5.1 This test method is applicable to the measurement of airborne asbestos in a wide range of ambient air situations and for detailed evaluation of any atmosphere for asbestos structures. Most fibers in ambient atmospheres are not asbestos, and therefore, there is a requirement for fibers to be identified. Most of the airborne asbestos fibers in ambient atmospheres have diameters below the resolution limit of the light microscope. This test method is based on transmission electron microscopy, which has adequate resolution to allow detection of small thin fibers and is currently the only technique capable of unequivocal identification of the majority of individual fibers of asbestos. Asbestos is often found, not as single fibers, but as very complex, aggregated structures, which may or may not also be aggregated with other particles. The fibers found suspended in an ambient atmosphere can often be identified unequivocally if sufficient measurement effort is expended. However, if each fiber were to be identified in this way, the analysis would become prohibitively expensive. Because of instrumental deficiencies or because of the nature of the particulate matter, some fibers cannot be positively identified as asbestos even though the measurements all indicate that they could be asbestos. Therefore, subjective factors contribute to this measurement, and consequently, a very precise definition of the procedure for identification and enumeration of asbestos fibers is required. The method defined in this test method is designed to provide a description of the nature, numerical concentration, and sizes of asbestos-containing particles found in an air sample. The test method is necessarily complex because the structures observed are frequently very complex. The method of data recording specified in the test method is designed to allow reevaluation of the structure-counting data as new applications for measurements are developed. All of the feasible specimen preparation techniques result in some modification of the airborne particulate matter. Even the collection of particles from a three-dimensional airborne dispersion on to a two-dimensional filter surface can be considered a modification of the particulate matter, and some of the particles, in most samples, are modified by the specimen preparation procedures. However, the procedures specified in this test method are designed to minimize the disturbance of the collected particulate material.5.2 This test method applies to analysis of a single filter and describes the precision attributable to measurements for a single filter (see 13.1). Multiple air samples are usually necessary to characterize airborne asbestos concentrations across time and space. The number of samples necessary for this purpose is proportional to the variation in measurement across samples, which may be greater than the variation in a measurement for a single sample.1.1 This test method2 is an analytical procedure using transmission electron microscopy (TEM) for the determination of the concentration of asbestos structures in ambient atmospheres and includes measurement of the dimension of structures and of the asbestos fibers found in the structures from which aspect ratios are calculated.1.1.1 This test method allows determination of the type(s) of asbestos fibers present.1.1.2 This test method cannot always discriminate between individual fibers of the asbestos and non-asbestos analogues of the same amphibole mineral.1.2 This test method is suitable for determination of asbestos in both ambient (outdoor) and building atmospheres.1.2.1 This test method is defined for polycarbonate capillary-pore filters or cellulose ester (either mixed esters of cellulose or cellulose nitrate) filters through which a known volume of air has been drawn and for blank filters.1.3 The upper range of concentrations that can be determined by this test method is 7000 s/mm2. The air concentration represented by this value is a function of the volume of air sampled.1.3.1 There is no lower limit to the dimensions of asbestos fibers that can be detected. In practice, microscopists vary in their ability to detect very small asbestos fibers. Therefore, a minimum length of 0.5 μm has been defined as the shortest fiber to be incorporated in the reported results.1.4 The direct analytical method cannot be used if the general particulate matter loading of the sample collection filter as analyzed exceeds approximately 10 % coverage of the collection filter by particulate matter.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 is applicable to the measurement of airborne carbon nanotubes in a wide range of ambient air situations and for evaluation of any atmosphere for carbon nanotube structures. Single carbon nanotube structures in ambient atmospheres have diameters below the resolution limit of the light microscope. This test method is based on transmission electron microscopy, which has adequate resolution to allow detection of small thin single carbon nanotubes and is currently a reliable technique capable of unequivocal identification of the majority of nanotube structures. Carbon nanotubes are often found, not as single carbon nanotubes, but as very complex, aggregated structures, which may or may not be aggregated with other particles.5.2 This test method applies to the analysis of a single filter and describes the precision attributable to measurements for a single filter. Multiple air samples are usually necessary to characterize airborne nanotube structure concentrations across time and space. The number of samples necessary for this purpose is proportional to the variation in measurement across samples, which may be greater than the variation in measurement for a single sample.1.1 This test method is an analytical procedure using transmission electron microscopy (TEM) for the determination of the concentration of carbon nanotubes and carbon nanotube-containing particles in ambient atmospheres.1.1.1 This test method is suitable for determination of carbon nanotubes in both ambient (outdoor) and building atmospheres.1.2 This test method is defined for polycarbonate capillary pore filters through which a known volume of air has been drawn and for blank filters.1.3 The direct analytical method cannot be used if the general particulate matter loading of the sample collection filter as analyzed exceeds approximately 25 % coverage of the collection filter by particulate matter.1.4 Units—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 Moisture measurement in natural gas is performed to ensure sufficiently low levels for gas purchase contracts and to prevent corrosion. Moisture may also contribute to the formation of hydrates.5.2 The significance of applying TDLAS for the measurement of moisture in natural gas is TDLAS analyzers may have a very high degree of selectivity and minimal interference in many natural gas streams. Additionally, the sensing components of the analyzer are not wetted by the natural gas, limiting the potential damage from corrosives such as hydrogen sulfide (H2S) and liquid contaminants such as ethylene glycol or compressor oils. As a result, the TDLAS analyzer is able to detect changes in concentration with relatively rapid response. It should be noted that the mirrors of a TDLAS analyzer may be fouled if large quantities of condensed liquids enter the sample cell. In most cases the mirror can be cleaned without the need for recalibration or realignment.5.3 Primary applications covered in this method are listed in 5.3.1 – 5.3.3. Each application may have differing requirements and methods for gas sampling. Additionally, different natural gas applications may have unique spectroscopic considerations.5.3.1 Raw natural gas is found in production, gathering sites, and inlets to gas-processing plants characterized by potentially high levels of water (H2O), carbon dioxide (CO2), hydrogen sulfide (H2S), and heavy hydrocarbons. Gas-conditioning plants and skids are normally used to remove H2O, CO2, H2S, and other contaminants. Typical moisture concentration after dehydration is roughly 20 to 200 ppmv. Protection from liquid carryover such as heavy hydrocarbons and glycols in the sample lines is necessary to prevent liquid pooling in the cell or the sample components.5.3.2 Underground gas storage facilities are high-pressure caverns used to store large volumes of gas for use during peak demand. Underground storage caverns can reach pressures as high as 275 bar. Multistage and heated regulator systems are usually required to overcome significant temperature drops resulting from gas expansion in the sample.5.3.3 High-quality “sales gas” is found in transportation pipelines, natural gas distribution (utilities), and natural gas power plant inlets. The gas is characterized by a very high percentage of methane (90 to 100 %) with small quantities of other hydrocarbons and trace levels of contaminates.1.1 This test method covers online determination of vapor phase moisture concentration in natural gas using a tunable diode laser absorption spectroscopy (TDLAS) analyzer also known as a “TDL analyzer.” The particular wavelength for moisture measurement varies by manufacturer; typically between 1000 and 10 000 nm with an individual laser having a tunable range of less than 10 nm.1.2 Process stream pressures can range from 700-mbar to 700-bar gage. TDLAS is performed at pressures near atmospheric (700- to 2000-mbar gage); therefore, pressure reduction is typically required. TDLAS can be performed in vacuum conditions with good results; however, the sample conditioning requirements are different because of higher complexity and a tendency for moisture ingress and are not covered by this test method. Generally speaking, the vent line of a TDL analyzer is tolerant to small pressure changes on the order of 50 to 200 mbar, but it is important to observe the manufacturer’s published inlet pressure and vent pressure constraints. Large spikes or steps in backpressure may affect the analyzer readings.1.3 The typical sample temperature range is -20 to 65 °C in the analyzer cell. While sample system design is not covered by this standard, it is common practice to heat the sample transport line to around 50 °C to avoid concentration changes associated with adsorption and desorption of moisture along the walls of the sample transport line.1.4 The moisture concentration range is 1 to 10 000 parts per million by volume (ppmv). It is unlikely that one spectrometer cell will be used to measure this entire range. For example, a TDL spectrometer may have a maximum measurement of 1 ppmv, 100 ppmv, 1000 ppmv, or 10 000 ppmv with varying degrees of accuracy and different lower detection limits.1.5 TDL absorption spectroscopy measures molar ratios such as ppmv or mole percentage. Volumetric ratios (ppmv and %) are not pressure dependent. Weight-per-volume units such as milligrams of water per standard cubic metre or pounds of water per standard cubic foot can be derived from ppmv at a specific condition such as standard temperature and pressure (STP). Standard conditions may be defined differently for different regions and entities. The dew point can be estimated from ppmv and pressure. Refer to Test Method D1142 and ISO 18453.1.6 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Some specific hazards statements are given in Section 8 on Hazards.1.8 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 useful for preparing extracts from fire debris for subsequent qualitative analysis by gas chromatography-mass spectrometry, see Test Method E1618.5.2 This practice is capable of removing a portion of the headspace vapors, containing quantities smaller than 0.1 µL/L of ignitable liquid residues, from a sample container and concentrating the ignitable liquid residues onto an adsorbent medium (1).5.2.1 Recovery from fire debris samples will vary, depending on factors including debris temperature, adsorbent temperature, container size, adsorptive material, headspace volume, sampling volume or sampling time and flow rate, and adsorptive competition from the sample matrix (2).5.3 The principal concepts of static headspace concentration are similar to those of static headspace (Practice E1388) and dynamic headspace concentration (Practice E1413). The static headspace concentration technique can be more sensitive than the static headspace technique and less sensitive than the dynamic. The static techniques do however leave the sample in a condition suitable for resampling, as only a portion, typically less than 10 %, of the headspace is withdrawn from a sample container (3).5.3.1 Re-sampling and analysis is possible with static headspace concentration onto an adsorbent tube, because only a portion of the headspace from the container is removed (3). Taking multiple headspace samples will continuously reduce the concentration of ignitable liquid vapors present, which can result in a change in relative composition of components and eventually non-recovery when the questioned headspace originally contained very low quantities of ignitable liquid residues (less than 0.1 µL/L).5.4 Common solid adsorbent/desorption procedure combinations in use are activated carbon/solvent elution and Tenax4 TA/thermal desorption.5.5 Solid adsorbent/desorption procedures not specifically described in this standard can be used as long as the practice has been validated as outlined in Section 11.1.1 This practice describes the procedure for separation of ignitable liquid residues from fire debris samples using static headspace concentration onto an adsorbent tube, for subsequent solvent elution or thermal desorption.1.2 Static headspace concentration onto an adsorbent tube involves removal of a headspace extract from a sample container (typically a jar, can, or bag), through a small hole punctured in the container, using a syringe or pump.1.3 Static headspace concentration systems for adsorption onto an adsorbent tube are illustrated and described.1.4 This practice is suitable for preparing extracts from fire debris samples containing a range of volumes (µL to mL) of ignitable liquid residues, with sufficient recovery for subsequent qualitative analysis (1).21.5 Alternative headspace concentration methods are listed in Section 2 (see Practices E1388, E1412, E1413, and E2154).1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.7 This standard cannot replace knowledge, skills, or abilities acquired through education, training, and experience (Practice E2917) and is to be used in conjunction with professional judgment by individuals with such discipline-specific knowledge, skills, and abilities.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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1.1 This test method covers procedures for the use of oxygen analyzers to measure the percentage of oxygen in an insulating glass unit where normal atmospheric air has been replaced with other gases such as argon, krypton, xenon, or sulfur hexafluoride (SF6). The procedure shows how to convert the measured percentage of oxygen in an insulating glass unit to the percentage of air in the unit, and subtracts the air percentage from 100 % to calculate the percentage of fill gas in the unit.1.2 This test method does not determine the type of fill gas. It only measures the percentage of oxygen in the gas in the space between the lites of an insulating glass unit.1.3 This test method is not applicable to insulating glass units containing open capillary/breather tubes.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 This test method provides a procedure for performing laboratory tests to evaluate relative deflagration parameters of dusts.5.2 The MEC as measured by this test method provides a relative measure of the concentration of a dust cloud necessary for an explosion.5.3 Since the MEC as measured by this test method may vary with the uniformity of the dust dispersion, energy of the ignitor, and propagation criteria, the MEC should be considered a relative rather than absolute measurement.5.4 If too weak an ignition source is used, the measured MEC would be higher than the “true” value. 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 MEC is independent of ignition energy. 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.5.5 The recommended ignition source for measuring the MEC of dusts in 20-L chambers is a 2500 or 5000 J pyrotechnic ignitor.4 Measuring the MEC at both ignition energies will provide information on the possible overdriving of the system.5 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.5.6 If a dust ignites with a 5000 J ignitor but not with a 2500 J ignitor in a 20-L chamber, this may be an overdriven system.5 In this case, it is recommended that the dust be tested with a 10 000 J ignitor in a larger chamber, such as a 1 m3-chamber, to determine if it is actually explosible.5.7 The values obtained by this test method are specific to the sample tested (particularly the particle size distribution) and the method used and are not to be considered intrinsic material constants.1.1 This test method covers the determination of the minimum concentration of a dust-air mixture that will propagate a deflagration in a near-spherical closed vessel of 20 L or greater volume.NOTE 1: The minimum explosible concentration (MEC) is also referred to as the lower explosibility limit (LEL) or lean flammability limit (LFL).1.2 Data obtained from this test 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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5.1 This test method is intended to provide a means for determining the concentration of argon in sealed insulating glass units under controlled conditions in compliance with the apparatus manufacturer's instructions.5.2 This is a non-destructive test method in that the edge seal of the test specimen is not breached in order to determine the argon gas concentration. However, damage to some glass coatings on the inner surfaces of the glass can occur.5.3 This test method has been developed based on data collected in a controlled laboratory environment.5.4 The device shall be used to determine the argon gas concentration in insulating glass units in a controlled laboratory environment. Refer to 12.3.5.5 This test method may be used to determine the argon gas concentration before, during, or after the insulating glass unit is subjected to durability tests.5.6 The accuracy of the test method is dependent upon the accuracy of the Spark Emission Spectroscope. When the concentration of the argon being measured is below certain levels, this test method is not applicable. See the spectroscope manufacturer’s literature for recommended levels of accuracy of a given model.1.1 This test method covers procedures for using a spark emission spectroscope to determine the concentration of argon gas in the space between the lites of a sealed insulating glass unit.1.2 This is a non-destructive test method.1.3 This test method shall be used only in a controlled laboratory environment.1.4 This test method is applicable for insulating glass units where argon has been added to the sealed insulating glass cavity and the balance of the gas is atmospheric air.1.5 This test method is applicable for clear, double-glazed insulating glass units.1.6 This test method is applicable for double-glazed insulating glass units with one lite having a metallic coating or tinted glass, or both, and with clear glass as the other lite.1.7 This test method is applicable for triple-glazed insulating glass units only when the center lite of glass has a metallic coating (either low emissivity (low E) or reflective) and both of the other lites are clear glass.1.8 This test method also includes a procedure for verifying the accuracy of the readings of the test apparatus.1.9 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.1.10 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific warning statements, refer to Section 7 on Hazards.1.11 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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Ranked set sampling is cost-effective, unbiased, more precise and more representative of the population than simple random sampling under a variety of conditions (1).3Ranked set sampling (RSS) can be used when:4.2.1 The population is likely to have stratification in concentrations of contaminant.4.2.2 There is an auxiliary variable.4.2.3 The auxiliary variable has strong correlation with the primary variable.4.2.4 The auxiliary variable is either quick or inexpensive to measure, relative to the primary variable.This guide provides a ranked set sampling method only under the rule of equal allocation. This guide is intended for those who manage, design, and implement sampling and analysis plans for management of wastes and contaminated media. This guide can be used in conjunction with the DQO process (see Practice D 5792).1.1 This guide describes ranked set sampling, discusses its relative advantages over simple random sampling, and provides examples of potential applications in environmental sampling.1.2 Ranked set sampling is useful and cost-effective when there is an auxiliary variable, which can be inexpensively measured relative to the primary variable, and when the auxiliary variable has correlation with the primary variable. The resultant estimation of the mean concentration is unbiased, more precise than simple random sampling, and more representative of the population under a wide variety of conditions.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 The test method provides a relatively simple method for determination of the concentration of RDP without the need for specialty equipment built expressly for such purposes.5.2 Using this test method will afford investigators of radon in dwellings a technique by which the RDP can be determined. The use of the results of this test method are generally for diagnostic purposes and are not necessarily indicative of results that might be obtained by longer term measurement methods.5.3 An improved understanding of the frequency of elevated radon in buildings and the health effect of exposure has increased the importance of knowledge of actual exposures. The measurement of RDP, which are the direct cause of potential adverse health effects, should be conducted in a manner that is uniform and reproducible; it is to this end that this test method is addressed.1.1 This test method provides instruction for using the grab sampling filter technique to determine accurate and reproducible measurements of indoor radon decay product (RDP) concentrations and of the working level (WL) value corresponding to those concentrations.1.2 Measurements made in accordance with this test method will produce RDP concentrations representative of closed-building conditions. Results of measurements made under closed-building conditions will have a smaller variability and are more reproducible than measurements obtained when building conditions are not controlled. This test method may be utilized under non-controlled conditions, but a greater degree of variability in the results will occur. Variability in the results may also be an indication of temporal variability present at the sampling site.1.3 This test method utilizes a short sampling period and the results are indicative of the conditions only at the place and time of sampling. The results obtained by this test method are not necessarily indicative of longer terms of sampling and should not be confused with such results. The averaging of multiple measurements over hours and days can, however, provide useful screening information. Individual measurements are generally obtained for diagnostic purposes.1.4 The range of the test method may be considered from 0.0005 WL to unlimited working levels, and from 40 Bq/m3 to unlimited for each individual radon decay product.1.5 This test method provides information on equipment, procedures, and quality control. It provides for measurements within typical residential or building environments and may not necessarily apply to specialized circumstances, for example, clean rooms.1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. See Section 9 for additional precautions1.8 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 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 or operate a reactor while avoiding the creation of flammable gas compositions therein, or to store or ship materials safely. NFPA 69 provides guidance for the practical use of LOC data, including the appropriate safety margin to use.5.2 Examples of LOC data applications can be found in references (3-5).NOTE 2: The LOC values reported in references (6-8), and relied upon by a number of modern safety standards (such as NFPA 69 and NFPA 86) were obtained mostly in a 5-cm diameter flammability tube. This diameter may be too small to mitigate the flame quenching influence impeding accurate determination of the LOC of most fuels. The 4-L minimum volume specified in Section 7 would correspond to a diameter of at least 20 cm. As a result, some LOC values determined using these test methods are approximately 1.5 vol % lower than the previous values measured in the flammability tube, and are more appropriate for use in fire and explosion hazard assessment studies.5.3 Much of the previous literature LOC data (6-8) were measured in the flammability tube.5.4 Accepted LOC values (when nitrogen is the inert gas) determined for the five reference gases using these test methods in 20-L and 120-L test enclosures have been reported in Zlochower (9), and are summarized below:Hydrogen—4.6 % in 120-L, 4.7 % in 20-LCarbon Monoxide—5.1 % in 120-LMethane—11.1 % in 120-L, 10.7 % in 20-LEthylene—8.5 % in 120-L, 8.6 % in 20-LPropane—10.7 % in 120-L, 10.5 % in 20-LNOTE 3: For carbon monoxide, results are sensitive to the humidity of the test mixture in the enclosure. Presence of a small concentration of water vapor facilitates combustion and promotes flame propagation by supplying the hydrogen (H) and hydroxyl (OH) free radicals for the chain branching reactions. For conservative results, provisions are made to humidify the test air to near saturation.5.5 These test methods are often used to determine the LFL (lower flammability limit) and UFL (upper flammability limit) of gases and vapors initially at or near atmospheric pressure. Accepted LFL and UFL values determined for the five reference gases using these test methods have been reported in Zlochower (9).5.6 These test methods are also used to determine the maximum content of flammable gas which, when mixed with specified inert gas, is not flammable in air (ISO 10156, CGA P-23).5.7 A minimum purity of 99 % is recommended for the standard reference gases used for the commissioning (qualification) of the test apparatus and for the periodic verification of data quality.1.1 These test methods cover the determination of the limiting oxygen (oxidant) concentration of mixtures of oxygen (oxidant) and inert gases with flammable gases and vapors at a specified initial pressure and initial temperature.1.2 These test methods may also be used to determine the limiting concentration of oxidizers other than oxygen.1.3 Differentiation among the different combustion regimes (such as the hot flames, cool flames, and exothermic reactions) is beyond the scope of these test methods.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 These test methods 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 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.1.6 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 The measurement of particulate matter and collected residue emission rates is an important test method widely used in the practice of air pollution control. Particulate matter measurements after control devices are necessary to determine total emission rates into the atmosphere.5.1.1 These measurements, when approved by national, state, provincial, or other regional agencies, are often required for the purpose of determining compliance with regulations and statutes.5.1.2 The measurements made before and after control devices are often necessary to demonstrate conformance with regulatory or contractual performance specifications.5.2 The collected residue obtained with this test method is also important in characterizing stack emissions. However, the utility of these data is limited unless a chemical analysis of the collected residue is performed.5.3 These measurements also can be used to calibrate continuous particulate emission monitoring systems by correlating the output of the monitoring instruments with the data obtained by using this test method.1.1 This test method2 covers a method for the measurement of particulate matter (dust) concentration in emission gases in the concentrations below 20 mg/m3 standard conditions, with special emphasis around 5 mg/m3.1.2 To meet the requirements of this test method, the particulate sample is weighed to a specified level of accuracy. At low dust concentrations, this is achieved by:1.2.1 Precise and repeatable weighing procedures,1.2.2 Using low tare weight weighing dishes,1.2.3 Extending the sampling time at conventional sampling rates, or1.2.4 Sampling at higher rates at conventional sampling times (high-volume sampling).1.3 This test method differs from Test Method D3685/D3685M by requiring the mass measurement of filter blanks, specifying weighing procedures, and requiring monitoring of the flue gas flow variability over the testing period. It requires that the particulate matter collected on the sample filter have a mass at least five times a positive mass difference on the filter blank. High volume sampling techniques or an extension of the sampling time may be employed to satisfy this requirement. This test method has tightened requirements on sampling temperature fluctuations and isokinetic sampling deviation. This test method has eliminated the in-stack filtration technique.1.4 This test method may be used for calibration of automated monitoring systems (AMS). If the emission gas contains unstable, reactive, or semi-volatile substances, the measurement will depend on the filtration temperature.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 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 morphology, elemental composition, and crystal structure. The analysis technique has the ability to positively identify SCCW.Note 1—This test method assumes that the analyst is familiar with the operation of TEM/EDS instrumentation and the interpretation of data obtained using these techniques.This test method is applicable for the measurement of the total population of SCCW fibers including fibers with diameters ≤0.1 μm.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 (2,5,6).1.1 This test method covers the sampling methods and analysis techniques used to assess the airborne concentration and size distribution 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 filtration of a known quantity of air through a filter. The filter is subsequently evaluated with a transmission electron microscope (TEM) for the number of fibers meeting appropriately selected morphological and compositional criteria. This test method has the ability to distinguish among different types of fibers based on energy dispersive X-ray spectroscopy (EDS) analysis and selected area electron diffraction (SAED) analysis. 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 0.5 μm in length, less than 3 μm in width, and have an aspect ratio equal to or greater than 5:1 (1). The data are directly convertible to a statement of concentration per unit volume of air sampled. This test method is limited by the amount of coincident interference particles.1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.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 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 Low operating temperature fuel cells such as proton exchange membrane fuel cells (PEMFCs) require high purity hydrogen for maximum material performance and lifetime. Measurement of particulates in hydrogen is necessary for assuring a feed gas of sufficient purity to satisfy fuel cell and internal combustion system needs as defined in SAE J2719. The particulates in hydrogen fuel for fuel cell vehicles (FCV) and gaseous hydrogen powered internal combustion engine vehicles may adversely affect pneumatic control components, such as valves, or other critical system components. Therefore, the concentration of particulates in the hydrogen fuel should be limited as specified by ISO 14687-2, SAE J2719, or other hydrogen fuel quality specifications.5.2 Although not intended for application to gases other than hydrogen fuel, techniques within this test method can be applied to gas samples requiring determination of particulate concentration.1.1 This test method is primarily intended for gravimetric determination of particulate concentration in hydrogen intended as a fuel for fuel cell or internal combustion engine powered vehicles. This test method describes operating and quality control procedures required to obtain data of known quality satisfying the requirements of SAE J2719. This test method can be applied to other gaseous samples requiring determination of particulates provided the user’s data quality objectives are satisfied.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this 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 and health 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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