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1.1 This test method covers the determination of the ignition of a dust dispersed in air, within a closed vessel.1.2 This test method provides a measure of dust explosion pressure and rate of pressure rise. It does not provide a definitive determination of the flammability of a dust and has other severe limitations which are identified in Section 5. The preferred method for the design of safety equipment is Test Method E1226.1.3 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 and health practices and determine the applicability of regulatory limitations prior to use. For specific safety precautions see Section 7.1.4 The values stated in inch-pound units are to be regarded as the standard. The values in parentheses are for information only.

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5.1 This test method provides a procedure for performing laboratory tests to determine the minimum autoignition temperature (MAIT) of a dust cloud.5.2 The test data developed from this test method can be used to limit the temperature to which a dust cloud is exposed so as to prevent ignition of the cloud. Because of the short duration of the test, the data obtained are most applicable to industrial equipment where dust is present as a cloud for a short time. Because of the small scale of the test and the possible variation of the MAIT value with scale, the data obtained by this test method may not be directly applicable to all industrial conditions.5.3 The MAIT data can also be used in conjunction with minimum spark ignition data to evaluate the hazards of grinding and impact sparks in the presence of dust clouds (1 and 2).35.4 The test values obtained are specific to the sample tested, the method used, and the test equipment utilized. The test values are not to be considered intrinsic material constants, but may be used as a relative measure of the temperature at which a dust cloud self ignites.5.5 The test data are for cloud ignition. Dust in the form of a layer may ignite at significantly lower temperatures than the same dust in the form of a cloud (3). For liquid chemicals, see Test Method E659.1.1 This test method covers the minimum temperature at which a given dust cloud will autoignite when exposed to air heated in a furnace at local atmospheric pressure.1.2 Data obtained from this test method provide a relative measure of dust cloud autoignition temperatures.1.3 This test method should be used to measure and describe the properties of materials, products, or assemblies in response to heat and flame under controlled laboratory conditions and should not be used to describe or appraise the fire hazard or fire risk of materials, products, or assemblies under actual fire conditions. However, results of this test method may be used as elements of a fire risk assessment which takes into account all of the factors which are pertinent to an assessment of the fire hazard of a particular end use.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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5.1 This test method provides a procedure for performing laboratory tests to evaluate relative deflagration parameters of dusts.5.2 Knowledge of the limiting oxygen (oxidant) concentration is needed for safe operation of some chemical processes. This information may be needed in order to start up, shut down or operate a process while avoiding the creation of flammable dust-gas atmospheres therein, or to pneumatically transport materials safely. NFPA 69 provides guidance for the practical use of LOC data, including the appropriate safety margin to use.5.3 Since the LOC as measured by this method may vary with the energy of the ignitor and the propagation criteria, the LOC should be considered a relative rather than absolute measurement.5.4 If too weak an ignition source is used, the measured LOC would be higher than the “true” value and would not be sufficiently conservative. This is an ignitability limit rather than a flammability limit, and the test could be described as “underdriven.” Ideally, the ignition energy is increased until the measured LOC is independent of ignition energy (that is, the “true” value). However, at some point the ignition energy may become too strong for the size of the test chamber, and the system becomes “overdriven.” When the ignitor flame becomes too large relative to the chamber volume, a test could appear to result in an explosion, while it is actually just dust burning in the ignitor flame with no real propagation beyond the ignitor (1-3).5 This LOC value would be overly conservative.5.5 The recommended ignition source for measuring the LOC of dusts in 20-L chambers is a 2500-J pyrotechnic ignitor.6 This ignitor contains 0.6 g of a powder mixture of 40 % zirconium, 30 % barium nitrate, and 30 % barium peroxide. Measuring the LOC at several ignition energies will provide information on the possible overdriving of the system to evaluate the effect of possible overdriving in a 20-L chamber, comparison tests may also be made in a larger chamber such as a 1-m3 chamber (1-3).5.6 The values obtained by this testing technique are specific to the sample tested (particularly the particle size distribution) and the method used and are not to be considered intrinsic material constants.NOTE 1: Much of the previously published LOC data (4). were obtained using a spark ignition source in a 1.2-L Hartmann chamber and may not be sufficiently conservative. The European method of LOC determination EN 14034–4 uses two 1000-J pyrotechnic igniters in the 20-L chamber.1.1 This test method is designed to determine the limiting oxygen concentration of a combustible dust dispersed in a mixture of air with an inert/nonflammable gas in a near-spherical closed vessel of 20 L or greater volume.1.2 Data obtained from this method provide a relative measure of the deflagration characteristics of dust clouds.1.3 This test method should be used to measure and describe the properties of materials in response to heat and flame under controlled laboratory conditions and should not be used to describe or appraise the fire hazard or fire risk of materials, products, or assemblies under actual fire conditions. However, results of this test may be used as elements of a fire risk assessment that takes into account all of the factors that are pertinent to an assessment of the fire hazard of a particular end use.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. Specific precautionary statements are given in Section 8.1.6 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 test method is useful for determining the amount of metallic zinc in zinc dust pigment, and also in dried films of both inorganic and organic zinc-rich coatings. Test Methods D521 is an appropriate method for analyzing zinc dust, but has shortcomings when applied to samples of cured coatings.1.1 This test method covers the determination by differential scanning calorimetry of the metallic zinc content of both zinc-dust pigment, and of dried films of zinc-rich coatings. This test method is applicable to both inorganic and organic zinc-rich coatings.1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.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 guide describes factors to be considered by an investigator designing a sampling program to compare the asbestos dust loadings in two environments and presents statistical methods for making the comparison. Each user is responsible for the design of an investigation and the interpretation of data collected when using dust data.5.2 This guide does not deal with situations where dusts of different compositions or from different surfaces are to be evaluated.5.3 This guide describes methods for interpreting the results of sampling and analysis performed in accordance with Test Methods D5755 and D6480. It may be appropriate to use the procedures in this guide with other dust collection and analysis methods, but it is the responsibility of the user to make this determination.5.4 The methods described in this guide are not intended to be used alone. They are intended to be used along with various evaluation methods that may include consideration of building use, activities within the building, air sampling, asbestos surveys (refer to Practice E2356), evaluation of building history and study of building ventilation systems.5.5 This guide describes methods for comparing environments and does not draw any conclusions relating asbestos surface loadings to the potential safety or habitability of buildings.5.6 This guide does not address risk assessments or the use of dust sampling in risk assessment. Health based risk assessments are beyond the scope of this guide.5.7 Warning—Asbestos fibers are acknowledged carcinogens. Breathing asbestos fibers can result in disease of the lungs including asbestosis, lung cancer, and mesothelioma. Precautions should be taken to avoid creating and breathing airborne asbestos particles when sampling and analyzing materials suspected of containing asbestos. Regulatory requirements addressing asbestos are defined by USEPA3,4 and OSHA.51.1 There are multiple purposes for determining the loading of asbestos in dust on surfaces. Each particular purpose may require unique sampling strategies, analytical methods, and procedures for data interpretation. Procedures are provided to facilitate application of available methods for determining asbestos surface loadings and/or asbestos loadings in surface dust for comparison between two environments. At present, this guide addresses one application of the ASTM surface dust methods. It is anticipated that additional areas will be added in the future. It is not intended that the discussion of one application should limit use of the methods in other areas.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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific warning statements, see 5.7.1.3 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 requirements for wipe sampling materials that are used to collect settled dusts on surfaces for the subsequent determination of lead. The wipes shall be tested for conformance to background lead, lead recoverability, collection efficiency, ruggedness which shall be determined using butted vinyl-composite floor tiles as a test surface, moisture content, coefficient of variation in mass, linear dimensions such as mean area and mean length, and mean thickness requirements.1.1 This specification covers requirements for wipes that are used to collect settled dusts on surfaces for the subsequent determination of lead.1.2 For wipe materials used for the determination of beryllium in surface dust refer to Specification D7707. This is mentioned to insure that users of wipes recognize that there is some relationship between the analytical backgrounds found in wipes and the analyte of interest.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 Ultrasonic extraction using dilute nitric acid is a simpler and easier method for extracting lead from environmental samples than are traditional digestion methods that employ hot plate or microwave digestion with concentrated acids (3), (5), (7), (8). Hence, ultrasonic extraction may be used in lieu of the more rigorous strong acid/high temperature digestion methods (for example, see Ref (3) and Test Method E1613), provided that the performance is demonstrated using accepted criteria as delineated in Guide E1775.5.2 In contrast with hot plate or microwave digestion techniques, ultrasonic extraction is field-portable, which allows for on-site sample analysis.1.1 This practice covers an ultrasonic extraction procedure for the extraction of lead from environmental samples of interest in lead abatement and renovation (or related) work, for analytical purposes.1.2 Environmental matrices of concern include dry paint films, settled dusts, soils, and air particulates.1.3 Samples subjected to ultrasonic extraction are prepared for subsequent determination of lead by laboratory analytical methods.1.4 This practice includes, where applicable, descriptions of procedures for sample homogenization and weighing prior to ultrasonic extraction.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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5.1 This practice may be used to collect dust from carpeted or bare floor surfaces for gravimetric or chemical analysis. The collected sample is substantially unmodified by the sampling procedure.5.2 This practice provides for a reproducible dust removal rate from level loop and plush carpets, as well as bare floors. It has the ability to achieve relatively constant removal efficiency at different loadings of floor dust.5.3 This practice also provides for the efficient capture of semivolatile organic chemicals associated with the dust. The test system can be fitted with special canisters downstream of the cyclone for the capture of specific semivolatile organic chemicals that may volatilize from the dust particles during collection.5.4 This practice does not describe procedures for evaluation of the safety of floor surfaces or the potential human exposure to floor dust. It is the user's responsibility to evaluate the data collected by this practice and make such determinations in the light of other available information.5.5 This practice provides per-event dust chemical concentration and chemical loading. Advantages and trade-offs of different sampling approaches have been discussed (7).5.6 This practice uses a removable, cleanable dropout jar that facilitates per-event sampling. Other per-event vacuum attachments are commercially available. These are not directly comparable with composite sampling done using whole vacuum cleaner bags.1.1 This practice covers a procedure for the collection of a sample of dust from carpets and bare floors that can be analyzed for inorganic metals such as lead and organic compounds such as pesticides and other semi-volatile organic compounds (SVOCs).1.2 This practice is applicable to a variety of carpeted and bare floor surfaces. It has been tested for level loop and plush pile carpets and bare wood floors, specifically. This practice is not applicable to elevated, non-floor surfaces.1.3 This practice is not intended for the collection and evaluation of dust for the presence of asbestos fibers.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 practice describes use of a sampling device, the High-Volume Small Surface Sampler (HVS3). Other event-based sampling devices that use commercially available vacuum attachments are not in scope. Composite sampling using whole vacuum cleaner bags is not in scope. Other approaches for floor or non-floor surface sampling (Practices D6966, D6661, D7144) are not within the scope.1.6 This practice only applies to the HVS3. Other dust sampling methods may or may not be directly comparable. Method evaluation for other dust sampling approaches is encouraged. This could be done by comparison with methods outlined in this standard practice for HVS3 or through independent evaluation using field spikes and certified reference materials.1.7 This practice provides information on dust loading, chemical dust concentration, and chemical dust loading. Information on the type of floor, the floor surface area sampled, and amount of dust collected is required (see Fig. 2). Cleaning the vacuum attachments in between sampling events is also required (see Section 13).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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5.1 The test is designed to quantify the amount of dust control material added to calcined coke. The dust control material is applied to calcined coke to help maintain a dust-free environment. It generally serves no other useful purpose. It adds mass to the coke and can have a negative effect on the quality of carbon and graphite artifacts made from the treated coke. For these reasons the coke customer wants to know the amount of dust control material on the coke and can specify a maximum level.1.1 This test method covers the determination of the amount of material applied to calcined coke to control dust associated with coke handling and transportation.1.2 This test method is limited to those materials that are soluble in a solvent that can be used in a Soxhlet extraction type of apparatus such as methylene chloride (dichloro-methane).NOTE 1: Methylene chloride is the most popular solvent for removing dust control oil at the time this procedure is being written. Toluene and methyl chloroform, however, have been used with equal results on all cokes tested which have included only those sprayed with aromatic or waxy materials.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. For specific warning statements, see Section 7.1.5 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 practice is intended for the collection of settled dust samples for the subsequent measurement of beryllium and compounds. The practice is meant for use in the collection of settled dust samples that are of interest in clearance, hazard evaluation, risk assessment, and other purposes.5.2 This practice is intended solely for the collection of settled dust samples from hard, relatively smooth nonporous surfaces that may be compromised by water or other wetting agents and that are therefore not suitable for wet wipe sampling using Practice D6966 or micro-vacuum sampling using Practice D7144. Use of this practice for any purpose other than the intended purpose is discouraged due to the limited collection efficiency and high variability of dry wipe sampling as compared to wetted wipe or micro-vacuum sampling.35.3 This practice is less effective for collecting settled dust samples from surfaces with substantial texture such as rough concrete, brickwork, textured ceilings, and soft fibrous surfaces such as upholstery and carpeting. Micro-vacuum sampling using Practice D7144 may be more suitable for these surfaces.1.1 This practice covers the collection of settled dust containing beryllium and beryllium compounds on surfaces using the dry wipe sampling method, or both. These samples are collected in a manner that will permit subsequent extraction and determination of beryllium and compounds in the wipes using laboratory analysis techniques such as atomic spectrometry or fluorescence detection.1.2 This practice is limited in its scope to applications where wetted wipe sampling (using Practice D6966) or vacuum sampling (using Practice D7144) is not physically feasible (for example, if the surface to be wiped would be compromised by use of wetted wipes).1.3 This practice does not address the sampling design criteria (that is, sampling plan which includes the number and location of samples) that are used for clearance, hazard evaluation, risk assessment, and other purposes. To provide for valid conclusions, sufficient numbers of samples should be obtained as directed by a sampling plan. Additional guidance is provided in Guide D7659.1.4 This practice contains notes that are explanatory and are not part of the mandatory requirements of this practice.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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5.1 This test method provides a procedure for performing laboratory tests to determine the minimum ignition energy of a dust cloud.NOTE 1: For gases and vapors, see Test Method E582.5.2 The data developed by this test method may be used to assess the spark ignitibility of a dust cloud. Additional guidance on the significance of minimum ignition energy is in X1.1.5.3 The values obtained are specific to the sample tested, the method used and the test equipment used. The values are not to be considered intrinsic material constants.5.4 The MIE of a dust as determined using this procedure can be compared with the MIE's of reference dusts (using the same procedure) to obtain the relative sensitivity of the dust to spark ignition. An understanding of the relative sensitivity to spark ignition can be used to minimize the probability of explosions due to spark ignition.1.1 This test method determines the minimum ignition energy of a dust cloud in air by a high voltage spark.1.2 The minimum ignition energy (MIE) of a dust-cloud is primarily used to assess the likelihood of ignition during processing and handling. The likelihood of ignition is used to evaluate the need for precautions such as explosion prevention systems. The MIE is determined as the electrical energy stored in a capacitor which, when released as a high voltage spark, is just sufficient to ignite the dust cloud at its most easily ignitable concentration in air. The laboratory test method described in this standard does not optimize all test variables that affect MIE. Smaller MIE values might be determined by increasing the number of repetitions or optimizing the spark discharge circuit for each dust tested.1.3 In this test method, the test equipment is calibrated using a series of reference dusts whose MIE values lie within established limits. Once the test equipment is calibrated, the relative ignition sensitivity of other dusts can be found by comparing their MIE values with those of the reference dusts or with dusts whose ignition sensitivities are known from experience. X1.1 of this test method includes guidance on the significance of minimum ignition energy with respect to electrostatic discharges.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. Specific precautionary statements are given in Section 8.1.6 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 This test method is applicable to dusts and powders, and provides a procedure for performing laboratory tests to evaluate hot-surface ignition temperatures of dust layers.5.2 The test data can be of value in determining safe operating conditions in industrial plants, mines, manufacturing processes, and locations of material usage and storage.5.3 Due to variation of ignition temperature with layer thickness, the test data at one thickness may not be applicable to all industrial situations (see Appendix X1). Tests at various layer thicknesses may provide a means for extrapolation to thicker layers, as listed in the following for pulverized Pittsburgh bituminous coal dust (2). Mathematical modeling of layer ignition at various layer thicknesses is described in Ref. (3).Layer Thickness, mm Hot-Surface Ignition Temperature, °C6.4 3009.4 26012.7 24025.4 2105.4 This hot plate test method allows for loss of heat from the top surface of the dust layer, and therefore generally gives a higher ignition temperature for a material than Test Method E771, which is a more adiabatic system.5.5 This test method for dust layers generally will give a lower ignition temperature than Test Method E1491, which is for dust clouds. The layer ignition temperature is determined while monitoring for periods of minutes to hours, while the dust cloud is only exposed to the furnace for a period of seconds.NOTE 1: Much of the literature data for layer ignition is actually from a basket in a heated furnace (4), known as the modified Godbert-Greenwald furnace test. Other data are from nonstandardized hot plates (5-9).5.6 Additional information on the significance and use of this test method may be found in Ref. (10).1.1 This test method covers a laboratory procedure to determine the hot-surface ignition temperature of dust layers, that is, measuring the minimum temperature at which a dust layer will self-heat. The test consists of a dust layer heated on a hot plate.2,31.2 Data obtained from this test method provide a relative measure of the hot-surface ignition temperature of a dust layer.1.3 This test method should be used to measure and describe the properties of materials in response to heat and flame under controlled laboratory conditions and should not be used to describe or appraise the fire hazard or fire hazard risk of materials, products, or assemblies under actual fire conditions. However, results of this test method may be used as elements of a fire risk assessment that takes into account all of the factors that are pertinent to an assessment of the fire hazard risk of a particular end use product.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. Specific precautionary statements are given in Section 8.1.6 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.

定价： 590元 / 折扣价： 502 元 加购物车

5.1 This microvacuum sampling and indirect analysis method is used for the general testing of non-airborne dust samples for asbestos. It is used to assist in the evaluation of dust that may be found on surfaces in buildings such as ceiling tiles, shelving, electrical components, duct work, carpet, etc. This test method provides an index of the surface loading of asbestos structures in the dust per unit area analyzed as derived from a quantitative TEM analysis.5.1.1 This test method does not describe procedures or techniques required to evaluate the safety or habitability of buildings with asbestos-containing materials, or compliance with federal, state, or local regulations or statutes. It is the user’s responsibility to make these determinations.5.1.2 At present, no relationship has been established between asbestos-containing dust as measured by this test method and potential human exposure to airborne asbestos. Accordingly, the users should consider other available information in their interpretation of the data obtained from this test method.5.2 This definition of dust accepts all particles small enough to pass through a 1-mm (No. 18) screen. Thus, a single, large asbestos containing particle(s) (from the large end of the particle size distribution) dispersed during sample preparation may result in anomalously large asbestos surface loading results in the TEM analyses of that sample. It is, therefore, recommended that multiple independent samples are secured from the same area, and that a minimum of three samples be analyzed by the entire procedure.1.1 This test method covers a procedure to (a) identify asbestos in dust and (b) provide an estimate of the surface loading of asbestos in the sampled dust reported as the number of asbestos structures per unit area of sampled surface.1.1.1 If an estimate of the asbestos mass is to be determined, the user is referred to Test Method D5756.1.2 This test method describes the equipment and procedures necessary for sampling, by a microvacuum technique, non-airborne dust for levels of asbestos structures. The non-airborne sample is collected inside a standard filter membrane cassette from the sampling of a surface area for dust which may contain asbestos.1.2.1 This procedure uses a microvacuuming sampling technique. The collection efficiency of this technique is unknown and will vary among substrates. Properties influencing collection efficiency include surface texture, adhesiveness, electrostatic properties and other factors.1.3 Asbestos identified by transmission electron microscopy (TEM) is based on morphology, selected area electron diffraction (SAED), and energy dispersive X-ray analysis (EDXA). Some information about structure size is also determined.1.4 This test method is generally applicable for an estimate of the surface loading of asbestos structures starting from approximately 1000 asbestos structures per square centimetre.1.4.1 The procedure outlined in this test method employs an indirect sample preparation technique. It is intended to disperse aggregated asbestos into fundamental fibrils, fiber bundles, clusters, or matrices that can be more accurately quantified by transmission electron microscopy. However, as with all indirect sample preparation techniques, the asbestos observed for quantification may not represent the physical form of the asbestos as sampled. More specifically, the procedure described neither creates nor destroys asbestos, but it may alter the physical form of the mineral fibers.1.5 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.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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