4.1 This test method is used to determine the equilibrium rate of wear and coefficient of friction of materials in rubbing contact under useful operating conditions, that is, combinations of pressure and velocity that fall below the PV (pressure × velocity) limit of the test material. The user of this test method should determine to his own satisfaction whether the results of this test procedure correlate with field performance or other bench test machines. If the test conditions are changed, the wear rates may change and the relative value of one material with respect to another may also change.4.2 Test conditions may be selected from Table 1.(A) For many applications a wear rate exceeding 1.0 × 10−5  in./h (2.5 × 10−7 m/h) is considered excessive. Typical wear rates for some commonly used materials at different PV levels are:  Acetal homopolymer at PV1: 5 × 10−6 in./h to 1 × 10−5 in./h (1.3 × 10−7 m/h to 2.5 × 10−7 m/h)  Acetal homopolymer at PV2: 1 × 10−5 in./h to 3 × 10−5 in./h (2.5 × 10−7 m/h to 7.5 × 10−7 m/h)  22 % PTFE-filled acetal homopolymer at PV2: 3 × 10−6 in./h to 6 × 10−6 in./h (7.5 × 10−8 m/h to 1.5 × 10−7 m/h)  Polyamide (Type 6-6) at PV2: 1 × 10−5 in./h to 5 × 10−5 in./h (2.5 × 10−7 m/h to 1.3 × 10−6 m/h)  15 % graphite filled polyimide restin at PV3: 1 × 10−5 in./h to 2 × 10−5 in./h (2.5 × 10−7 m/h to 5 × 10−7 m/h)4.3 The precision of wear measurement is relatively independent of test duration or amount of wear, but the precision of wear rate (calculation) improves with test duration and amount of wear. It is generally believed that useful wear rate precision requires the selection of a test duration sufficient to produce 0.1 mm (0.004 in.) of wear. Test durations will often be in the 50 h to 4000 h range.1.1 This test method covers the determination of wear rate and coefficient of friction for self-lubricated materials in rubbing contact by a testing machine2 that utilizes a thrust washer specimen configuration.NOTE 1: This machine may also be used to measure coefficient of friction.1.2 The values in SI units are to be regarded as the standard. In cases where materials, products, or equipment are available only in inch-pound units, SI values in parentheses are for information only.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 different procedures and methods are designed to be used to produce survival data after microorganisms are exposed to antimicrobial agents in order to calculate values that can be used to analyze and rationalize the effectiveness of antimicrobial agents when tested using other, often applied test methods.5.2 The data from these test procedures may be used in the selection and design of other tests of effectiveness of antimicrobial agents, some of which may be required by regulatory agencies to establish specific claims. Basic kinetic information about killing rate often serves as the initial information on which a testing program can be built.1.1 This guide covers the methods for determining the death rate kinetics expressed as D-values. These values can be derived from the construction of a kill curve (or survivor curve) or by using other procedures for determining the number of survivors after exposure to antimicrobial chemicals or formulations. Options for calculations will be presented as well as the method for calculation of a concentration coefficient.1.1.1 The test methods are designed to evaluate antimicrobial agents in formulations to define a survivor curve and to subsequently calculate a D-value. The tests are designed to produce data and calculate values that provide basic information of the rate-of-kill of antimicrobial formulations tested against single, selected microorganisms. In addition, calculated D-values from survivor curves from exposure at different dilutions of antimicrobial can be used to show the effect of dilution by calculation of the concentration exponent, η (2). D-value determination assumes the ideal of first-order killing reactions that are reflected in a straight-line reduction in count where a count-versus-time plot is done. The goal here is not to determine the time at which no survivors are found, but to determine a standard value that can be used in processing and exposure determinations or used to estimate dilutions.1.1.2 As an example of potential use of kill curve data, the published FDA, OTC Tentative Final Monograph for Health-Care Antiseptic Drug Products, Proposed Rule, June 17, 1994 has suggested the testing of topically applied antimicrobial products using survival curve (or kill curve) calculations. The methods described in this guide are applicable to these products, but adjustments such as the use of antifoaming agents when the reaction mixture is stirred may be necessary to counteract the presence of detergents in many formulations. Frequently the sampling for these tests is done after very short intervals of exposure to the formulation, such as 30 and 60 s. This methodology also has been applied to preservative testing of antimicrobial ingredients in more complex cosmetic formulations (5).1.2 The test methods discussed should be performed only by those trained in microbiological techniques.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.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 This test method for testing yarn-to-yarn friction is being used, but is not recommended, for acceptance testing of commercial shipments since between-laboratory precision is known to be poor.5.1.1 In some cases, the purchaser and 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 of commercial shipments. In case of a dispute arising from differences in reported test results when using Test Method D3412/D3412M 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 that are as homogeneous as possible and that 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 the 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 with consideration to the known bias.5.2 This test method is intended for the determination of yarn-to-yarn boundary friction coefficients measured over a specified length of yarn.5.3 The test method is useful for quality control, research, and the characterization of yarn boundary lubricants.NOTE 3: Because the geometry of the yarns is different, Options 1 and 2 should not be expected to give the same numerical values on the same yarns.1.1 This test method covers the measurement of frictional properties for both continuous filament and spun-staple yarns under boundary friction conditions.1.2 This test method has been used with yarns having linear densities ranging from 1.5 to 400 tex, but may be used with yarns outside these ranges [15 to 3600 denier].NOTE 1: For coefficient of friction, yarn to metal, see Test Method D3108/D3108M.1.3 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.1.4 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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3.1 Stress-optical coefficients are used in the determination of stress in glass. They are particularly useful in determining the magnitude of thermal residual stresses for annealing or pre-stressing (tempering) glass. As such, they can be important in specification acceptance.1.1 This test method covers procedures for determining the stress-optical coefficient of glass, which is used in photoelastic analyses. In Procedure A the optical retardation is determined for a glass fiber subjected to uniaxial tension. In Procedure B the optical retardation is determined for a beam of glass of rectangular cross section when subjected to four-point bending. In Procedure C, the optical retardation is measured for a beam of glass of rectangular cross-section when subjected to uniaxial compression.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.

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The horizontal dynamometer pull meter and heel assemblies are designed to determine the static coefficient of friction of tile and like materials.The measurement made by this apparatus is believed to be one important factor relative to slip resistance. Other factors can affect slip resistance, such as the degree of wear on the shoe and flooring material; presence of foreign material, such as water, oil, and dirt; the length of the human stride at the time of slip; type of floor finish; and the physical and mental condition of humans. Therefore, this test method should be used for the purpose of developing a property of the flooring surface under laboratory conditions, and should not be used to determine slip resistance under field conditions unless those conditions are fully described.Because many variables may enter into the evaluation of slip resistance of a particular surface, this test method is designed to evaluate these surfaces under both laboratory and actual site installation conditions.The static coefficient of friction is determined under both wet and dry conditions with Neolite heel assemblies over both unprepared and prepared (cleaned) test surfaces.1.1 This test method covers the measurement of static coefficient of friction of ceramic tile or other surfaces under both wet and dry conditions while utilizing Neolite heel assemblies. This test method can be used in the laboratory or in the field.1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

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5.1 Test Method D3108 for the determination of kinetic friction between yarn and solid materials may be used for the acceptance testing of commercial shipments of yarn, but caution is advised since between laboratory precision is known to be poor. Comparative tests as directed in 5.1.1 may be advisable.5.1.1 If there are differences or practical significance between reported test results for two laboratories (or more), comparative tests should be performed to determine if there is a statistical bias between them, using competent statistical assistance. As a minimum, test samples that are as homogenous as possible, drawn from the material from which the disparate test results were obtained, and randomly assigned in equal numbers to each laboratory for testing. The test results from the two laboratories should be compared using a statistical test for unpaired data, at a probability level chosen prior to the testing series. If a bias is found, either its cause must be found and corrected, or future test results for that material must be adjusted in consideration of the known bias.5.2 The frictional properties of textile yarns and of machinery components such as yarn guides are of general interest and have many applications. Because the frictional properties of yarns will affect the performance and life of yarn guides, sewing and knitting needles, and other contact surfaces, the modifying effects of surface finishes and lubricants are of special interest. Frictional properties also affect the quality and performance properties of yarns and subsequently of products made from them. As a consequence, frictional properties are of interest in research, control, and product design.5.3 It is stressed that there is no coefficient of friction for a single body such as a yarn or a surface. A coefficient of friction measures the interaction between two bodies or elements such as a yarn running over a surface.5.4 Although this method lays down standardized conditions of test, nonstandard conditions may be used for research or diagnosis but should be reported as such.5.5 This method covers determination of the mean friction over a specified length of yarn.5.6 Additional information has been reported in the literature.3,4,51.1 This test method covers the measurement of the kinetic frictional properties of a moving yarn in contact with a solid material.NOTE 1: For determining yarn-to-yarn friction, refer to Test Method D3412.1.2 This test method specifies a relative speed of 100 m/min. The test method may be used at other speeds, although with a possible change in precision and coefficient of friction.1.3 This test method covers the measurement of the coefficient of kinetic friction between yarn and solid surface or surfaces of constant radius in the contact area. If a yarn of uniform value is used, comparisons of frictional properties of different solid materials can be made with relation to that yarn. If a given solid material is used, comparisons of frictional properties of different yarns, or yarns with different finishes, can be made with relation to that particular solid material.1.4 This test method specifically recommends wrap angles of 1.57, 3.14 and 6.28 radian (90, 180 and 360°), but other wrap angles may be used, again with a possible change in precision and level. The angle of wrap should not be so great, especially for yarns having high coefficients of friction, that it causes the output tension to exceed the yield value for the yarn being tested. Also, in every case the angle of wrap should not be less than 1.57 rad (90°).1.5 This test method has been applied to yarns having linear densities ranging between 1.5 and 400 tex [14 and 3600 denier] and having coefficients of friction ranging between 0.1 and 1.0 but may also be used with yarns outside these ranges of linear densities and coefficients of friction.1.6 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.1.7 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.Specific precautionary statements are given in Section 7.1.8 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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5.1 Guide G115 lists a number of ASTM International standards that use the inclined plane test rig to measure the static coefficient of specific tribosystems. This guide applies to any material couple that can be made into test specimens; one being in the form of a rider and the other a plane that can be angled to produce motion of the rider on the plane. Footwear on walkway surfaces is an example of a very important application. Flooring surfaces that are slippery to various types of footwear can produce accidents and testing should be done on candidate flooring surfaces and candidate shoe soles and heels to quantify their relative slip resistance. This guide shows how an inclined plane can be used to make such a comparison.5.2 The inclined plane method is also very useful in machine design in which parts of components shall slide unassisted down chutes and the like. An inclined plane test can be used to determine the chute angle that is needed to allow motion on all parts that are placed on the chute. The applications are numerous.1.1 This guide is intended to standardize the use of an inclined plane testing device to measure the static (breakaway) coefficient of friction between two bodies. One body is in the form of a small “rider” (few centimeters) and the other a rectangular flat plane (50 mm to 75 mm by 400 mm). The rider is placed on the plane and the plane is inclined at an angle to produce motion of the rider. The tangent of the angle at which macroscopic motion of the rider initiates on the angled plane is the breakaway or static coefficient of friction for that sliding couple.1.2 Units—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 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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The coefficient of retroreflected luminance, RL, is the property of a pavement marking system that provides a measure of the retroreflective efficiency of the marking and depends on factors such as the materials used, age, and wear pattern. These conditions shall be observed and noted by the user.Under identical conditions of headlight illumination and driver's viewing, larger values of RL correspond to higher levels of visibility at corresponding geometry.The pavement marking's measured retroreflective efficiency in conditions of continuous wetting may be used to characterize the properties of the marking on the road as water is continuously falling on it. The retroreflective efficiency of the marking in conditions of continuous wetting may be different than in dry, wet or damp conditions.This test method may produce measurements of RL-Rain for pavement marking systems that do not correlate to nighttime visibility distance during typical rain events. The rainfall intensity simulated by this test method is significantly greater than most ordinary or even heavy rainfall events. As a result, the test specimen, unless it has vertical features exceeding3 mm, becomes flooded. Optics with an index of refraction less than 2.0 are practically ineffective when immersed in water. Thus, the test method is of limited applicability for assessing the wet retroreflective properties of pavement marking systems having vertical features less than 3 mm or optics having an index of refraction less than 2.0.Retroreflectivity of pavement (road) markings degrades with traffic wear and requires periodic measurement to ensure that sufficient line visibility is provided to drivers.Newly installed pavement markings may have a natural surface tension or release agents which prevent wetting of the marking by rain/water. This phenomenon produces unreliable and unrepeatable results when measuring retroreflective efficiency under wet conditions. This non-wetting phenomenon is generally eliminated after one month of wear and weathering on the road. A wetting agent can be used to estimate the RL-Rain properties of new markings (see 5.4).Roadway characteristics such as longitudinal slope, cross slope and pavement porosity will impact the results of this test method.1.1 This test method covers a measurement of the wet retroreflective (RL-Rain) properties of horizontal pavement marking materials, such as traffic stripes and road surface symbols.1.2 This method of measuring wet retroreflective properties (RL) of pavement markings utilizes a method of continuously wetting the marking during measurement (see Fig. 1).Note 1—Test Method E 2177 may be used to describe the retroreflective properties of pavement markings in conditions of wetness after a period of rain.1.3 This test method is most suitable for laboratory use under controlled conditions, but may also be used for field measurements when the necessary controls and precautions are followed.1.4 This test method specifies the use of reflectometers that can measure pavement markings per Test Method E 1710. The entrance and observation angles required of the retroreflectometer in this test method are commonly referred to as “30 meter geometry.”1.5 This test method has been shown to produce reasonable results for pavement marking systems with optics having an index of refraction greater than 2.0 and structured markings having vertical structures greater than or equal to 3 mm. Users should exercise caution when using this test method for pavement marking systems with optics having an index of refraction less than 2.0 or markings having vertical structures less than 3 mm.1.6 Results obtained using this test method should not be the sole basis for specifying and assessing the wet retroreflective effectiveness of pavement marking systems. Users should complement the results of this test method with other evaluation results, such as nighttime visual inspections.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 and health practices and determine the applicability of regulatory limitations prior to use.Note 2—An alternative test method designed to better represent the retroreflective efficiency of pavement marking systems under typical rain events is under development.FIG. 1 Illustration of Measurement

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4.1 The nighttime performance of pavement markings is determined by the coefficient of retroreflected luminance, RL, be it dry or wet, and depends on the materials used, age, and wear pattern. These conditions shall be observed and noted by the user.4.2 Under the same conditions of headlight illumination and driver’s viewing, larger values of RL correspond to higher levels of visual performance at corresponding geometry.4.3 The pavement marking’s measured performance in the condition of wet recovery is used to characterize the performance of the marking on the road when wet.4.4 Newly installed pavement markings may have a natural surface tension or release agents that prevent wetting of the product by water. The water will tend to “bead up” on the marking. This “non wetting” condition is usually short lived. Pavement markings that have been on the road for one month prior to testing usually do not exhibit this non-wetting phenomenon. (Warning—This phenomenon produces an interference when assessing the wet characteristics of a pavement marking. Attempts to measure markings with this surface “non-wetting” or “beading” of the water may give higher values.)4.5 The retroreflectivity, RL, of pavement (road) markings degrades with traffic wear and requires periodic measurement to ensure that sufficient line visibility is provided to drivers.4.6 For a given viewing distance, measurements of RL made with a retroreflectometer having a geometry corresponding to that viewing distance are a good indicator of the visual ranking of the material measured.4.7 As specified by Test Method E1710, the measurement geometry of the instrument is based on a viewing distance of 30 m, an eye height of 1.2 m and a headlight mounting height of 0.65 m (see Appendix X1).4.8 It shall be the responsibility of the user to employ an instrument having the specified observation and entrance angles.1.1 This test method covers the measurement of the wet retroreflective (RL) properties of horizontal pavement marking materials, such as traffic stripes and road surface symbols, using a portable retroreflectometer that can be placed on or before the road marking to measure the retroreflection at the prescribed geometry.1.2 This method of measuring the wet retroreflective properties (RL) of pavement markings measures the wet retroreflectivity in a condition of wet recovery (see Fig. 1).FIG. 1 Illustration of Measurement1.2.1 This test condition typically exists (1) after a rainfall has ended and the pavement markings are still wet or (2) as the markings are wet from dew or humidity.1.3 Retroreflective performance obtained with this test in condition of wet recovery does not necessarily relate to how markings perform in conditions of rain, that is, as markings are being rained upon. Test Method E2832 defines a method to measure the performance of pavement markings in conditions of simulated rain.1.4 This test method specifies the use of portable reflectometers that can measure pavement markings in accordance with Test Method E1710.2 The entrance and observation angles required of the retroreflectometer in this test method are commonly referred to as “30 meter geometry.”21.5 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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5.1 This test method is applicable to cementitious mixtures that have not been exposed to external chloride ions, other than the negligible quantity of chloride ion exposure from sample preparation using potable water, prior to the test.5.2 The calculation procedure described in this test method is applicable only to laboratory test specimens exposed to a sodium chloride solution as described in this test method. This calculation procedure is not applicable to specimens exposed to chloride ions during cyclic wetting and drying.NOTE 1: The diffusion of ionic species in concrete occurs within the fluid-filled pores, cracks and void spaces. The concentration and valence of other ionic species in the pore fluid also influence the rate of chloride diffusion, and therefore, the apparent diffusion coefficient as determined by this test procedure.5.3 In most cases, the value of the apparent chloride diffusion coefficient for cementitious mixtures changes over time (see Note 2). Therefore, apparent diffusion coefficients obtained at early ages may not be representative of performance in service.NOTE 2: The rate of change of the apparent diffusion coefficient for cementitious mixtures containing pozzolans or blast-furnace slag is typically different than that for mixtures containing only portland cement.5.4 The apparent chloride diffusion coefficient is used in Fick's second law of diffusion to estimate chloride penetration into cementitious mixtures that are in a saturated condition.5.5 The apparent chloride diffusion coefficient is commonly used in chloride ingress models based on Fick's second law of diffusion. The apparent diffusion coefficient determined by this method includes bound chloride, so proper use of the apparent chloride diffusion coefficient to predict chloride ingress requires consideration of chloride binding.5.6 The resistance to chloride penetration is affected by such factors as the environment, finishing, mixture composition, workmanship, curing, and age.1.1 This test method covers the laboratory determination of the apparent chloride diffusion coefficient for hardened cementitious mixtures.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 Pavement surfaces have different traction characteristics, depending on many factors. Surface texture, binder content, usage, environmental exposure, and surface conditions (that is, wet, dry) are some of the factors.5.2 The measured values represent peak braking coefficients for tires of the general type in operation on passenger vehicles, obtained with a towed test trailer on a prescribed road surface, under user-defined surface conditions. Such surface conditions may include the water depth used to wet the road surface and the type of water application method. Variations in these conditions may influence the test results.1.1 This test method covers the measurement of peak braking coefficient (PBC) of paved surfaces using a standard reference test tire (SRTT) as described in Specification E1136 or F2493 that represents current technology passenger car radial tires. General test procedures and limitations are presented for determining peak braking coefficient independent of surface conditions. Actual surface test conditions are determined and controlled by the user at the time of test. Test and surface condition documentation procedures and details are specified. This measurement quantifies the peak braking coefficient at the time of test, and does not necessarily represent a maximum or fixed value.1.2 There are many specifications published that refer to the ASTM E1337 PBC Standard assuming the E1136 SRTT in determining peak brake coefficient. Correlation equations for converting data collected using an F2493 SRTT to the older E1136 specification, and converting an older E1136 specification for use with F2493 data, are included in 12.4.1.3 This test method utilizes a measurement representing the peak braking force on a braked test tire passing over a road surface. This test is conducted with a tire under a nominal vertical load at a constant speed while its major plane is parallel to its direction of motion and perpendicular to the pavement.1.4 The measured peak braking coefficient obtained with the equipment and procedures stated herein may not necessarily agree or correlate directly with those obtained by other surface coefficient measuring methods.1.5 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.1.6 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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5.1 The coefficient of linear thermal expansion, α, between temperatures T1 and T2 for a specimen whose length is L0 at the reference temperature, is given by the following equation:where L1 and L2 are the specimen lengths at temperatures T1 and T2, respectively. α is, therefore, obtained by dividing the linear expansion per unit length by the change in temperature.5.2 The nature of most plastics and the construction of the dilatometer make −30 to +30°C (−22°F to +86°F) a convenient temperature range for linear thermal expansion measurements of plastics. This range covers the temperatures in which plastics are most commonly used. Where testing outside of this temperature range or when linear thermal expansion characteristics of a particular plastic are not known through this temperature range, particular attention shall be paid to the factors mentioned in 1.2.NOTE 2: In such cases, special preliminary investigations by thermo-mechanical analysis, such as that prescribed in Practice D4065 for the location of transition temperatures, may be required to avoid excessive error. Other ways of locating phase changes or transition temperatures using the dilatometer itself may be employed to cover the range of temperatures in question by using smaller steps than 30°C (86°F) or by observing the rate of expansion during a steady rise in temperature of the specimen. Once such a transition point has been located, a separate coefficient of expansion for a temperature range below and above the transition point shall be determined. For specification and comparison purposes, the range from −30°C to +30°C (−22°F to +86°F) (provided it is known that no transition exists in this range) shall be used.1.1 This test method covers determination of the coefficient of linear thermal expansion for plastic materials having coefficients of expansion greater than 1 µm/(m.°C) by use of a vitreous silica dilatometer. At the test temperatures and under the stresses imposed, the plastic materials shall have a negligible creep or elastic strain rate or both, insofar as these properties would significantly affect the accuracy of the measurements.1.1.1 Test Method E228 shall be used for temperatures other than −30°C to 30°C.1.1.2 This test method shall not be used for measurements on materials having a very low coefficient of expansion (less than 1 µm/(m.°C). For materials having very low coefficient of expansion, interferometer or capacitance techniques are recommended.1.1.3 Alternative technique commonly used for measuring this property is thermomechanical analysis as described in Test Method E831, which permits measurement of this property over a scanned temperature range.1.2 The thermal expansion of a plastic is composed of a reversible component on which are superimposed changes in length due to changes in moisture content, curing, loss of plasticizer or solvents, release of stresses, phase changes and other factors. This test method is intended for determining the coefficient of linear thermal expansion under the exclusion of these factors as far as possible. In general, it will not be possible to exclude the effect of these factors completely. For this reason, the test method can be expected to give only an approximation to the true thermal expansion.1.3 The values stated in SI units are to be regarded as standard. The values 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 and health practices and determine the applicability of regulatory limitations prior to use.NOTE 1: There is no known ISO equivalent to this standard.

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5.1 The ball coefficient of restitution is a ball dynamic property of relative velocity change caused by impact with a rigid wall.5.2 This test method is suitable for obtaining data in research and development, quality control, and classifying balls by liveliness.5.3 Sports associations can use coefficient of restitution standards in specifications for official baseballs and softballs.5.4 This same test procedure can be utilized at impact speeds other then that prescribed in this procedure and so noted in any reported test results.1.1 This procedure is intended to standardize a method of measuring the coefficient of restitution (COR) of baseballs and softballs.1.2 This procedure is established to provide a single, repeatable, and uniform test method.1.3 This procedure is for a ball that is intended for use in the game of baseball or softball.1.4 The test method is based on ball speed measurements before and after impact with either of two test surfaces: wood or metal.1.5 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.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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