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5.1 The enterococci are indicators of the bacteriological quality for potable water, shellfish growing waters, ambient, and recreational waters. A direct relationship between swimming, associated gastroenteritis, and enterococci has been established through epidemiological studies and marine and fresh water bathing beaches. These studies have led to the development of criteria that can be used to establish bathing water standards based on established health-water quality relationships.5.2 Since small or large volumes of water or dilutions thereof, can be analyzed by the membrane filter technique, a wide range of levels of enterococci in water can be enumerated and detected.1.1 This test method covers a membrane filter (MF) procedure for the detection and enumeration of the enterococci bacteria in water. The enterococci, which include Entero-coccus faecalis (E. faecalis), E. faecium, and their varieties are commonly found in the feces of humans and other warm-blooded animals. Although some strains are ubiquitous and not related to fecal pollution, enterococci in water are an indication of fecal pollution and the possible presence of enteric pathogens. These bacteria are found in water and wastewater in a wide range of densities. The detection limit is one colony forming unit (CFU)/volume filtered.1.2 This test method has been used successfully with temperate fresh and marine ambient waters, and wastewaters. It is the user’s responsibility to ensure the validity of this test method for waters of untested types.1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are included 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. For specific hazard statements, see Section 9.1.5 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 Characterizing tack for different prepreg materials, test parameters, surface combinations, and environmental conditions provides insight for optimizing process parameters (particularly deposition rate and deposition temperature) for industrial automated material placement processes.5.2 Results obtained through employing the continuous application-and-peel method, as described in studies (1-3),3 reflect the effects of adhesion forming between prepreg layers or between prepreg and metal substrate, and loss of cohesion within the resin in the prepreg, upon tack. This test method allows the adhesive properties of B-staged resin to be explored in a manner relevant for dynamic material deposition processes, where timescales for bonding of prepreg to the substrate or previously placed prepreg layers are short prior to curing. In contrast, Test Methods D3167 and D1781 determine the peel resistance of adhesive bonds for adhesion measurement and process control of laminated or bonded adherends.5.3 The test method is suitable to quantify tack of prepregs for acceptance and process control and can be extended to determine resin shelf life or to adjust process parameters to resin out-time. Direct comparison of different resins/prepreg or processes can only be made when specimen preparation and test conditions are identical.1.1 This test method covers measurement of adhesion (tack) between partially cured (B-staged) composite prepreg and a substrate in a peel test, under specified conditions. The test may be conducted to measure tack between a flexible layer of prepreg and another prepreg layer bonded to a rigid substrate (Method I) or a rigid metal substrate (Method II). This test method is primarily geared towards material characterization for automated material layup but can be modified for use with other processes. It is well known that material tack is a function of multiple processing and environmental variables. Permissible composite prepreg materials include carbon, glass, and aramid fibers within a B-staged thermoset resin.1.2 Measured tack is specified in terms of a peel force at a given specimen width.1.3 Units—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.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 This test method is useful for measuring recreational water quality and chlorinated wastewaters, although it can be used for any water suspected of contamination by fecal wastes of warm-blooded animals. The significance of finding E. coli in recreational water samples, especially samples obtained from fresh recreational waters, is that there is a risk of gastrointestinal illness, directly related to the E. coli density, associated with swimming.55.2 Since small or large volumes of water or dilutions thereof can be analyzed by the MF technique, a wider range of levels of E. coli in water can be detected and enumerated than with other methods.1.1 This test method describes a membrane filter (MF) procedure for the detection and enumeration of Escherichia coli, a bacterium found exclusively in the feces of humans and other warm-blooded animals. The presence of these microorganisms in water is an indication of fecal pollution and the possible presence of enteric pathogens. These bacteria are found in water and wastewater in a wide range of densities. The detection limit of this procedure is one colony forming unit (CFU) per volume filtered.1.2 This test method has been used successfully with temperate fresh and marine ambient waters, and wastewaters. It is the user’s responsibility to ensure the validity of this test method for waters of other types.1.3 The values stated in SI units are to be regarded as 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. For specific hazard statements, see Section 9.1.5 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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