4.1 This test method applies to the one-dimensional laminar (viscous) flow of air in porous materials such as soil.Note 1—This test method deals with porous materials with both gaseous (air) and liquid (pore water) mobile fluids: The liquid phase is much less compressible, has a higher viscosity, and is much more tightly bound to the solid phase by chemical forces. The assumption of single-phase flow may still be presumed to be valid since the test gradient ensuring the conditions of laminar flow may be low enough that flow of the liquid phase is negligible.4.2 The degree of saturation of the specimen shall be less than that which would produce significant internal transport of pore water or alter the continuity of air voids under the applied gradients. The maximum permissible degree of saturation must be evaluated by an experienced analyst. In no instance shall the specimen be so saturated that pore water appears at the exit of the permeameter cell during the test.4.3 This test method is based on the assumption that the rate of mass flow through the specimen is constant with time.Note 2—When a specimen contains volatile materials this assumption is violated. The mass of gas flowing out will be greater than that flowing in, the gradient cannot be determined and the test may become meaningless. Such specimens pose special problems and must be decontaminated before analysis in order to minimize health and safety concerns and to prevent contamination of the test apparatus.4.4 The permeability of porous materials may be strongly dependent on a variety of physical properties including the void ratio, the degree of saturation, and percent and direction of compaction. It is beyond the scope of this test method to elaborate upon these dependencies. Rather, this test method is intended to be a measurement technique for determining the permeability under a certain set of laboratory conditions. It is the responsibility of the test requestor to specify which soil parameters must be controlled to ensure a valid extension of the test results to field conditions.4.5 Calculation of the permeability using Darcy’s law requires laminar flow conditions through the soil specimen. The conditions for laminar flow shall be evaluated by plotting the volumetric flow rate of air through the specimen against the pressure drop across the specimen. If the individual test points lie within 25 % of a straight line passing through the origin, then laminar flow conditions are present and Darcy's law may be used to calculate the permeability.Note 3—The permeability calculated using this standard is valid only when the degree of saturation does not change over time. Long measurement times associated with the use of bubble meters and manometers may indirectly lead to variability when measuring flow versus pressure drop (see 8.2) due to evaporation. The recommended use of digital electronic flow and pressure sensors leads to considerably reduced measurement times because the user can quickly determine by inspection when a steady state condition has been reached. At that point only a single reading needs to be taken for a reliable measurement. A rapid course of measurement will minimize dehydration of unsaturated specimens.Note 4—Humidifying the test gas to minimize specimen dehydration is not recommended because: (1) there is no practical way to either measure or control the relative humidity of the test gas, either at the inlet or outlet of the specimen; (2) the calibration of typical digital flowmeters are generally for dry air only and would become unreliable in the presence of water vapor, especially in view of the potential for irreversible adsorption of moisture on the sensor elements; (3) there is a danger of permanent water condensation in the static transfer lines and other apparatus dead volumes; and (4) the test apparatus would become more complex and difficult to use.4.6 This test method covers the use of two different types of permeameter cells (flexible and rigid wall permeameters) and two types of air flow regulation (mass flow control and pressure control).4.7 A flexible wall permeameter is the preferred means for confining the test specimen in accordance with Test Methods D5084, D4525, and D4767. This test method may still be performed using a rigid wall permeameter, but all reference to effective confining stress and the permeameter cell pressure system shall then be disregarded.4.8 For some specimens, the permeability will be strongly dependent on the effective confining stress due to porosity reduction. Whenever possible, the requestor shall specify the field overburden conditions at which this test method is to be performed. In some specimens, this stress will vary significantly with flow in an indeterminate way. All specimens shall be evaluated for this effect by performing this test method at two or more different confining stress values when a flexible wall permeameter is used.4.9 This test method is intended to support soil remediation operations such as: soil vapor extraction, air sparging, backfilling of soils in utility trenches, and similar engineering activities.4.10 The correlation between results obtained with this test method and in situ field measurements has only been partially established. The small laboratory specimen used in this method may not be representative of the distributed condition on-site due to vadose zone fluctuations, changes in soil stratigraphy, and so forth. For this reason, caution should be used by qualified personnel when applying laboratory test results to field situations.Note 5—This test method is dependent on the competence of the personnel performing it and the suitability of the equipment and facilities used. Agencies which meet the criterion of Practice D3740 are generally considered capable of competent and objective testing.1.1 This test method covers laboratory determination of the coefficient of permeability for the flow of air through unsaturated porous materials.1.2 This test method may be used with intact or compacted coarse grained soils, silts, or lean cohesive soils that have a low degree of saturation and that have permeability between 1.0 × 10-15 m2 (1.01 millidarcy) and 1.0 × 10-10 m2 (101 darcy).1.3 The values stated in SI units are to be regarded as standard.1.3.1 By tradition in U.S. practice, the permeability of porous media is reported in units of darcy, although the SI unit for permeability is m2.1.4 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.1.4.1 For the purpose of comparing a measured or calculated value with specified limits, the measured or calculated value shall be rounded to the same precision as 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 considerations. 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 and health practices and determine the applicability of regulatory limitations prior to use.

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4.1 The purpose of this test is to obtain, by means of a specified laboratory procedure, the values of the equilibrium moisture content at higher RH levels ((≈ 95 to 100%). These values are used either as means to characterize the material or as material characteristics needed as input to appropriate computer models that can simulate wetting or drying potential of individual building materials or material assemblies under specified environmental conditions.1.1 This test method specifies a laboratory procedure for the determination of the water retention curve (or moisture storage capacity) of porous building materials at very high relative humidity (RH) levels (≈ 95 to 100% RH) corresponding to the capillary moisture region of the sorption isotherm. This is achieved by using the pressure plate test apparatus. This technique was originally developed to study soil moisture content and eventually had been adapted to building construction materials.1.2 At higher RH levels (≈ 95 to 100% RH) of the sorption isotherm (see Test Method C1498), use of climatic chamber is not an option. This technique uses overpressure to extract water out of the pore structure of porous materials until equilibrium between the moisture content in the specimens and the corresponding overpressure is achieved. Using the pressure plate extractors, equilibrium can only be reached by desorption.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 There are several purposes of this test:5.1.1 For transmission loss: (a) to characterize the sound insulation characteristics of materials in a less expensive and less time consuming approach than Test Method E90 and ISO 140-3 (“reverberant room methods”), (b) to allow small samples tested when larger samples are impossible to construct or to transport, (c) to allow a rapid technique that does not require an experienced professional to run.5.1.2 For transfer matrix: (a) to determine additional acoustic properties of the material; (b) to allow calculation of acoustic properties of built-up or composite materials by the combination of their individual transfer matrices.5.2 There are significant differences between this method and that of the more traditional reverberant room method. Specifically, in this approach the sound impinges on the specimen in a perpendicular direction (“normal incidence”) only, compared to the random incidence of traditional methods. Additionally, revereration room methods specify certain minimum sizes for test specimens which may not be practical for all materials. At present the correlation, if any, between the two methods is not known. Even though this method may not replicate the reverberant room methods for measuring the transmission loss of materials, it can provide comparison data for small specimens, something that cannot be done in the reverberant room method. Normal incidence transmission loss may also be useful in certain situations where the material is placed within a small acoustical cavity close to a sound source, for example, a closely-fitted machine enclosure or portable electronic device.5.3 Transmission loss is not only a property of a material, but is also strongly dependent on boundary conditions inherent in the method and details of the way the material is mounted. This must be considered in the interpretation of the results obtained by this test method.5.4 The quantities are measured as a function of frequency with a resolution determined by the sampling rate, transform size, and other parameters of a digital frequency analysis system. The usable frequency range depends on the diameter of the tube and the spacing between the microphone positions. An extended frequency range may be obtained by using tubes with various diameters and microphone spacings.5.5 The application of materials into acoustical system elements will probably not be similar to this test method and therefore results obtained by this method may not correlate with performance in-situ.1.1 This test method covers the use of a tube, four microphones, and a digital frequency analysis system for the measurement of normal incident transmission loss and other important acoustic properties of materials by determination of the acoustic transfer matrix.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 This practice provides a protocol to compare different decontamination technologies with a standard contamination mechanism and analysis of subsequent decontamination factors/efficiencies.5.2 The use of this practice provides for the preparation of test coupons with a known amount of fixed radiological or surrogate contaminant on the surface.5.3 A standard test coupon is described and a list of potential spray equipment, contaminants, and contaminating solutions is provided within the procedure.5.4 This method describes a contamination simulation process that meets the requirements of testing performed (previously) by the U.S. Department of Energy and U.S. Environmental Protection Agency.1.1 This practice is intended to provide a basis for simulating radioactive contamination consistent with processes used to evaluate decontamination. The methods described provide a “fixed-type” radiological or surrogate contamination on porous surfaces; these methods provide a surface contamination that is not easily removed by brushing or flushing with water.1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.1.3 This practice is intended to be practiced primarily on porous surfaces such as concrete, marble, granite, grout, brick, tile, asphalt, vinyl floor tile, latex painted gypsum wall board and polyurethane coated wood. Preparation of non-porous substrates is not addressed, although similar methodology may be used.1.4 The chemical simulants shall not include nor generate toxic by-products as defined by U.S. Occupational Safety and Health Administration (OSHA) during preparation, application, or removal under normal conditions. A Safety Data Sheet shall be provided so that appropriate PPE can be selected.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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This specification covers porous nonreinforced concrete pipe for use in underdrains. Pipe manufactured according to this specification shall be of two classes identified as “standard porous nonreinforced concrete pipe”, and “extra-strength porous nonreinforced concrete pipe. ” The concrete shall consist of cementitious materials, mineral, aggregates, and water. The joints shall be of such design and the ends of the concrete pipe sections so formed that the pipe can be laid together to make a continuous line pipe. The aggregates shall be sized, graded, proportioned, and mixed with such proportions of cementitious materials, and water as will produce a homogeneous concrete mixture of such quality that the pipe will conform to test and design requirements. Pipe shall be subjected to curing. Special shapes or fittings for use with concrete pipe conforming to this specification shall be made of porous or nonporous concrete in such manner as will provide strength at least equal to the class of the adjacent pipe to which they are joined; and shall conform to all other requirements specified for pipe. The test pipe shall freed from all visible moisture. When dry, each pipe shall be measured and inspected. The crushing strength of the porous material as well as its infiltration, shall conform to the requirements.1.1 This specification covers porous nonreinforced concrete pipe for use in underdrains.1.2 A complete metric companion to this specification has been developed— 654M; therefore, no metric equivalents are presented in this specification.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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This specification covers porous nonreinforced concrete pipe for use in underdrains. Pipe manufactured according to this specification shall be of two classes identified as “standard porous nonreinforced concrete pipe”, and “extra-strength porous nonreinforced concrete pipe. ” The concrete shall consist of cementitious materials, mineral, aggregates, and water. The joints shall be of such design and the ends of the concrete pipe sections so formed that the pipe can be laid together to make a continuous line pipe. The aggregates shall be sized, graded, proportioned, and mixed with such proportions of cementitious materials, and water as will produce a homogeneous concrete mixture of such quality that the pipe will conform to test and design requirements. Pipe shall be subjected to curing. Special shapes or fittings for use with concrete pipe conforming to this specification shall be made of porous or nonporous concrete in such manner as will provide strength at least equal to the class of the adjacent pipe to which they are joined; and shall conform to all other requirements specified for pipe. The test pipe shall freed from all visible moisture. When dry, each pipe shall be measured and inspected. The crushing strength of the porous material as well as its infiltration, shall conform to the requirements.1.1 This specification covers porous nonreinforced concrete pipe for use in underdrains.1.2 This specification is the metric counterpart of Specification C654.1.3 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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4.1 This document describes the basic principles that need to be followed to obtain a mean value of the Darcy permeability coefficient for structures that consist of a series of interconnected voids or pores. The coefficient is a measure of the permeability of the structure to fluid flowing through it that is driven by a pressure gradient created across it.4.2 The technique is not sensitive to the presence of closed or blind-end pores (Fig. 1).FIG. 1 Schematic of the Different Pores Types Found in Tissue Scaffolds. Fluid Flow Through the Structure is via the Open Pores4.3 Values of the permeability coefficient can be used to compare the consistency of manufactured samples or to determine what the effect of changing one or more manufacturing settings has on permeability. They can also be used to assess the homogeneity and anisotropy of tissue scaffolds. Variability in the permeability coefficient can be also be indicative of:4.3.1 Internal damage within the sample, for example, cracking or permanent deformation.4.3.2 The presence of large voids, including trapped air bubbles, within the structure.4.3.3 Surface effects such as a skin formed during manufacture.4.3.4 Variable sample geometry.4.4 This test method is based on the assumption that the flow rate through a given sample subjected to an applied pressure gradient is constant with time.NOTE 1: If a steady-state flow condition isn’t reached, then this could be due to structural damage (that is, crack formation or the porous structure deformed as a result of the force being placed upon it by the fluid flowing through it). Sample deformation in the form of stretching (bowing) can also occur for less resilient structures as a result of high fluid flow rates. This topic is discussed in more detail in Section 7.4.5 Care should be taken to ensure that hydrophobic materials are fully wetted out when using water or other aqueous-based liquids as permeants.4.6 Conventionally, the pressure differential created across a sample is measured as a function of both increasing and decreasing flow rates. An alternative approach, which may be practically easier to create, is to apply a range of different pressure differentials across the sample and measure the resultant flow of fluid through it. The hysteresis that occurs during a complete cycle of increasing flow rate followed by a progressive decrease in flow rate can provide an excellent measure of the behavioural consistency of the matrix. Significant hysteresis in the measured pressure differential during increasing and decreasing flow rates can indicate the existence of induced damage in the structure, the fact that the material is behaving viscoelastically, or is suffering from permanent plastic deformation. Some guidance on how to identify which of these factors is responsible for hysteresis is provided in Section 7.4.7 It is assumed that Darcy’s law is valid. This can be established by plotting the volume flow through the specimen against the differential pressure drop across the specimen. This plot should be linear for Darcy’s law to apply and a least-squares fit to the data should pass through the origin. It is not uncommon for such plots to be nonlinear which may indicate that the structure does not obey Darcy’s law or that the range of pressures applied is too broad. This topic is further discussed in Section 7.1.1 This guide describes test methods suitable for determining the mean Darcy permeability coefficient for a porous tissue scaffold, which is a measure of the rate at which a fluid, typically air or water, flows through it in response to an applied pressure gradient. This information can be used to optimize the structure of tissue scaffolds, to develop a consistent manufacturing process, and for quality assurance purposes.1.2 The method is generally nondestructive and non-contaminating.1.3 The method is not suitable for structures that are easily deformed or damaged. Some experimentation is usually required to assess the suitability of permeability testing for a particular material/structure and to optimize the experimental conditions.1.4 Measures of permeability should not be considered as definitive metrics of the structure of porous tissue scaffolds and should complement measures obtained by other investigative techniques, for example, scanning electron microscopy, gas flow porometry, and micro-computer X-ray tomography (Guides F2450, F2603, and F3259).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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6.1 This test method has been developed as a result of research performed by Air Dispersion Limited (Manchester, UK) and funded by the Barrier Test Consortium Limited. The results of this research have been published in a peer-reviewed journal.4 This research demonstrated that testing the barrier performance of porous packaging materials using microorganisms correlates with measuring the filtration efficiency of the materials.6.2 This test method does not require the use of microbiological method; in addition, the test method can be conducted in a rapid and timely manner.6.3 When measuring the filtration efficiency of porous packaging materials a typical filtration efficiency curve is determined (see Fig. 1). Since the arc of these curves is dependent upon the characteristics of each individual material, the appropriate way to make comparison among materials is using the parameter that measures maximum penetration through the material.FIG. 1 A Typical Curve Showing Penetration as a Function of Flow RateNOTE 1: The point of maximum penetration is indicated by the upward pointing triangle.6.4 The particle filtration method is a quantitative procedure for determining the microbial barrier properties of materials using a challenge of 1.0 µm particles over range of pressure differentials from near zero to approximately 30 cm water column (WC) (2942 Pa). This test method is based upon the research of Tallentire and Sinclair4 and uses physical test methodology to allow for a rapid determination of microbial barrier performance.1.1 This test method measures the aerosol filtration performance of porous packaging materials by creating a defined aerosol of 1.0 μm particles and assessing the filtration efficiency of the material using either single or dual particle counters.1.2 This test method is applicable to porous materials used to package terminally sterilized medical devices.1.3 The intent of this test apparatus is to determine the flow rate through a material at which maximum penetration occurs.1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.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 Landscaping and construction professionals and golf course designers are a few of the typical users of this standard. When physically evaluating a soil, relative to its suitability to support plant growth (primarily grasses), tests must be performed to determine the presence and amount of solid matter compatibility that is then used to determine potential air-void content, water-holding ability, and deleterious materials. Rotary kiln produced porous ceramic material is a mineral amendment that can be added to a topsoil to increase its suitability to support plant growth.5.2 Typical general ranges of soil content for suitable topsoils are presented in Specification D5268. It should be recognized, however, that in some geographic regions, concurrence with the values in the referenced table could be difficult. In such situations, locally acceptable specifications need to be developed.NOTE 1: 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 facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/ and the like. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.1.1 This practice covers the material characteristics, physical requirements, and sampling appropriate for the designation of the rotary kiln produced porous ceramic material as a mineral amendment. The porous ceramic material can be used to replace the sand content of a topsoil or it can be blended into an existing topsoil. Typically 5-20 % by mass of porous ceramics are used when blending with or adding to a topsoil.1.2 The potential/success of a topsoil amendment is measured/determined by its ability to provide or enhance some or all of the desired properties/characteristics of the topsoil that may be deficient in the unamended topsoil.1.3 Soils typically consist of three components: water, air and solids. Solids can be further divided into two sub-components: organic matter, such as peat, muck or other decayed matter, and inorganic mineral matter, such as clay, silt and sand. Porous ceramic falls into the inorganic mineral matter sub-component and is generally used in horticultural topsoil applications as a substitute/alternative or addition for the sand component of soil. See Specification D5268, Table 1.1.4 Units—The values stated in SI units are to be regarded as the standard. The values given in parentheses are 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.1.5 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026, unless superseded by this test method.1.5.1 The procedures used to specify how data are collected/recorded and calculated in the 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 considerations. It is beyond the scope of these test methods to consider significant digits used in analysis methods for engineering data.1.6 This practice offers a set of instructions for performing one or more specific operations. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of this practice may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a project’s many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus process.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 Harmful biological or particulate contaminants may enter the medical package through leaks. These leaks are frequently found at seals between package components of the same or dissimilar materials. Leaks may also result from a pinhole in the packaging material.4.2 It is the objective of this test method to visually observe the presence of channel defects by the leakage of dye through them.4.3 This dye penetrant procedure is applicable only to individual leaks in a package seal. The presence of a number of small leaks, as found in porous packaging material, which could be detected by other techniques, will not be indicated.4.4 There is no general agreement concerning the level of leakage that is likely to be deleterious to a particular package. However, since these tests are designed to detect leaks, components that exhibit any indication of leakage are normally rejected.4.5 These procedures are suitable to verify and locate leakage sites. They are not quantitative. No indication of leak size can be inferred from these tests. The methods are usually employed as a pass/fail test.4.6 The dye solution will wick through any porous material over time, but usually not within the maximum time suggested. If wicking does occur, it may be verified by observing the porous side of the subject seal area. The dye will have discolored the surface of the material. Refer to Appendix X1 for details on wicking and guidance on the observance of false positives.1.1 This test method defines materials and procedures that will detect and locate a leak equal to or greater than a channel formed by a 50 µm (0.002 in.) wire in package edge seals formed between a transparent material and a porous sheet material. A dye penetrant solution is applied locally to the seal edge to be tested for leaks. After contact with the dye penetrant for a specified time, the package is visually inspected for dye penetration.1.2 Three dye application methods are covered in this test method: injection, edge dip, and eyedropper.1.3 These test methods are intended for use on packages with edge seals formed between a transparent material and a porous sheet material. The test methods are limited to porous materials which can retain the dye penetrant solution and prevent it from discoloring the seal area for a minimum of 5 seconds. Uncoated papers are especially susceptible to leakage and must be evaluated carefully for use with each test method.1.4 These test methods require that the dye penetrant solution have good contrast to the opaque packaging material.1.5 The values are stated in International System of Units (SI units) and English units. Either is to be regarded as 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 and health practices and determine the applicability of regulatory limitations prior to use.

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5.1 Harmful biological or particulate contaminants may enter the package through incomplete seals or imperfections such as pinholes or cracks in the trays.5.2 After initial instrument set-up and calibration, the operations of individual tests and test results do not need operator interpretation. The non-destructive nature of the test may be important when testing high value added products.5.3 Leak test results that exceed the permissible threshold setting are indicated by audible or visual signal responses, or both, or by other means.5.4 This non-destructive test method may be performed in either laboratory or production environments. This testing may be undertaken on either a 100 % or a statistical sampling basis. This test method, in single instrument use and current implementation, may not be fast enough to work on a production packaging line, but is well suited for statistical testing as well as package developmental design work.1.1 This non-destructive test method detects leaks in non-porous rigid thermoformed trays, as well as the seal between the porous lid and the tray. The test method detects channel leaks in packages as small as 100 μm (0.004 in.) diameter in the seal as well as 50 μm (0.002 in.) diameter pinholes, or equivalently sized cracks in the tray, subject to trace gas concentration in the package, package design and manufacturing tolerances.NOTE 1: This test method does not claim to challenge the porous (breathable) lidding material. Any defects that may exist in the porous portion of the package will not be detected by this test method.1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units 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, 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 Porous articles (often textiles) are often treated with antimicrobial agents to reduce the growth of microorganisms during use, in storage, or while waiting to be laundered, or both. Additionally, antimicrobial agents are added to reduce or control the overall microbial growth on porous articles that may affect the material’s odor, visual, chemical or physical integrity, or both.5.2 Antimicrobial textile test methods that measure the antimicrobial behavior of treated textiles do exist but they are often specific for one type of antimicrobial agent or are designed to or may artificially (not expected in real life) promote the release of some specific antibacterial agents over others. This test method is designed to be able to measure the antimicrobial activity from all common antimicrobial agents used to treat porous articles, including textiles, without giving either positive or negative bias to one type of chemistry or product over another.5.3 In an effort to avoid excessive use or abuse of antimicrobial agents in the environment, it is important to understand if untreated porous articles are susceptible to microbial contamination and growth. In this test method, a small amount of nutrients is added to each test sample in order to promote some microbial growth on susceptible test samples but not enough to overwhelm potential antimicrobial agents that may be effective in real life situations. Furthermore, low levels of nutrients allow investigators to add soiling agents that may be more reflective of a specific treated product’s end use or expected performance.5.4 Very specific parameters are identified within this method to limit any variability that may be seen between laboratories. Identifying and clarifying potential variables found in other guides or methods used in the industry will allow for better reproducibility and repeatability between and within laboratories.5.5 This test method provides the foundation for conducting tests on porous antibacterial treated articles. Modifications of this method that simulate intended use, durability and compatibility of the treated article should be outlined to ensure an accurate assessment of antimicrobial activity with each particular biocide that substantiates end use claims made for the article. A list of these typical modifications and current test methods for textiles can be found in Guide E2922.5.6 This test method is appropriate for porous materials such as textiles, paper, or similar porous materials. It is intended to measure the antibacterial properties of such materials. In most instances, further studies will be required to support and substantiate actual claims being made for the performance of treated materials in practice or as part of a regulatory process.5.7 This test method or indicated modifications may be used to determine antimicrobial activity as indicated in 5.6 or may be used as a routine bioassay in standard quality control programs.1.1 To determine the bactericidal or bacteriostatic properties of porous articles treated with an active biocidal agent, samples of porous treated materials, such as textiles or paper, are inoculated with a defined suspension of microorganisms and then incubated. The changes in numbers of the bacterial populations on the treated article are compared with untreated articles either over designated time or they are compared to the initial bacterial population at “zero time” for the treated article to measure antibacterial properties.1.2 This test method is used for measuring the quantitative antibacterial activity of porous materials that have been treated with a biocide to inhibit the growth of bacteria on the treated materials. This method may also be used to measure the ability of the treated material to inhibit the growth of a microorganism. It can measure both bactericidal and bacteriostatic activity.1.3 This test method shall be performed by individuals experienced and adept in microbiological procedures and in facilities suitable for the handling of the microorganisms under test.1.4 This test method 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.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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Recent results have demonstrated that direct measurements of unsaturated transport parameters, for example, hydraulic conductivity, vapor diffusivity, retardation factors, thermal and electrical conductivities, and water potential, on subsurface materials and engineered systems are essential for defensible site characterization needs of performance assessment as well as restoration or disposal strategies. Predictive models require the transport properties of real systems that can be difficult to obtain over reasonable time periods using traditional methods. Using a SSC-UFA greatly decreases the time required to obtain direct measurements of hydraulic conductivity on unsaturated systems and relatively impermeable materials. Traditionally, long times are required to attain steady-state conditions and distributions of water because normal gravity does not provide a large enough driving force relative to the low conductivities that characterize highly unsaturated conditions or highly impermeable saturated systems (Test Method D5084). Pressure techniques sometimes can not be effective for measuring unsaturated transport properties because they do not provide a body force and cannot act on the entire specimen simultaneously unless the specimen is saturated or near-saturated. A body force is a force that acts on every point within the system independently of other forces or properties of the system. High pressures used on saturated systems often induce fracturing or grain rearrangements and cause compaction as a result of high-point stresses that are generated within the specimen. A SSC-UFA does not produce such high-point stresses.There are specific advantages to using centrifugal force as a fluid driving force. It is a body force similar to gravity and, therefore, acts simultaneously over the entire system and independently of other driving forces, for example, gravity or matric potential. Additionally, in a SSC-UFA the acceleration can dominate any matric potential gradients as the Darcy driving force. The use of steady-state centrifugation to measure steady-state hydraulic conductivities has recently been demonstrated on various porous media (1,2).Several issues involving flow in an acceleration field have been raised and addressed by previous and current research (1,4). These studies have shown that compaction from acceleration is negligible for subsurface soils at or near their field densities. Bulk densities in these specimens have remained constant (±0.1 g/cm3) because the specimens are already compacted more than the acceleration can affect them. The notable exception is structured soils. Special arrangements must be made to preserve their densities, for example, the use of speeds not exceeding specific equivalent stresses. As an example, for most SSC-UFA specimen geometries, the equivalent pressure in the specimen at a rotation speed of 2500 rpm is about 2 bar. If the specimen significantly compacts under this pressure, a lower speed must be used. Usually, only very fine soils at dry bulk densities less than 1.2 g/cm3 are a problem. Whole rock, grout, ceramics, or other solids are completely unaffected by these accelerations. Precompaction runs up to the highest speed for that run are performed in the SSC-UFA prior to the run to observe any compaction effects.Three-dimensional deviations of the driving force as a function of position in the specimen are less than a factor of two. Theoretically, the situation under which unit gradient conditions are achieved in a SSC-UFA, in which the change in the matric potential with radial distance equals zero (dψ/dr = 0), is best at higher water flux densities, higher speeds, or coarser grain-size, or combination thereof. This is observed in potential gradient measurements in the normal operational range where dψ/dr = 0. The worst case occurs at the lowest water flux densities in the finest-grained materials (1).There is no sidewall leakage problem in the SSC-UFA for soils. The centrifugal force maintains a good seal between the specimen and the wall. As the specimen desaturates, the increasing matric potential (which still operates in all directions although there is no potential gradient) keeps the water within the specimen, and the acceleration (not being a pressure) does not force water into any larger pore spaces such as along a wall. Therefore, capillary phenomena still hold in the SSC-UFA, a fact which is especially important for fractured or heterogeneous media (2). Cores of solid material such as rock or concrete, are cast in epoxy sleeves as their specimen holder, and this also prevents sidewall leakage.The SSC-UFA can be used in conjunction with other methods that require precise fixing of the water content of a porous material. The SSC-UFA is used to achieve the steady-state water content in the specimen and other test methods are applied to investigate particular problems as a function of water content. This has been successful in determining diffusion coefficients, vapor diffusivity, electrical conductivity, monitoring the breakthrough of chemical species (retardation factor), pore water extraction, solids characterization, and other physical or chemical properties as functions of the water content (2,5).Hydraulic conductivity can be very sensitive to the solution chemistry, especially when specimens contain expandable, or swelling, clay minerals. Water should be used that is appropriate to the situation, for example, groundwater from the site from which the specimen was obtained, or rainwater if an experiment is being performed to investigate infiltration of precipitation into a disposal site. Appropriate antimicrobial agents should be used to prevent microbial effects within the specimen, for example, clogging, but should be chosen with consideration of any important chemical issues in the system. A standard synthetic pore water solution, similar to the solution expected in the field, is useful when it is difficult to obtain field water. Distilled or deionized water is generally not useful unless the results are to be compared to other tests using similar water or is specified in pertinent test plans, ASTM test methods, or EPA procedures. Distilled water can dramatically affect the conductivity of soil and rock specimens that contain clay minerals, and can induce dissolution/precipitation within the specimen.This test method establishes a dynamic system, and, as such, the steady-state water content is usually higher than that which is attained during a pressure plate or other equilibrium method that does not have flow into the specimen during operation. This is critical when using either type of data for modeling purposes. This test method does not measure water vapor transport or molecular diffusion of water, both of which become very significant at low conductivities, and may actually dominate when hydraulic conductivities drop much below 10–10 cm/s.The quality of the result produced by this test method depends upon the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing and sampling. Users of this test method are cautioned that compliance with Practice D3740 does not in itself ensure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.1.1 This test method covers the determination of the hydraulic conductivity, or the permeability relative to water, of any porous medium in the laboratory, in particular, the hydraulic conductivity for water in subsurface materials, for example, soil, sediment, rock, concrete, and ceramic, either natural or artificial, especially in relatively impermeable materials or materials under highly unsaturated conditions. This test method covers determination of these properties using any form of steady-state centrifugation (SSC) in which fluid can be applied to a specimen with a constant flux or steady flow during centrifugation of the specimen. This test method only measures advective flow on core specimens in the laboratory.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 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 and health practices and determine the applicability of regulatory limitations prior to use.

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This specification covers the raw material and final product requirements, and the associated test methods for the selection of porous high density and ultra high molecular weight polyethylenes intended for use in surgical implants. The porous polyethylene may be used as a free standing product or as a coating on a substrate in nonloaded applications. Physical properties such as pore size and volume, as well as tensile, compressive, flexural, and shear properties shall be determined, but will be specified in the particular device to which its end use shall be applied.1.1 This specification covers the properties and test methods for porous high-density-polyethylene (HDPE) and porous ultra-high-molecular-weight-polyethylene (UHMWPE) intended for use in surgical implants. The porous polyethylene may be used as a free-standing product or as a coating on a substrate in non-loaded applications.1.2 Materials covered by this standard can have a broad range of mechanical and morphological properties depending on the starting material and fabrication processes. Therefore no attempt has been made to standardize the properties, and the requirements for a specific application are not within the scope of this standard.1.3 Evaluation of the tissue response to a porous polyethylene must be completed. Guidance in establishing biocompatibility may be found in the list of references.1.4 Clinical experience and animal studies have shown that tissue will grow into the open pores of porous polyethylene. The tissue ingrowth into the pores may facilitate the establishment of implant fixation.1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 This test method applies to one-dimensional, laminar flow of water within laboratory-compacted, porous materials such as soil.4.2 The hydraulic conductivity of porous materials generally decreases with an increasing amount of air in the pores of the material. This test method applies to porous materials containing little or no air. The test method is designed to minimize the amount of air in the test specimen. However, this test method does not ensure complete saturation of the test specimen with water. In cases where it is essential to saturate the test specimen fully with water, the compacted specimen may be tested using Test Method D5084.4.3 This test method applies to permeation of porous materials with water. Permeation with other liquids, such as chemical wastes, can be accomplished using procedures similar to those described in this test method. However, this test method is only intended to be used when water is the permeant liquid.4.4 It is assumed that Darcy's law is valid and that the hydraulic conductivity is essentially unaffected by hydraulic gradient. The validity of Darcy’s law may be evaluated by measuring the hydraulic conductivity of the specimen at three hydraulic gradients; if all measured values are similar (within 25 %), then Darcy’s law may be taken as valid. However, when the hydraulic gradient acting on a test specimen is changed, the state of stress will also change, and, if the specimen or pore fluid is compressible, the volume of the test specimen or pore fluid will change. Thus, some change in hydraulic conductivity may occur when the hydraulic gradient is altered, even in cases where Darcy’s law is valid.4.5 One potential problem with this method of testing is the possibility that water will flow along the interface between the test specimen and the compaction/permeameter ring. The problem tends to be of minimal significance for materials that swell when exposed to water (for example, compacted, clayey soils) but can be a very serious problem for materials that might tend to shrink and pull away from the walls of the permeameter. Test Method D5084 is recommended for any material that tends to shrink when exposed to the permeant liquid.4.6 The correlation between results obtained with this test method and the hydraulic conductivities of in-place, compacted materials has not been fully investigated. Experience has sometimes shown that flow patterns in small, laboratory-prepared test specimens do not necessarily follow the same patterns on large field scales and that hydraulic conductivities measured on small test specimens are not necessarily the same as larger-scale values. Therefore, the results should be applied to field situations with caution and by qualified personnel.NOTE 1: 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 facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself ensure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.1.1 This test method covers laboratory measurement of the hydraulic conductivity (also referred to as coefficient of permeability) of laboratory-compacted materials with a rigid-wall, compaction-mold permeameter.1.2 This test method may be used with laboratory-compacted specimens that have a hydraulic conductivity less than or equal to 1 × 10−5 m/s. The hydraulic conductivity of compacted materials that have hydraulic conductivities greater than 1 × 10−5 m/s may be determined by Test Method D2434.1.3 Units—The values stated in SI units are to be regarded as the standard, unless other units are specifically given. By tradition in U.S. practice, hydraulic conductivity is reported in cm/s, although the common SI units for hydraulic conductivity are m/s.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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