical properties such as tensile strength, yield strength, and elongation. The plates and sheets shall be subjected to tensile, hardness, and compression tests. The specimens shall also undergo chemical analysis. When the specimens fail to conform to the specification, a retest shall be permitted.1.1 This specification establishes the requirements for wrought copper-alloy bearing plate and bearing sheets for application in bridges and other structures. Specifically, the plates and sheets are to be used for fixed or expansion bearings where the motion is slow and intermittent with pressures not exceeding 3 ksi (20 MPa).1.2 Units—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.1.2.1 Exception—Values given in inch-pound units are the standard except for grain size, which is stated in SI units.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.

定价： 590元 / 折扣价： 502 元 加购物车

This specification covers a group of common requirements that, unless otherwise specified in an individual specification, shall apply to ferroalloys and other alloying materials. The chemical analysis method shall be agreed upon by the purchaser and supplier. Unless otherwise specified, the material shall be sampled for determination of chemical composition and size.1.1 This specification covers a group of common requirements that, unless otherwise specified in an individual specification, shall apply to ferroalloys and other alloying materials under each of the following ASTM specifications:Title of Specification ASTM DesignationFerromanganese A99Ferrosilicon A100Ferrochromium A101Ferrovanadium A102Ferromolybdenum A132Molybdenum Oxide Products A146Ferroboron A323Ferrotitanium A324Chromium Metal A481Ferrochrome-Silicon A482/A482MSilicomanganese A483/A483MCalcium-Silicon Alloys A495Ferrocolumbium A550Electrolytic Manganese Metal A601/A601MNickel Oxide Sinter A636Ferromanganese Silicon A701/A701MTitanium Scrap for Use in Deoxidation and Alloying of Steel A845Aluminum Scrap for Use in Deoxidation and Alloying of Steel A846Silicon Metal A9221.2 This specification also covers a group of supplementary requirements which may be applied to the above specifications as indicated therein. These are provided for use when additional testing or inspection is desired and apply only when specified individually by the purchaser in the order.1.3 In case of conflict between the requirements of the individual specification and this general specification, the former shall prevail.1.4 Units—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.1.4.1 This specification is expressed in both inch-pound units and in SI units (within the text, the SI units are shown in brackets); however, unless the purchase order or contract specifies the applicable M specification designation (SI units), the inch-pound units shall apply.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.

定价： 515元 / 折扣价： 438 元 加购物车

1.1 This practice establishes the certification requirements for less lethal aerosol devices used by law enforcement, corrections officers, and other public safety officers.1.1.1 This practice is intended to be used by certification bodies and by purchasers and suppliers in the procurement of less lethal aerosol devices that meet Specification E3187/E3187M.1.1.2 The performance, testing, labeling, documentation, and reporting requirements for certification are specified in Specification E3187/E3187M.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.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.

定价： 590元 / 折扣价： 502 元 加购物车

1.1 This test method covers a procedure for the nondestructive measurement of the thickness of transparent anodic coatings on aluminum articles by means of the light-section microscope. This method may also be used to measure the thickness of any transparent coating on an opaque reflective surface.1.2 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety problems 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.

定价： 0元 / 折扣价： 0 元

5.1 Test Method D2968 for the determination of med and kemp fibers by microprojection may be used for the acceptance testing of commercial shipments of wool and other animal fibers, but caution is advised since only a few types of animal fibers have been subjected to interlaboratory tests to ascertain the precision of tests for med and kemp fibers by this test method. Comparative tests as directed in 5.1.1 may be advisable.5.1.1 In case of a dispute arising from differences in reported test results when using Test Method D2968 for acceptance testing of commercial shipments, the purchaser and the supplier should conduct comparative tests to determine if there is a statistical bias between their laboratories. Competent statistical assistance is recommended for the investigation of bias. As a minimum, the two parties should take a group of test specimens which are as homogeneous as possible and which are from a lot of material of the type in question. The test specimens should then be randomly assigned in equal numbers to each laboratory for testing. The average results from the two laboratories should be compared using Student's t-test for unpaired data and an acceptable probability level chosen by the two parties before testing is begun. If a bias is found, either its cause must be found and corrected, or the purchaser and the supplier must agree to interpret future test results in view of the known bias.5.2 Knowledge of the incidence of med fibers and kemp fibers in wool and other animal fibers is of importance to manufacturers of woven or knitted fabrics because of the apparent dye resistance and light reflectance qualities of these fibers. This is not to imply that all kemp fibers will resist dye and all med fibers will accept dye normally. In practice, a proportion of kemp fibers will appear normal after dyeing and a proportion of med fibers will appear chalky white after dyeing. From the perspective of visual and aesthetic problems, medullated fibers having an abnormally large diameter and a high degree of medullation are probably the worst kind.1.1 This test method covers the determination by microprojection of the percentage of medullated fibers (med and kemp fibers) in wool or other animal fibers such as mohair, cashmere, alpaca, or camel's hair in their various forms.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.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.

定价： 515元 / 折扣价： 438 元 加购物车