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1.1 This practice covers requirements for defining, testing, and verifying the performance of high performance liquid chromatographic (HPLC) systems when used for trace analysis of pesticides and toxic substancesin carrying out pollution control programs and in assessing the quality of food products as mandated by national laws and regulations. As a practical matter, this practice is intended to cover requirements of reversed-phase (adsorption) HPLC systems. Microbore column and ion-exchange column HPLC systems are not covered here. It is not intended to exclude any other equivalent means of analysis. An HPLC system can successfully be applied in the analysis of a variety of sample types including ground and surface water, municipal and industrial effluents, workplace air, soils and sediments, plant abd animal tissue, and food products. Collection and extraction techniques , appropriate to the sample type, are required prior to analysis. Sampling techniques and measurement methods are not covered in this recommendation; however, some relevant measurement methods may be found in references listed in Appendix X1.

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1.1 This test method covers the ability of gasoline-alcohol blends to retain water in solution or in a stable suspension at the lowest temperature to which they are likely to be stored or exposed in use.1.2 This test method is intended to measure the temperature at which a gasoline-alcohol blend separates into two distinct phases in accordance with the criteria defined in this test method. Samples that form a haze are considered not to have phase separated.1.3 This test method is applicable to gasoline-alcohol blends for use as fuels in spark-ignition engines that contain saturated C1 to C4 alcohols only. The test method does not apply to fuels that contain an alcohol as the primary component, such as M85 or Ed85, or to gasoline-ether blends.1.4 The values stated in SI units are the standard, except when other units are specified by federal regulation. Values given in parentheses are provided for informational purposes.1.5 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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The threshold temperature measured by this test method is an indication of the thermal instability of a chemical or mixture of chemicals, qualitatively expressed by the temperature rise. There is a potential hazard whenever the temperature of the chemical exceeds the threshold temperature unless proper design safeguards are utilized. This does not imply that temperatures lower than the threshold temperature are safe. Since this test is not an adiabatic type and does not indicate the effect of mass or time, other testing would be needed to characterize the use or storage of the chemical at lower temperatures.Because of rate and mass dependent factors, failure to find evidence of an exothermic reaction does not ensure thermal stability unless substantiated by other test methods.1.1 This test method is designed to determine the temperature at which a chemical or mixture of chemicals, confined initially as a solid or liquid in air or other controlled atmosphere under normal laboratory conditions, will start a reaction, generating appreciable heat when subjected to a programmed temperature increase. This test method is also designed to measure the magnitude and rate of heat generation.1.2 This test method is for use with condensed phases.1.3 This test method can be used over a temperature range from 0 to 500oC, and a pressure range of 0 to 5000 psi.1.4 As with any thermal stability test, proper safety precautions should be instituted to protect personnel. See also Section 6.1.5 Limitations1.5.1 The threshold temperature determined by this method may be higher than one determined by heating at a lesser rate.1.5.2 Samples of the same material having different thermal histories may have different threshold temperatures.1.6 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety problems 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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The SCCW may be present in the workplace atmosphere where these materials are manufactured, processed, transported, or used. This test method can be used to monitor airborne concentrations of fibers in these environments. It may be employed as part of a personal or area monitoring strategy.This test method is based on dimensional considerations only. As such, it does not provide a positive identification of the fibers counted. Analysis by SEM or TEM is required when additional fiber identification information is needed.Note 1—This test method assumes that the analyst is familiar with the operation of PCM instrumentation and the interpretation of data obtained using this technique.This test method is not appropriate for measurement of fibers with diameters less than approximately 0.25 μm due to visibility limitations associated with PCM. The SEM or TEM methods may be used to provide additional size information of SCCW if needed (refer to Practice D6058 for additional information on the use of these methods).Results from the use of this test method shall be reported along with 95 % confidence limits for the samples being studied. Individual laboratories shall determine their intralaboratory coefficient of variation and use it for reporting 95 % confidence limits (1,3,4).1.1 This test method covers the sampling methods and analysis techniques used to assess the airborne concentration of single-crystal ceramic whiskers (SCCW), such as silicon carbide and silicon nitride, which may occur in and around the workplace where these materials are manufactured, processed, transported, or used. This test method is based on the collection of fibers by filtration of a known quantity of air through a filter. The filter is subsequently evaluated with a phase contrast microscope (PCM) for the number of fibers meeting appropriately selected counting criteria. This test method cannot distinguish among different types of fibers. This test method may be appropriate for other man-made mineral fibers (MMMF).1.2 This test method is applicable to the quantitation of fibers on a collection filter that are greater than 5 μm in length, less than 3 μm in width, and have an aspect ratio equal to or greater than 5:1. The data are directly convertible to a statement of concentration per unit volume of air sampled. This test method is limited by the diameter of the fibers visible by PCM (typically greater than 0.25 μm in width) and the amount and type of coincident interference particles.1.3 A more definitive analysis may be necessary to confirm the identity and dimensions of the fibers located with the PCM, especially where other fiber types may be present. Such techniques may include scanning electron microscopy (SEM) or transmission electron microscopy (TEM). The use of these test methods for the identification and size determination of SCCW is described in Practice D6058 and Test Methods D6059 and D6056.1.4 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 and health practices and determine the applicability of regulatory limitations prior to use.

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5.1 Users of this practice must determine for themselves whether the practices described meet the requirements of local or national authorities regulating asbestos or other fibrous hazards.5.2 Variations of this practice have been described by the Asbestos Research Council in Great Britain (8), the Asbestos International Association (AIA) (RTM 1) (9), NIOSH 7400, OSHA (Reference Method ID 160), and ISO 8672. Where the counting rules of these methods differ, this is noted in the text.5.3 Advantages5.3.1 The technique is specific for fibers. PCM is a fiber counting technique that excludes non-fibrous particles from the analysis.5.3.2 The technique is inexpensive, but requires specialized knowledge to carry out the analysis for total fiber counts, at least in so far as the analyst is often required under regulations to have taken a specific training course (for example, NIOSH 582, or equivalent).5.3.3 The analysis is quick and can be performed on-site for rapid determination of the concentrations of airborne fibers.5.3.4 The procedure provides for a discriminate counting technique that can be used to estimate the percentage of counted fibers that may be asbestos.5.4 Limitations5.4.1 The main limitation of PCM is that fibers are not identified. All fibers within the specified dimensional range are counted. Differential fiber counting may sometimes be used to discriminate between asbestos fibers and fibers of obviously different morphology, such as cellulose and glass fiber. In most situations, differential fiber counting cannot be used to adequately differentiate asbestos from non-asbestos fibers for purposes of compliance with regulations without additional positive identification. If positive identification of asbestos is required, this must be performed by polarized light or electron microscopy techniques, using a different portion of the filter.5.4.2 A further limitation is that the smallest fibers visible by PCM are about 0.2 µm in diameter, while the finest asbestos fibers may be as small as 0.02 µm in diameter.5.4.3 Where calculation of fiber concentration provides a result exceeding the regulatory standard, non-compliance is assumed unless it can be proven that the fibers counted do not belong to a member or members of the group of fibers regulated by that standard.1.1 This practice2 describes the determination of the concentration of fibers, expressed as the number of such fibers per millilitre of air, using phase contrast microscopy and optionally transmission electron microscopy to evaluate particulate material collected on a membrane filter in the breathing zone of an individual or by area sampling in a specific location. This practice is based on the core procedures provided in the International Organization for Standardization (ISO) Standard ISO 8672(1)3, the National Institute for Occupational and Health (NIOSH) Manual of Analytical Methods, NIOSH 7400 (2), and the Occupational Safety and Health Administration (OSHA) Method ID 160 (3). This practice indicates the important points where these methods differ, and provides information regarding the differences. However, selecting portions of procedures from different published methods generally requires a user to report that they have used a modification to a method rather than claim they have used the method as written. This practice further gives guidance on how differential counting techniques may be used to indicate where a population of fibers may be asbestos.1.2 The practice is used for routine determination of an index of occupational exposure to airborne fibers in mines, quarries, or other locations where ore may be processed or handled. The method gives an index of airborne fiber concentration. The method provides an estimate of the fraction of counted fibers that may be asbestos. This practice should be used in conjunction with electron microscopy (See Appendix X1) for assistance in identification of fibers.1.3 This practice specifies the equipment and procedures for sampling the atmosphere in the breathing zone of an individual and for determining the number of fibers accumulated on a filter membrane during the course of an appropriately-selected sampling period. The method may also be used to sample the atmosphere in a specific location in a mine or in a room of a building (area sampling).1.4 The ideal working range of this practice extends from 100 fibers/mm2 to 1300 fibers/mm2 of filter area. For a 1000-L air sample, this corresponds to a concentration range from approximately 0.04 to 0.5 fiber/mL (or fiber/cm3). Lower and higher ranges of fiber concentration can be measured by reducing or increasing the volume of air collected. However, when this practice is applied to personal sampling in mines and quarries, the level of total suspended particulate may impose an upper limit to the volume of air that can be sampled if the filters produced are to be of appropriate particulate loading for fiber counting.1.5 Users should determine their own limit of detection using the procedure in Practice D6620. For reference, the NIOSH 7400 method gives the limit of detection as 7 fibers/mm2 of filter area. For a 1000-L air sample, this corresponds to a limit of detection of 0.0027 fiber/mL (or fiber/cm3). For OSHA ID 160 the limit of detection is given as 5.5 fibers/mm2 of filter area. For a 1000-L air sample, this corresponds to a limit of detection of 0.0022 fiber/mL (or fiber/cm3).1.6 If this practice yields a fiber concentration that does not exceed one-half the permissible exposure limit or threshold limit value for the particular regulated fiber variety, no further action may be necessary. If the fiber concentration exceeds one-half of the regulated permissible exposure limit or threshold limit value for the particular regulated fiber variety, it is necessary to examine the data to determine if more than 50 % of the counted fibers are thinner than 1.0 μm, or thicker but with an appearance of asbestos (curvature, splayed ends, or the appearance of a bundle).1.7 The mounting medium used in this practice has a refractive index of approximately 1.45. Fibers with refractive indices in the range of 1.4 to 1.5 will exhibit reduced contrast, and may be difficult to detect.1.8 Fibers less than approximately 0.2 µm in diameter may not be detected by this practice. (4)1.9 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety problems 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. For specific precautionary statements, see Section 7.

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