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4.1 Sensitivity and vulnerability methods can be applied to a variety of hydrogeologic settings, whether or not they contain specifically identified aquifers. However, some methods are best suited to assess groundwater within aquifers, while others assess groundwater above aquifers or groundwater in areas where aquifers have not been identified.4.1.1 Intergranular media systems, including alluvium and terrace deposits, valley fill aquifers, glacial outwash, sandstones, and unconsolidated coastal plain sediments are characterized by intergranular flow, and thus generally exhibit slower and more predictable groundwater velocities and directions than in fractured media. Such settings are amenable to assessment by the methods described in this guide. Hydrologic settings dominated by fracture flow or flow in solution openings are generally not amenable to such assessments, and application of these techniques to such settings may provide misleading or totally erroneous results.4.2 The methods discussed in this guide provide users with information for making land- and water-use management decisions based on the relative sensitivity or vulnerability of underlying groundwater or aquifers to contamination. Most sensitivity and vulnerability assessment methods are designed to evaluate broad regional areas for purposes of assisting federal, state, and local officials to identify and prioritize areas where more detailed assessments are warranted, to design and locate monitoring systems, and to help develop optimum groundwater management, use and protection policies. However, some of these methods are independent of the size of the area evaluated and, therefore, can be used to evaluate the aquifer sensitivity and vulnerability of a specific area.4.3 Many methods for assessing groundwater sensitivity and vulnerability require information on soils, and for some types of potential groundwater contaminants, soil is the most important factor affecting contaminant movement and attenuation from the land surface to groundwater. The relatively large surface area of the clay-size particles in most soils and the soils' content of organic matter provide sites for the retardation and degradation of contaminants. Unfortunately, there are significant differences in the definition of soil between the sciences of hydrogeology, engineering, and agronomy. For the purposes of this guide, soils are considered to be those unconsolidated organic materials and solid mineral particles that have been derived from weathering and are characterized by significant biological activity. These typically include unconsolidated materials that occur to a depth of 2 to 3 m or more.4.3.1 In many areas, significant thicknesses of unconsolidated materials may occur below the soil. Retardation, degradation, and other chemical attenuation processes are typically less than in the upper soil horizons. These underlying materials may be the result of depositional processes or may have formed in place by long-term weathering processes with only limited biological activity. Therefore, when compiling the data required for assessing groundwater sensitivity and vulnerability, it is important to distinguish between the soil zone and the underlying sediments and to recognize that the two zones have significantly different hydraulic and attenuation properties.1.1 This guide covers information needed to select one or more methods for assessing the sensitivity of groundwater or aquifers and the vulnerability of groundwater or aquifers to water-quality degradation by specific contaminants.1.2 This guide may not be all-inclusive; it offers a series of options and does not specify a course of action. It should not be used as the sole criterion or basis of comparison, and does not replace professional judgment.1.3 This guide is to be used for evaluating sensitivity and vulnerability methods for purposes of land-use management, water-use management, groundwater protection, government regulation, and education. This guide incorporates descriptions of general classes of methods and selected examples within these classes but does not advocate a particular method.1.4 Limitations—The utility and reliability of the methods described in this guide depend on the availability, nature, and quality of the data used for the assessment; the skill, knowledge, and judgment of the individuals selecting the method; the size of the site or region under investigation; and the intended scale of resulting map products. Because these methods are being continually developed and modified, the results should be used with caution. These techniques, whether or not they provide a specific numeric value, provide a relative ranking and assessment of sensitivity or vulnerability. However, a relatively low sensitivity or vulnerability for an area does not preclude the possibility of contamination, nor does a high sensitivity or vulnerability necessarily mean that groundwater or an aquifer is contaminated.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 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.1.6.1 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 analytical methods for engineering design.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.1.8 This guide offers an organized collection of information or a series of options and does not recommend a specific course of action. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of this guide 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.

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4.1 If a coating is to fulfill its function of protecting or imparting unique properties to the surface of a substrate, it must adhere to the substrate for the expected service life. Because surface preparation (or lack of it) has a drastic effect on adhesion of coatings, a test method for evaluating adhesion to different surface treatments or of different coatings to the same treatment is of considerable use to the industry.4.2 The limitations of all adhesion methods, and the specific limitation of this test method to lower levels of adhesion (see 1.3) should be recognized before using it. These test methods are mechanized adaptations of Test Methods D3359; therefore, the intra- and interlaboratory precision of these test methods are similar to Test Methods D3359 and to other widely-accepted tests for coated substrates, for example, Test Method D2370, but this is partly the result of it being insensitive to all but large differences in adhesion. The pass-fail scale of 0 to 5 for Method B1 and B2 was selected deliberately to avoid a false impression of being sensitive.1.1 These test methods describe procedures for assessing the adhesion of metallic and inorganic coatings and other thin films to metallic and nonmetallic substrates. Assessment is made by applying pressure-sensitive tape to a coated surface and then utilizing a mechanical device to remove the tape at a regulated, uniform rate and constant angle while simultaneously recording the removal force.1.2 Four methods are described. Methods A1 and A2 are intended primarily for use on parts. Methods B1 and B2 are intended primarily for use in laboratory evaluations. Methods B1 and B2 are not recommended for testing coatings and films on polymer substrates.1.3 These test methods may be used to establish whether the adhesion of a coating to a substrate is within a required range (between a quantified low and a quantified high level). Determination of actual adhesive forces requires more sophisticated methods of measurement. In multilayer systems adhesion failure may occur between intermediate coating layers so that the adhesion of the total coating system to the substrate may not necessarily be determined.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 This guide is designed to assist medical device manufacturers as they develop new devices or qualify existing devices (e.g., catheters, needles) for delivering clinical cell therapies. Cytocompatibility considers the impact of the delivery device on the cells passing through the device during the delivery procedure. The biological safety of the device (e.g., the device’s cytotoxicity) should be addressed via other methods, such as ISO 10993-5. It is understood that this guide does not address testing of specific cellular products with specific delivery devices. Such testing may be required by regulatory authorities prior to clinical trial of cellular product or marketing applications. This guide outlines considerations to make the product qualification procedures more likely to succeed and more cost effective.4.2 The key aspects of assessing device cytocompatibility include selecting a test cell line or cell lines and determining the cell physiology parameters that will be measured to make a determination of cytocompatibility. Acceptance criteria for designating a device as cytocompatible are not detailed here. It will be up to the delivery device end user to determine if the results of a cytocompatibility assessment are sufficient to consider that device cytocompatible. Delivery device lot to lot variability may impact cytocompatibility, therefore validated manufacturing processes should be considered when producing devices for cytocompatibility assessments.1.1 This guide outlines the parameters to consider when designing in vitro tests to assess the potential impact of a delivery device on a cellular product being dispensed. This guide does not provide specific protocols, but rather suggests what should be considered the minimum characterization necessary to assess device cytocompatibility. Topics discussed include selecting an appropriate cell line(s), cell physiology parameters to measure, and relevant test procedure variables. Only cells suspended in liquid and infused through a device are considered. Cell therapies paired with scaffolds, suspended in hydrogels, or administered via other methods (e.g., tissue grafting) are not included in the scope of this document. This document does not address physical characterization of delivery devices, such as mechanics, composition, or degradation.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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