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ASTM E1397-91(2008) Standard Practice for In Vitro Rat Hepatocyte DNA Repair Assay (Withdrawn 2014) Withdrawn, No replacement 发布日期 :  1970-01-01 实施日期 : 

Measurement of chemically induced DNA repair is a means of assessing the ability of a chemical to reach and alter the DNA. DNA repair is an enzymatic process that involves the recognition and excision of DNA-chemical adduct followed by DNA strand polymerization and ligation to restore the original primary structure of the DNA (7). This process can be quantitated by measuring the amount of labeled thymidine incorporated into the nuclear DNA of cells that are not in S-phase and is often called unscheduled DNA synthesis (UDS) (8). Numerous assays have been developed for the measurement of chemically induced DNA repair in various cell lines and primary cell cultures from both rodent and human origin (9). The primary rat hepatocyte DNA repair assay developed by Williams (10) has proven to be particularly valuable in assessing the genotoxic activity and potential carcinogenicity of chemicals (11), (12). Genotoxic activity is often produced by reactive metabolites of a chemical. The in vitro rat hepatocyte assay provides a system in which a metabolically competent cell is itself the target cell for measured genotoxicity. Most other short-term tests for genotoxicity employ a rat liver homogenate (S-9) for metabolic activation, which differs markedly in many important ways from the patterns of activation and detoxification that actually occur in hepatocytes. An extensive literature is available on the use of in vitro hepatocyte DNA repair assays (2, 3, 6, 13-28).1.1 This practice covers a typical procedure and guidelines for conducting the rat in vitro hepatocyte DNA repair assay. The procedures presented here are based on similar protocols that have been shown to be reliable (1-6) . 1.2 Mention of trade names or commercial products are meant only as examples and not as endorsements. Other suppliers or manufacturers of equivalent products are acceptable. 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 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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ASTM E1398-91(2008) Standard Practice for In Vivo Rat Hepatocyte DNA Repair Assay (Withdrawn 2014) Withdrawn, No replacement 发布日期 :  1970-01-01 实施日期 : 

Measurement of chemically induced DNA repair is a means of assessing the ability of a chemical to reach and alter the DNA. DNA repair is an enzymatic process that involves recognition and excision of DNA-chemical adducts, followed by DNA strand polymerization and ligation to restore the original primary structure of the DNA (6). This process can be quantitated by measuring the amount of labeled thymidine incorporated into the nuclear DNA of cells that are not in S-phase and is often called unscheduled DNA synthesis (UDS) (7). Numerous assays have been developed for the measurement of chemically induced DNA repair in various cell lines and primary cell cultures from both rodent and human origin (4). The primary culture rat hepatocyte DNA repair assay has proven to be particularly valuable in assessing the genotoxic activity of chemicals (8). Genotoxic activity often results from metabolites of a chemical. The in vitro rat hepatocyte assay provides a system in which a metabolically competent cell is also the target cell. Most other in vitro short-term tests for genotoxicity employ a rat liver homogenate (S-9) for metabolic activation, which differs markedly in many important ways from the patterns of activation and detoxification that actually occur in hepatocytes. An extensive literature is available on the use of in vitro DNA repair assays (9-19).A further advance was the development of an in vivo rat hepatocyte DNA repair assay in which the test chemical is administered to the animal and the resulting DNA repair is assessed in hepatocytes isolated from the treated animal (20). Numerous systems now exist to measure chemically induced DNA repair in specific tissues in the whole animal (4). The average of in vivo assays is that they reflect the complex patterns of uptake, distribution, metabolism, detoxification, and excretion that occur in the whole animal. Further, factors such as chronic exposure, sex differences, and different routes of exposure can be studied with these systems. This is illustrated by the potent hepatocarcinogen 2,6-dinitrotoluene (DNT). Metabolic activation of 2,6-DNT involves uptake, metabolism by the liver, excretion into the bile, reduction of the nitro group by gut flora, readsorption, and further metabolism by the liver once again to finally produce the ultimate genotoxicant (21). Thus, 2,6-DNT is negative in the in vitro hepatocyte DNA repair assay (22) but is a very potent inducer of DNA repair in the in vivo DNA repair assay (23, 24). A problem with tissue-specific assays is that they may fail to detect activity of compounds that produce tumors in other target tissues. For example, no activity is seen in the in vivo DNA repair assay with the potent mutagen benzo(a)pyrene (BP), probably because limited tissue distribution and greater detoxification in the liver yields too few DNA adducts to produce a measurable response (3). In contrast, BP is readily detected in the less tissue-specific in vitro hepatocyte DNA repair assay (11). An extensive literature exists on the use of the in vivo hepatocyte DNA repair assay (1-3, 5, 9, 25-33).1.1 This practice covers a typical procedure and guidelines for conducting the rat in vivo hepatocyte DNA repair assay. The procedures presented here are based on similar protocols that have been shown to be reliable (1, 2, 3, 4, 5).1.2 Mention of trade names or commercial products are meant only as examples and not as endorsements. Other suppliers or manufacturers of equivalent products are acceptable.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 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 This practice is for use by design engineers, specifiers, regulatory agencies, owners, installers, and inspection organizations who are involved in the rehabilitation of pipes through the use of a Mechanical Trenchless Point Repair Sleeve with a Locking Gear Mechanism for Pipes of Varying Inner Diameter and Offset Joints within a damaged existing pipe.4.2 This practice applies to the following types of defects in pipe that can be repaired: longitudinal, radial and circumferential cracks, fragmentation, leaking joints, displacement or joint misalignment, closing or sealing unused laterals, corrosion, spalling, wear, leaks in the barrel of the pipe, deformation in the pipe and root penetration. There are no limitations on the diameters of the laterals that can be sealed. The degree of deformation that can be repaired is dependent on the minimum and maximum diameters for which the sleeve is applicable as listed in the tables of dimensions shown in Appendix X1 but shall never exceed 5 %.4.3 This practice applies to pipes made of vitrified clay, concrete, reinforced concrete, plastics, glass reinforced plastics, cast iron, ductile iron and steel for both pressure and non-pressure applications.4.4 In this practice, no issues of snagging waste or build-up of sludge or sediment have been recorded to date; the performance of this sleeve, however, depends on many factors; therefore, past operational records may not include all possible future conditions under which the user may install these sleeves.4.5 The suitability of the technology covered in this practice for a particular application shall be jointly decided by the authority, the engineer and the installer.1.1 This practice establishes minimum requirements for good practices for the materials and installation of mechanical trenchless repair sleeve with a locking gear mechanism for pipes of varying inner diameter and offset joints in the range of 6 in. to 72 in. (150 mm to 1800 mm).1.2 This practice applies to storm, potable water, wastewater and industrial pipes, conduits and drainage culverts.1.3 When the specified materials are used in manufacturing the sleeve and installed in accordance with this practice, the sleeve shall extend over a predetermined length of the host pipe as a continuous, tight fitting, corrosion resistant and verifiable non-leaking pipe repaired using one or more pieces of the repair sleeve mechanism. The maximum internal pressure this sleeve can carry depends on the diameter and the wall thickness, ranging from 10 to 15 bars; the external pressure shall not exceed 1.5 bars.1.4 All materials in contact with potable water shall be certified to meet NSF/ANSI 61/372.1.5 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Particular attention is drawn to those safety regulations and requirements involving entering into and working in confined spaces.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 guide is intended to be used in the selection and installation of chemical grout to seal leaks in concrete walls, floors, and ceilings. The procedure described in this guide focuses on the injection of through-wall cracks, but may be adapted to cold joints, control joints, voids associated with penetrations, and other voids contributing to water intrusion through concrete elements. This guide is intended to assist the building owner, owner’s representative, architect, engineer, contractor, or authorized inspector, or combinations thereof, during the selection, specification, or installation, or combinations thereof, of chemical grout for waterproofing repair.4.2 Prior to attempting any repair, it is important for all parties to have a clear and mutual understanding of the limitations of the repair and the iterative nature of the process. Injection of chemical grout does not affect the source of a leak. The repair obstructs the infiltration of water at a specific location only. The flow of water will be diverted elsewhere, and it is common for water to subsequently appear at a different location that was previously dry. A successful campaign at a given location can significantly reduce the amount of water infiltration, but may not fully prevent leakage. Given the nature of the materials and application technique, and depending on the conditions, the repairs should be periodically monitored and additional repair installations may be required.4.3 This guide is applicable to installations at below-grade walls and slabs. At above-grade elements, temperature variation on a daily or seasonal basis may lead to significant or more frequent changes, or both, in the width of a crack or joint. The use of injected chemical grout may be appropriate for many above-grade applications, but this guide does not specifically address installation of grout in dynamic cracks or joints.4.4 Cracks in below-grade walls may be a sign of structural distress. Prior to the injection of chemical grout, the overall conditions and context of the damage should be assessed to determine if a non-structural repair is appropriate.4.5 This guide does not address repairs intended to provide a seal against air leakage or air infiltration.4.6 Project-specific or environmental conditions such as existing construction, prior waterproofing installations, access, water volume or flow rate, water chemistry, temperature, humidity, and other factors may warrant the evaluation of curtain grouting as an alternative to crack injection.4.7 Practices F2304, F2414, and F2454 describe materials and procedures related to the use of chemical grout to seal components of sewer systems. While the specific procedures differ from those described in this guide, the standards contain general information on chemical grouting materials and methods that may be of interest to those involved with waterproofing repair of building elements.4.8 This guide does not address the use of particulate grouts or epoxy as an injection material.1.1 This guide describes the selection of materials, installation methods, and inspection required for sealing leaks at cracks in concrete building walls and slabs using chemical grout. The process discussed in this guide is a waterproofing repair in which voids in a concrete element are sealed with a reactive solution, installed by pressurized injection through drilled or surface-mounted ports.1.2 This guide does not address the use of chemical grout for waterproofing by curtain grouting or injection into preplaced permeable waterstop tubes. Injection of masonry elements presents additional factors beyond the scope of this guide. This guide does not address the use of injectable materials for structural repairs or for geotechnical applications such as soil stabilization.1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.4 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 Typically, FT is used to identify flaws that occur in the manufacture of composite structures, or to identify and track flaws that develop during the service lifetime of the structure. Flaws detected with FT include delamination, disbonds, voids, inclusions, foreign object debris, porosity, or the presence of fluid that is in contact with the backside of the inspection surface. For example, the effect of variable ply number (or thickness), bridging, and an insert simulating delamination on heat flow into a composite is shown in Fig. 1 (left). Bridging (Fig. 1, right) or delaminated areas show up as hot spots due to discontinuous heat flow, causing heating to be localized close to the inspection surface. With dedicated signal processing and the use of representative test samples, characterization of flaw depth and size, or measurement of component thickness and thermal diffusivity, may be performed.FIG. 1 Variation of Heat Flow Into a Composite With Variable Ply Thickness (Scenarios 1, 3, and 4), Bridging (Scenario 2) And an Insert (Scenario 5) (Left), And a Post Layup Line Scan Showing Bright Spots Attributed to Bridging (Right) (Courtesy of NASA Langley Research Center)5.2 Since FT is based on the diffusion of thermal energy from the inspection surface of the specimen to the opposing surface (or the depth plane of interest), the practice requires that data acquisition allows sufficient time for this process to occur, and that at the completion of the acquisition process, the radiated surface temperature signal collected by the IR camera is strong enough to be distinguished from spurious IR contributions from background sources or system noise.5.3 This method is based on accurate detection of changes in the emitted IR energy emanating from the inspection surface during the cooling process. As the emissivity of the inspection surface falls below that of an ideal blackbody (blackbody emissivity = 1), the signal detected by the IR camera may include components that are reflected from the inspection surface. Most composite materials can be examined without special surface preparation. However, it may be necessary to coat low-emissivity, optically translucent inspection surfaces with an optically opaque, high-emissivity water-washable paint.5.4 This practice applies to the detection of flaws with aspect ratio greater than one.5.5 This practice is based on the thermal response of a specimen to a light pulse that is uniformly distributed over the plane of the inspection surface. To ensure that 1-dimensional heat flow from the surface into the sample is the primary cooling mechanism during the data acquisition period, the height and width dimensions of the heated area should be significantly greater than the thickness of the specimen, or the depth plane of interest. To minimize edge effects, the height and width dimensions of the heated area should be at least 5 % greater than the height and width dimensions of the inspection area.5.6 This practice applies to flat panels, or to curved panels where the angle between the line normal to the inspection surface and the IR camera optical axis is less than 30°. Analysis of regions with higher curvature can result in streaking artifacts due to nonuniform heating (Fig. 2).FIG. 2 Thermal Scan of a Complex Composite Shape (Left) Showing Less Effective Heating of a High Curvature Saddle-Region, Resulting in a Darker Diagonal Streak in the Thermographic Image (Right) (Courtesy of NASA Langley Research Center)1.1 This practice describes a procedure for detecting subsurface flaws in composite panels and repair patches using Flash Thermography (FT), in which an infrared (IR) camera is used to detect anomalous cooling behavior of a sample surface after it has been heated with a spatially uniform light pulse from a flash lamp array.1.2 This practice describes established FT test methods that are currently used by industry, and have demonstrated utility in quality assurance of composite structures during post-manufacturing and in-service examinations.1.3 This practice has utility for testing of polymer composite panels and repair patches containing, but not limited to, bismaleimide, epoxy, phenolic, poly(amide imide), polybenzimidazole, polyester (thermosetting and thermoplastic), poly(ether ether ketone), poly(ether imide), polyimide (thermosetting and thermoplastic), poly(phenylene sulfide), or polysulfone matrices; and alumina, aramid, boron, carbon, glass, quartz, or silicon carbide fibers. Typical as-fabricated geometries include uniaxial, cross ply, and angle ply laminates; as well as honeycomb core sandwich core materials.1.4 This practice has utility for testing of ceramic matrix composite panels containing, but not limited to, silicon carbide, silicon nitride, and carbon matrix and fibers.1.5 This practice applies to polymer or ceramic matrix composite structures with inspection surfaces that are sufficiently optically opaque to absorb incident light, and that have sufficient emissivity to allow monitoring of the surface temperature with an IR camera. Excessively thick samples, or samples with low thermal diffusivities, require long acquisition periods and yield weak signals approaching background and noise levels, and may be impractical for this technique.1.6 This practice applies to detection of flaws in a composite panel or repair patch, or at the bonded interface between the panel and a supporting sandwich core or solid substrate. It does not apply to discontinuities in the sandwich core, or at the interface between the sandwich core and a second panel on the far side of the core (with respect to the inspection apparatus).1.7 This practice does not specify accept-reject criteria and is not intended to be used as a basis for approving composite structures for service.1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 Full-encirclement-type band clamps are recommended for repairs only where the pipe is able to maintain its structural integrity. These clamps are not recommended for permanent repair of pipe where the damage could propagate outside the clamp under anticipated field conditions (see 5.1.1 for repair limitations). In such situations, it is recommended to cut out and replace the damaged pipe with a new piece. Clamps that are used for repair should comply with the manufacturer’s specifications for use and the manufacturer’s installation instructions should be followed.4.2 These clamps may be used to cover holes left in the pipe from abandoned service line connections, purge points, and accidental punctures.4.3 These clamps may be used to reinforce the pipe where the wall thickness has been reduced because of gouges or other irregularities.4.4 Some users reinforce polyethylene pipe after it has been squeezed-off as a precaution against pipe damage that may have occurred during the squeeze-off process and as a means of ensuring that the pipe will not be squeezed-off again at the same location. Consult with the polyethylene pipe manufacturer as to the appropriateness of squeeze-off for their product, and for circumstances when reinforcement is recommended. See Guide F1041.1.1 This guide specifically addresses the design and installation of full-encirclement-type band clamps for repair of gouges, punctures, or holes, and for reinforcement of polyethylene plastic pipe. Guidelines are provided for selecting and using clamps in pipe sizes 2 in. nominal (60 mm) and larger.1.1.1 A test method is also provided for the user to assess the applicability of the repair clamp. Under appropriate circumstances, this type of clamp offers a convenient, effective, and safe means of restoring the integrity of an in-service pipeline, without cutting out a section of pipe (see Note 1). The pipe to be repaired cannot be backed by a stiffener for internal support and cross-sectional dimensional control. Satisfactory use of this type of clamp should rely on the crush resistance of the pipe itself and a fitting design concept, which retains the cross-sectional pipe configuration while minimizing compressive forces required to obtain an effective leakage seal.NOTE 1: The appropriateness for use of this type of clamp should be determined by using the information contained in this guide and from consultation with, and recommendations of, both the pipe and clamp manufacturers. The basic premise for use of this type of clamp is that it is recommended by the manufacturer for this specific application and that step-by-step installation instructions are available for that application. It is important in the development of this type of clamp that prototype testing be conducted to evaluate performance expectations because of the physical limitations encountered when designing it for use with plastic pipe.1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, 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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Injuries to tendons or ligaments are frequently treated by surgery to repair the damaged tissues and facilitate the healing process. The potential of TEMPs to enhance the outcomes (including function, pain, anatomy) of the surgical repair has been recognized.Examples of tissues that when injured may be appropriate for repair using TEMPs: rotator cuff with a partial or full tear; Achilles tendon; Achilles tendon after harvesting for anterior cruciate ligament repair; patella tendon; patella tendon after harvesting for anterior cruciate ligament repair; quadriceps tendon; posterior cruciate ligament; medial collateral ligaments; lateral collateral ligaments; flexor tendons.TEMPs may be used with the intent to improve the surgical outcome of tendon or ligament repair by (a) assuming some of the mechanical load experienced at the repair site to stabilize the surgical repair, (b) improving the natural biological healing process, or (c) a combination of these mechanisms.TEMPs should improve clinical outcome. This may be accomplished by reducing or eliminating pain, returning function, shortening the recovery time following surgery, facilitating early mobility, improving return of strength, improving mobility, or other clinically relevant parameters.The mechanism used by TEMPs to improve surgical repair should be understood and this conclusion should be supported by experimental results and should be supportive of the primary function of the TEMP.TEMPs with the primary function of mechanical reinforcement may also have a secondary, biological function.When the product is used to improve the body’s natural biological repair process of tendons or ligaments, the product should allow cell attachment, migration, infiltration, extracellular matrix deposition and organization, formation of tendon or ligament repair tissue, integration with adjacent tendon, ligament or bone, tendon-bone attachment, or more than one of these actions.When the TEMP is used to provide a mechanical support of the surgical repair of a tendon or ligament, the product may provide enhanced mechanical properties of the repaired construct immediately after the surgery. Ideally, TEMPs would have mechanical properties similar to the uninjured native tissue being repaired. After surgery, the TEMP should limit the amount of tendon/ligament separation from the bone, or separation of the fractured ends of the tendon or ligament, or reduce the number of patients that have these as outcomes of the surgery. The TEMP may allow functionality to return to the repaired tendon or ligament in a shorter time than without the use of the product.1.1 This guide is intended as a resource for individuals and organizations involved in the development, production, and delivery of tissue engineered medical products (TEMPs) intended to provide a mechanical (functional) reinforcement of the surgical repair of tendons and ligaments.1.2 Surgical repair can include procedures that repair tendon to tendon, tendon to bone, tendon to muscle, ligament to ligament, and ligament to bone. In the context of this guide, a tendon is a fibrous cord or band that connects a muscle to a bone or other structure and consists of both dense collagenous fibers and rows of elongated tendon cells. In contrast, a ligament is a band or sheet of fibrous tissue connecting two or more bones, or cartilagenous structures.1.3 Examples of TEMPs for use in reinforcement of tendon or ligament repairs include extracellular matrices (including allograft tissue, xenograft tissue, and tissue engineered extracellular matrix), polymeric matrices, membranes, or combinations of two or more of these, with or without cells and/or molecular mediators, where the function is to reinforce the surgical repair of tendon to tendon, tendon to bone, tendon to muscle, ligament to ligament, or ligament to bone.1.4 The products may be rapidly degrading, slowly degrading, or non-degrading.1.5 The guide is not intended to apply to TEMPs that have a primary function to induce a biological repair through cell or molecular action, although biologic activity may be a feature of the TEMPs. Examples of products or product concepts that are not included are (a) growth factors or cytokines applied to a biologic or synthetic scaffold, and (b) platelet-enriched plasma applied to or within a biologic or polymeric scaffold, where the primary function of the product is biologic.1.6 The guide is not intended to apply to TEMPs that have a primary function to induce a chemical repair. An example of a product or product concept that would not be included would be a polymeric matrix containing reagents that glue collagenous tissues together.1.7 The guide is not intended to apply to TEMPs that are designed to be used to achieve primary surgical repair of injured tendons and ligaments.1.8 The guide is not intended to apply to TEMPs that are designed to replace tendons or ligaments.1.9 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.10 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

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4.1 This practice is for use by designers and specifiers, regulatory agencies, owners, and inspection organizations who are involved in the rehabilitation of pipes through the use of a resin-impregnated tube installed within a damaged existing host pipe. As for any practice, modifications may be required for specific job conditions.1.1 This practice covers requirements and test methods for the sectional cured-in-place lining (SCIPL) repair of a pipe line (4 in. through 60 in. (10.2 cm through 152 cm)) by the installation of a continuous resin-impregnated-textile tube into an existing host pipe by means of air or water inversion and inflation. The tube is pressed against the host pipe by air or water pressure and held in place until the thermoset resins have cured. When cured, the sectional liner shall extend over a predetermined length of the host pipe as a continuous, one piece, tight fitting, corrosion resistant, and verifiable non-leaking cured-in-place pipe.1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.3 There is no similar or equivalent ISO Standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 This practice is for use by designers and specifiers, regulatory agencies, owners, and inspection organizations who are involved in the rehabilitation of gravity flow, non-pressure pipes through the use of a resin-saturated liner installed within a section of damaged or leaking existing pipe. As for any practice, modifications may be required for specific job conditions.1.1 This practice describes the procedures for the sectional repair of gravity flow, non-pressure pipelines and conduits 3 in. to 60 in. (75 mm to 1500 mm) diameter by the installation of a resin-saturated liner which is placed onto or wrapped around a carrier device, pushed or pulled into an existing pipeline or conduit and expanded against the interior of the host pipe or conduit with air pressure. The resin is cured under ambient conditions, by photoinitiated reaction or with the application of heat. When cured, the finished sectional repair will be tight-fitting across its installed length. This repair process is used in a variety of gravity flow, non-pressure applications such as sanitary sewers, storm sewers, drains, electrical conduits and ventilation systems.1.2 Units—The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.3 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 Injuries to the knee meniscus are one of the most common orthopaedic problems. Meniscus injures include acute tears (such as occur in sports injuries), chronic degenerative tears, extrusion/subluxation, and/or degenerative dysfunction that occurs as part of the knee aging process or as a result of multiple meniscus surgeries. Knee arthroscopy for partial excision of the knee meniscus (partial meniscectomy) is the most commonly performed orthopaedic procedure.5.2 Complete or near complete excision of the meniscus in a young individual is associated with an early increased risk of knee osteoarthritis due to the loss of the meniscus chondroprotective effects. Lateral meniscal injuries tend to be more severe than medial injuries. Meniscus repair, augmentation, transplantation, and/or reconstruction is recommended in individuals to restore the chondroprotective effect of the meniscus, relieve pain, and prevent degenerative knee osteoarthritis. The potential of TEMPs to enhance the outcome of the surgical meniscus repair and/or reconstruction has been recognized.5.3 The knee joint and temporomandibular joint (TMJ) are examples of joints with meniscal structures.5.4 TEMPS may be used with the intent of enhancing the surgical outcome by improving the biological repair at the site of implantation, by providing mechanical function at a defect site, or by a combination of these mechanisms.5.5 Improving surgical outcome may include improving function relative to the pre-operative condition, shortening the recovery time after surgery, relieving pain, enabling return to normal daily activities, encouraging tissue growth into the defect site, restoring the mechanical function of the meniscus, delaying the progression of osteoarthritis, or any combination thereof.1.1 This guide is intended as a resource for individuals and organizations involved in the production, delivery, and regulation of tissue engineered medical products (TEMPs) and other tissues intended for use in the surgical repair, replacement, and/or reconstruction of the knee meniscus.1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.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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ASTM C1722-23 Standard Guide for Repair and Restoration of Dimension Stone Active 发布日期 :  1970-01-01 实施日期 : 

4.1 The purpose of this guide is to assist those who wish to restore facades constructed of or finished with dimension stone. It is an aid to owners, building managers, architects, engineers, contractors and others involved with restoring dimension stone.4.2 This guide is not meant to supersede manufacturers' directions and recommendations for the use of their specific products, or written directions from the architect or building owner. When manufacturers' directions are in conflict with this guide, follow their recommendations or consult with their technical staff for further direction.4.3 Prior to undertaking a full-scale repair or cleaning procedure, the methods under consideration for repair, patching or cleaning should be tested on an area not easily visible or on sample stones. The test will assist in judging the effectiveness of the chosen method and permit assessment of potential damage to the building stone. Completely evaluate the success of the sample repairs before undertaking the full-scale cleaning or repair procedure.1.1 This guide describes materials and procedures for restoring facades constructed of or finished with dimension stone. All of the materials, procedures, and principles are suitable for restoration of historic and nonhistosric structures.1.2 This guide is not intended to address restoration of interior dimension stone, although many of the materials and procedures may be suitable for interior use.1.3 Units—The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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This practice covers the repair of rigid cellular polyurethane insulation systems on outdoor service vessels operating within a specified temperature range. Before any repairs are performed, all damaged nonadhering foam should be removed up to the dry, solidly adhering layer and the remaining foam insulation should then be beveled on all sides. If the existing substrate primer is damaged, it should be wire-brushed and reprimed where feasible. To protect the surrounding undamaged area, a covering should be installed around the area that needs to be repaired prior to the application of spray foam. Repairs shall be made in accordance with the prescribed procedure.1.1 This practice covers the repair of spray-applied polyurethane insulation on vessels normally operating at temperatures between −30 and +107°C [−22 and +225°F].1.2 Warning—At temperatures below 0°C [32°F] the application of a spray “foam” directly onto the cold substrate may not be possible. The term “foam” applies to spray-applied polyurethane or polyisocyanurate (PUR or PIR) rigid cellular plastic only, and not to any other plastic insulation.1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system 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.1.4 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. For a specific precautionary statement see 1.2.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 The inhalation of airborne asbestos fibers has been shown to cause asbestosis, lung cancer, and mesothelioma.5.1.1 The U.S. Environmental Protection Agency reports that “Effects on the lung are a major health concern from asbestos, as chronic (long-term) exposure to asbestos in humans via inhalation can result in a lung disease termed asbestosis. Asbestosis is characterized by shortness of breath and cough and may lead to severe impairment of respiratory function. Cancer is also a major concern from asbestos exposure, as inhalation exposure can cause lung cancer and mesothelioma (a rare cancer of the thin membranes lining the abdominal cavity and surrounding internal organs), and possibly gastrointestinal cancers in humans. EPA has classified asbestos as a Group A, known human carcinogen” (1).45.1.2 The World Health Organization states: “Exposure to asbestos occurs through inhalation of fibres primarily from contaminated air in the working environment, as well as from ambient air in the vicinity of point sources, or indoor air in housing and buildings containing friable asbestos materials. The highest levels of exposure occur during repackaging of asbestos containers, mixing with other raw materials and dry cutting of asbestos-containing products with abrasive tools” (2).5.1.3 The World Bank states: “Health hazards from breathing asbestos dust include asbestosis, a lung scarring disease, and various forms of cancer (including lung cancer and mesothelioma of the pleura and peritoneum). These diseases usually arise decades after the onset of asbestos exposure. Mesothelioma, a signal tumor for asbestos exposure, occurs among workers’ family members from dust on the workers’ clothes and among neighbors of asbestos air pollution point sources” (3).5.2 Extensive litigation has occurred worldwide as a result of the health effects of asbestos over the past century, resulting in considerable economic consequences. The regulatory response to asbestos hazards has resulted in civil sanctions and criminal prosecution of violators.5.3 Regarding the production and use of asbestos fiber:5.3.1 The U.S. Geological Survey (USGS) reports: “World consumption was relatively steady between 2003 and 2007, averaging 2.11 million metric tons (Mt). The leading consuming countries in 2007 were, in decreasing order tonnage, China (30 %), India (15 %), Russia (13 %), Kazakhstan and Brazil (5 % each), and Thailand, Uzbekistan, and Ukraine (4 % each). These eight countries accounted for about 80 % of world asbestos consumption in 2007. From 2003 through 2007, apparent consumption declined in most countries. However, there were significant increases in apparent consumption in China, India, and Uzbekistan between 2003 and 2007. In general, world asbestos consumption is likely to decline as more countries institute bans on its use” (4).5.3.2 The World Health Organization also states: “Bearing in mind that there is no evidence for a threshold for the carcinogenic effect of asbestos and the increased cancer risks have been observed in populations exposed to very low levels, the most efficient way to eliminate asbestos-related diseases is to stop using all types of asbestos. Continued use of asbestos-cement in the construction industry is of particular concern, because the workforce is large, it is difficult to control exposure, and in-place materials have the potential to deteriorate and pose a risk to those carrying out alterations, maintenance, and demolition” (2).5.3.3 The Chrysotile (formerly Asbestos) Institute reports that: “More than 90 % of the world production of chrysotile is used in the manufacture of chrysotile-cement, in the form of pipes, sheets, and shingles. These products are used in some sixty industrialized and developing countries” (5).5.4 It follows that the installed base of asbestos-cement products worldwide is enormous and continues to grow. In other words, the problem of exposure to asbestos fibers from working with these materials is substantial and will remain significant for the foreseeable future.5.5 The significance of this practice is that it provides work practices that protect worker and community health within the resources available in developing as well as industrialized countries. It relies as much as possible on tools, equipment, and supplies that are readily available without recourse to specialty suppliers. The techniques require careful and diligent workmanship but do not require the services of highly-skilled tradesmen.5.6 This practice is intended to be used not only by construction workers and tradesmen in the performance of their work, but also by building owners and others as the basis for preparing contracts and tenders for activities included in the scope of this practice. It will also provide a foundation for government officials to develop regulations intended to protect worker and community health. Where such regulations already exist, of necessity they take precedence over this practice in event of a conflict.5.7 The persons who are most at risk of exposure to airborne asbestos fibers are those who perform work on asbestos-cement products during maintenance, renovation, and repair operations. This practice places its primary emphasis on the protection of their health. However, other members of the community—other workers and individuals in a building being renovated, residents of a house undergoing repairs, and unsuspecting bystanders—are at risk to a lesser degree. By minimizing the risk to the worker performing the maintenance, renovation, and repair operations, the potential exposure of others is reduced as well.5.8 It is expected that employers will comply voluntarily with the provisions of this practice in the interest of protecting worker and community health and reducing their own liability. However, the existence of a regulatory infrastructure for occupational and community health greatly enhances compliance with measures to reduce exposure to asbestos fibers and other toxic materials. In some countries, such a system is highly advanced, but in others it needs to be created or further developed. These efforts can be furthered by referencing this practice in laws and regulations and requiring compliance with its provisions.5.8.1 Issuance of construction permits can be made contingent on showing evidence of worker training, experience in the use of these procedures, and adequate resources (manpower, equipment, and supplies) to use them properly.5.8.2 A contractual framework that references this practice and requires use of its procedures ensures the building owner or other party securing construction services under a contract or tender arrangement that the responding offeror has been informed as to the expected level of performance when working with asbestos-cement products.1.1 This practice describes work practices for asbestos-cement products when maintenance, renovation, and repair are required. This includes common tasks such as drilling and cutting holes in roofing, siding, pipes, etc. that can result in exposure to asbestos fibers if not done carefully. These work practices are supplemented and facilitated by the regulatory, contractual, training, and supervisory provisions of this practice.1.2 Materials covered include those installed in or on buildings and facilities and those used in external infrastructure such as water, wastewater, and electrical distribution systems. Also included is pavement made from asbestos-cement manufacturing waste.1.3 The work practices described herein are intended for use only with asbestos-cement products already installed in buildings, facilities, and external infrastructure. They are not intended for use in construction or renovation involving the installation of new asbestos-cement products.1.4 The work practices are primarily intended to be used in situations where small amounts of asbestos-cement products must be removed or disturbed in order to perform maintenance, renovation, or repair necessary for operation of the building, facility, or infrastructure.1.5 The work practices described herein are also applicable for use where the primary objective is the removal of asbestos-cement products from the building or other location, particularly the use of wet methods and other means of dust and fiber control.1.6 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.7 Warning—Asbestos fibers are acknowledged carcinogens. Breathing asbestos fibers can result in disease of the lungs including asbestosis, lung cancer, and mesothelioma. Precautions in this practice should be taken to avoid creating and breathing airborne asbestos particles from materials known or suspected to contain asbestos. Comply with all applicable regulatory requirements addressing asbestos.1.8 This practice does not address safety hazards associated with working on asbestos-cement products such as falling through roof panels or trench cave-ins. The use of power tools presents possible electrical hazards, particularly in wet environments. These and other safety hazards must be considered and controlled in compliance with the employer’s policies and applicable regulations.1.9 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.1.10 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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