The use of GaAs for semiconductor devices requires a consistent atomic lattice structure. However, lattice or crystal line defects of various types and quantities are always present, and rarely homogeneously distributed. It is important to determine the mean value and the spatial distribution of the etch pit density.1.1 This test method is used to determine whether an ingot or wafer of gallium arsenide is monocrystalline and, if so, to measure the etch pit density and to judge the nature of crystal imperfections. To the extent possible, it follows the corresponding test method for silicon, Test Method F 47. Test Method F 47 also presents the definition of many crystallographic terms, applicable to this test method. 1.2 This procedure is suitable for gallium arsenide crystals with etch pit densities between 0 and 200 000/cm2. 1.3 Gallium arsenide, either doped or undoped, and with various electrical properties, may be evaluated by this test method. The front surface normal direction of the sample must be parallel to the <001> within ± 5° and must be suitably prepared by polishing or etching, or both. Unremoved processing damage may lead to etch pits, obscuring the quality of the bulk crystal. 1.4 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and to determine the applicability of regulatory limitations prior to use. Specific hazard statements are given in Section 8.

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

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5.1 The purpose of the alternating current field measurement method is to evaluate threads for surface breaking discontinuities such as fatigue cracks running along the thread root. The examination results may then be used to determine the fate of the test piece. This may involve re-examination by an alternative technique, immediate scrapping of the test piece, or reworking to remove discontinuities (beyond the scope of this practice). This practice is not intended for the examination of threads for non-surface breaking discontinuities.1.1 This practice describes procedures to be followed during alternating current field measurement examination of drillstring threads on tubulars used for oil and gas exploration and production for detection and, if required, sizing of service-induced surface breaking discontinuities transverse to the pipe.1.2 This practice is intended for use on threads in any metallic material.1.3 This practice does not establish acceptance criteria. Typical industry practice is to reject these connections on detection of a confirmed crack.1.4 While the alternating current field measurement technique is capable of detecting discontinuities in these connections, supplemental surface NDT methods such as magnetic particle testing for ferrous metals and penetrant testing for non-ferrous metals may detect additional discontinuities.1.5 Units—The values stated in either inch-pound units or SI units are to be regarded separately as standard. The values stated in each system might not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from both systems may result in nonconformance with the 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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The knowledge of vehicle stopping distance or deceleration serves as an additional tool in characterizing the pavement surface skid resistance. When used in conjunctionwith other physical and chemical tests, the skid resistance values derived from these test methods may determine the suitability and adequacy of paving materials or finishing techniques. Improvements in pavement maintenance practices and schedules may result from use of these test methods.The stopping distance or deceleration values measured by these two test methods with the equipment and procedures stated herein do not necessarily agree or correlate directly with other methods of skid-resistance measurements. These test methods are suitable where direct comparison between pavement surfaces are to be made within the same test program.1.1 These test methods cover the measurement of skid resistance on paved surfaces with a passenger vehicle equipped with specified full-scale vehicle tires and using the diagonal braking mode. These test methods include the following:1.1.1 Full-Stop Method This represents the nonsteady-state skid resistance on two diagonally locked wheels, as the vehicle decelerates over a wetted pavement surface under specified limits of static wheel load and from a desired speed. The vehicle shall remain essentially parallel to its original direction of motion.1.1.2 Pulse-Braking MethodThe deceleration resulting from momentary diagonal wheel lockup (pulse braking) is measured. The vehicle decelerates over a wetted pavement surface under specified limits of static wheel load and at a desired speed. The vehicle shall remain essentially parallel to its original direction of motion.1.2 The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system are not exact equivalents: therefore, each system must be used independently of the other. Combining values from the two systems may result in nonconformance with the specification.

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5.1 The comparative method of measurement of thermal conductivity is especially useful for engineering materials including ceramics, polymers, metals and alloys, refractories, carbons, and graphites including combinations and other composite forms of each.5.2 Proper design of a guarded-longitudinal system is difficult and it is not practical in a method of this type to try to establish details of construction and procedures to cover all contingencies that might offer difficulties to a person without technical knowledge concerning theory of heat flow, temperature measurements, and general testing practices. Standardization of this test method is not intended to restrict in any way the future development by research workers of new or methods or improved procedures. However, new or improved techniques must be thoroughly tested. Requirements for qualifying an apparatus are outlined in Section 10.1.1 This test method describes a steady state technique for the determination of the thermal conductivity, λ, of homogeneous-opaque solids (see Notes 1 and 2). This test method is applicable to materials with effective thermal conductivities in the range 0.2 < λ < 200 W/(m·K) over the temperature range between 90 K and 1300 K. It can be used outside these ranges with decreased accuracy.NOTE 1: For purposes of this technique, a system is homogeneous if the apparent thermal conductivity of the specimen, λA, does not vary with changes of thickness or cross-sectional area by more than ±5 %. For composites or heterogeneous systems consisting of slabs or plates bonded together, the specimen should be more than 20 units wide and 20 units thick, respectively, where a unit is the thickness of the thickest slab or plate, so that diameter or length changes of one-half unit will affect the apparent λA by less than ±5 %. For systems that are non-opaque or partially transparent in the infrared, the combined error due to inhomogeneity and photon transmission should be less than ±5 %. Measurements on highly transparent solids must be accompanied with infrared absorption coefficient information, or the results must be reported as apparent thermal conductivity, λA.NOTE 2: This test method may also be used to evaluate the contact thermal conductance/resistance of materials and composites.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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This test method provides a means of evaluating and comparing development of corrosion at scribe on painted/coated flat test panels after exposure to corrosive environments.1.1 This test method covers the measurement of rust creepage area from a scribe line on painted/coated flat test panels after exposure to corrosive environments. This test method has the advantage of simplicity and ease of use. Expensive equipment is not required, and the results are more accurate than visual evaluation but not as precise as advanced digital imaging. 1.2 This test method uses visual imaging software to determine the area damaged by rust creepage from the scribe. 1.3 The values stated in SI units are to be regarded as the 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 and health practices and determine the applicability of regulatory limitations prior to use.

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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 ().

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3.1 The GESD procedure can be used to simultaneously identify up to a pre-determined number of outliers (r) in a data set, without having to pre-examine the data set and make a priori decisions as to the location and number of potential outliers.3.2 The GESD procedure is robust to masking. Masking describes the phenomenon where the existence of multiple outliers can prevent an outlier identification procedure from declaring any of the observations in a data set to be outliers.3.3 The GESD procedure is automation-friendly, and hence can easily be programmed as automated computer algorithms.1.1 This practice provides a step by step procedure for the application of the Generalized Extreme Studentized Deviate (GESD) Many-Outlier Procedure to simultaneously identify multiple outliers in a data set. (See Bibliography.)1.2 This practice is applicable to a data set comprising observations that is represented on a continuous numerical scale.1.3 This practice is applicable to a data set comprising a minimum of six observations.1.4 This practice is applicable to a data set where the normal (Gaussian) model is reasonably adequate for the distributional representation of the observations in the data set.1.5 The probability of false identification of outliers associated with the decision criteria set by this practice is 0.01.1.6 It is recommended that the execution of this practice be conducted under the guidance of personnel familiar with the statistical principles and assumptions associated with the GESD technique.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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3.1 This practice establishes a multiple person cold water survival/rescue procedure.3.2 All persons who are identified as water rescuers shall meet the requirements of this practice.3.3 This practice is intended to assist government agencies, state, local, or regional organizations; fire departments; and rescue teams and others who are responsible for establishing a minimum performance for personnel who respond to water emergencies.3.4 The majority of the rescuers performing this technique must be wearing personal flotation devices. These devices should conform to standards set by the appropriate national regulatory authority, that is, the U.S. Coast Guard in the United States, and be in good and serviceable condition.3.5 A water rescuer sometimes may be immersed in cold water for prolonged periods of time. They are unable to get to shore or shore is too far away, rescue is not imminent, no boat is available to get into or on top of, and no flotsam is available. The water rescuer needs to assume a defensive posture to conserve heat and increase survival time.1.1 This practice covers the recommended water rescue procedure for performing the huddle position.1.2 This practice is one in a set of self-rescue techniques for the water rescuer.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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3.1 This practice establishes a single person cold water survival/rescue procedure.3.2 All persons who are identified as water rescuers shall meet the requirements of this practice.3.3 This practice is intended to assist government agencies, state, local, or regional organizations; fire departments; and rescue teams and others who are responsible for establishing a minimum performance for personnel who respond to water emergencies.3.4 A rescuer needs to be wearing a personal flotation device to perform this technique. These devices should conform to standards set by the appropriate national regulatory authority, that is, the U.S. Coast Guard in the United States, and be in good and serviceable condition.3.5 A water rescuer sometimes may be immersed in cold water for prolonged periods of time. They are unable to get to shore or shore is too far away, rescue is not imminent, no boat is available to get into or on top of, and no flotsam is available. The water rescuer needs to assume a defensive posture to conserve heat and increase survival time.1.1 This practice covers the recommended water rescue procedure for performing the heat escape lessening posture (HELP) position.1.2 This practice is one in a set of self-rescue techniques for the water rescuer.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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This test method describes the optical emission vacuum spectrometric procedure for examining blast furnace iron (hot metal) containing 4.2 to 5.0 % carbon by the point-to-plane technique. This spectrochemical technique is intended specifically for the analysis of silicon, manganese, phosphorus, titanium, and sulfur in specified concentration ranges in blast furnace iron. Apparatus needed for this procedure shall include sample mold, grinder, supporting electrode, excitation source, spectrometer, and appropriate measuring system. The sample is excited in an inert gas atmosphere by a controlled triggered capacitor discharge using the point-to-plane technique. Using a vacuum spectrometer, the radiant energies of selected analytical lines and an internal standard line are measured by photomultipliers. The output current of each photomultiplier is accumulated and stored during the exposure period as a charge on an associated capacitor, where it appears as a measurable voltage. At the end of the exposure period the voltages corresponding to the analytical lines relative to the voltage for the internal standard line are measured. The measuring system may be calibrated in terms of percent concentration.1.1 This test method describes the spectrochemical procedure for the analysis of blast furnace iron (hot metal) containing 4.2 to 5.0 % carbon for the following elements in the indicated ranges:Elements Concentration Range, %Silicon 0.50 to 2.00Manganese 0.20 to 1.50Phosphorus 0.020 to 0.15Titanium 0.02 to 0.10Sulfur 0.010 to 0.0501.2This 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 CFMEs are used to measure skid resistance on runways, roads, and various other trafficked surfaces. These tests may comprise operational testing, performed to obtain an immediate assessment of skid resistance in current conditions or routine testing in standardized conditions which include the application of a precise amount of water in front of the test tire.5.2 Standard test speeds and nominal water film thicknesses are according to national or international agency standards, the type of CFME, and the test application. Some examples of typical applications are given in Appendix X1.1.1 This test method covers the measurement of the skid resistance of a pavement or other trafficked surface using the continuous reading, fixed-slip technique.1.2 This test method covers braked wheel measurements obtained with less than 100 % slip. It does not cover side force measurements.1.3 This test method provides a record of the skid resistance along the whole length of one track of the test surface and enables averages to be obtained for specified test segments.1.4 This test method is used to measure skid resistance on a wide variety of surfaces in a wide variety of circumstances. Consequently, there are many different designs of continuous reading, fixed-slip measuring equipment (CFME) and as many different test procedures governing their use.1.5 This test method does not attempt to detail these different equipment and procedures but does set out the essential common principles.1.6 CFMEs function by creating and measuring a frictional force between a test tire operating at a selected slip and the test surface. Different types of CFME do not necessarily create the same frictional force between their particular test tire and a common test surface and do not necessarily use the same method to measure this frictional force.1.7 CFME measurements are obtained at a selected steady test speed. This speed may vary according to the application.1.8 The test surface may be contaminated or clean and dry. If it is clean and dry, a measured amount of water is normally deposited on the surface just in front of the test wheel.1.9 The measuring apparatus may be built into a vehicle, built into a trailer that is towed by a vehicle, or built into a device that is manually pushed.1.10 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.1.11 This standard may involve hazardous materials, operations, and equipment. 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. Safety precautionary information is contained in Section 7.1.12 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 is useful for characterizing material microstructure or measuring variations in microstructure that occur because of material processing conditions and thermal, mechanical, or chemical exposure (3). When applied to monolithic or composite ceramics, the procedure should reveal microstructural gradients due to density, porosity, and grain variations. This practice may also be applied to polycrystalline metals to assess variations in grain size, porosity, and multiphase constituents.5.2 This practice is useful for measuring and comparing microstructural variations among different samples of the same material or for sensing and measuring subtle microstructural variations within a given sample.5.3 This practice is useful for mapping variations in the attenuation coefficient and the attenuation spectrum as they pertain to variations in the microstructure and associated properties of monolithic ceramics, ceramic composites and metals.5.4 This practice is useful for establishing a reference database for comparing materials and for calibrating ultrasonic attenuation measurement equipment.5.5 This practice is not recommended for highly attenuating monolithics or composites that are thick, highly porous, or that have rough or highly textured surfaces. For these materials Practice E664/E664M may be appropriate. Guide E1495/E1495M is recommended for assessing attenuation differences among composite plates and laminates that may exhibit, for example, pervasive matrix porosity or matrix crazing in addition to having complex fiber architectures or thermomechanical degradation (3). The proposed ASTM Standard Practice for Measuring Ultrasonic Velocity in Advanced Ceramics (C1331) is recommended for characterizing monolithic ceramics with significant porosity or porosity variations (4).1.1 This practice describes a procedure for measurement of ultrasonic attenuation coefficients for advanced structural ceramic materials. The procedure is based on a broadband buffered piezoelectric probe used in the pulse-echo contact mode and emitting either longitudinal or shear waves. The primary objective of this practice is materials characterization.1.2 The procedure requires coupling an ultrasonic probe to the surface of a plate-like sample and the recovery of successive front surface and back surface echoes (refer to Fig. 3). Power spectra of the echoes are used to calculate the attenuation spectrum (attenuation coefficient as a function of ultrasonic frequency) for the sample material. The transducer bandwidth and spectral response are selected to cover a range of frequencies and corresponding wavelengths that interact with microstructural features of interest in solid test samples.1.3 The purpose of this practice is to establish fundamental procedures for measurement of ultrasonic attenuation coefficients. These measurements should distinguish and quantify microstructural differences among solid samples and therefore help establish a reference database for comparing materials and calibrating ultrasonic attenuation measurement equipment.1.4 This practice applies to monolithic ceramics and also polycrystalline metals. This practice may be applied to whisker reinforced ceramics, particulate toughened ceramics, and ceramic composites provided that similar constraints on sample size, shape, and finish are met as described herein for monolithic ceramics.1.5 This practice sets forth the constraints on sample size, shape, and finish that will assure valid attenuation coefficient measurements. This practice also describes the instrumentat- ion, methods, and data processing procedures for accomplishing the measurements.1.6 This practice is not recommended for highly attenuating materials such as very thick, very porous, rough-surfaced monolithics or composites. This practice is not recommended for highly nonuniform, heterogeneous, cracked, defective, or otherwise flaw-ridden samples that are unrepresentative of the nature or inherent characteristics of the material under examination.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 The 25-mm [1-in.] deflection IFD method is recommended for production screening and quality control on full size cushions only.4.2 Applicable cushion thicknesses to be tested by this test method are only those listed in this test method. Further research and development are required before this test method is applicable to other cushion thicknesses.4.3 This test method is designed to give a value approximating the 25 % IFD on a 100-mm [4-in.] thick piece of foam when the actual specimen thickness tested is within the ranges listed in the test method. In case of disagreement, the referee method is the IFD procedure in Test Methods D3574, Test B1. The user of this test method shall establish the correlation between this test method and the referee method.1.1 This test method covers a screening type quality control test used to determine if flexible polyurethane foam cushions are within the specified grade range for firmness.1.2 This test method is limited to foams with thicknesses that are 75 mm [3 in.] or greater.1.3 This test method is based on the fact that the traditional industry standard thickness for Indentation Force Deflection (IFD) is 100 mm [4 in.], and the traditional percent deflection for IFD acceptance and product planning is 25 %. With respect, then, to these traditional industry conventions, a 25 % deflection on a 100-mm [4-in.] cushion would be 25 mm [1 in.]. Thus, deflecting standard cushions (of proper 100 mm thickness) 25 mm [1 in.] provides a quick way to determine if the flexible polyurethane foam is within the specified grade range for 25 % IFD.1.4 Cushion thicknesses less than 75 mm [3 in.] shall not be tested for IFD using this test method.1.5 This test method is intended to provide a quick and simple method to screen flexible polyurethane foams for determination of its firmness grade.1.6 Units—The values stated in U.S. Customary or SI 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.1.7 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.NOTE 1: This test method and ISO 2439 address the same subject matter, but differ in technical content.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 Test Method—The pulse test method is used to determine the transmissivity and storativity of low-permeability formations surrounding the packed-off intervals. This test method is considerably shorter in duration than the pumping and slug tests used in more permeable rocks. To obtain results to the desired accuracy, pumping and slug tests in low-permeability formations are too time consuming, as indicated in Fig. 1 (from Bredehoeft and Papadopulos (1)).4 5.2 transmissivity, T—the transmissivity of a formation of thickness, b, is defined as follows: where: K   =   equivalent formation hydraulic conductivity (efhc). The efhc is the hydraulic conductivity of a material if it were homogeneous and porous over the entire interval. The hydraulic conductivity, K, is related to the equivalent formation, k, as follows: where: ρ   =   fluid density, μ   =   fluid viscosity, and g   =   acceleration due to gravity. 5.3 storativity, S—the storativity (or storage coefficient) of a formation of thickness, b, is defined as follows: where: Ss   =   equivalent bulk rock specific storage (ebrss). The ebrss is defined as the specific storage of a material if it were homogeneous and porous over the entire interval. The specific storage is given as follows: where: Cb   =   bulk rock compressibility, Cw   =   fluid compressibility, and n   =   formation porosity. 5.4 Analysis—The transient pressure data obtained using the suggested method are evaluated by the curve-matching technique described by Bredehoeft and Papadopulos (1), or by an analytical technique proposed by Wang et al (2). The latter is particularly useful for interpreting pulse tests when only the early-time transient pressure decay data are available. 5.5 Units:  5.5.1 Conversions—The permeability of a formation is often expressed in terms of the unit darcy. A porous medium has a permeability of 1 darcy when a fluid of viscosity 1 cP (1 mPa·s) flows through it at a rate of 1 cm3/s (10−6 m3/s)/1 cm2 (10−4 m2) cross-sectional area at a pressure differential of 1 atm (101.4 kPa)/1 cm (10 mm) of length. One darcy corresponds to 0.987 μm2. For water as the flowing fluid at 20°C, a hydraulic conductivity of 9.66 μm/s corresponds to a permeability of 1 darcy. Note 1: A darcy (or darcy unit) and millidarcy (md or mD) are units of permeability. They are not SI units, but are widely used in petroleum engineering and geology. A darcy has dimensional units in length. 5.5.2 Viscosity of Water—Table 1 shows the viscosity of water as a function of temperature. Note 2: The quality of the result produced by this standard is dependent on the competence of the personnel performing it and the suitability of the equipment and facility used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/observation/ and the like. Users of this standard are cautioned that compliance with Practice D3740 does not itself guarantee reliable results. Reliable results depend on many factors; D3740 provides a means of evaluating some of those factors. Note 3: The function of wells in any unconfined setting in a fractured terrain might make the determination of k problematic because the wells might only intersect tributary or subsidiary channels or conduits. The problems determining the k of a channel or conduit notwithstanding, the partial penetration of tributary channels may make determination of a meaningful number difficult. If plots of k in carbonates and other fractured settings are made and compared, they may show no indication that there are conduits or channels present, except when with the lowest probability one maybe intersected by a borehole and can be verified, such problems are described by Worthington (3) Smart, 1999 (4). Additional guidance can be found in D5717. 1.1 This test method covers a field procedure for determining the transmissivity and storativity of geological formations having permeabilities lower than 10−3 μm2 (1 millidarcy) using the pressure pulse technique. 1.2 The transmissivity and storativity values determined by this test method provide a good approximation of the capacity of the zone of interest to transmit water, if the test intervals are representative of the entire zone and the surrounding rock is fully water saturated. 1.3 Units—The values stated in SI units are to be regarded as the standard. The values in parentheses are mathematical conversions provided for information only and are not considered standard. Reporting of test results in units other than SI shall not be regarded as nonconformance with this standard. 1.4 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026, unless superseded by this standard. 1.4.1 For purposes of comparing a measured or calculated value(s) with specified limits, the measured or calculated value(s) shall be rounded to the nearest decimal or significant digits in the specified limits. 1.4.2 The procedures used to specify how data are collected/recorded or calculated in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these conditions. It is beyond the scope of this standard to consider significant digits used in analysis methods for engineering design. 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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