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5.1 The SCCW may be present in the workplace atmosphere where these materials are manufactured, processed, transported, or used. The test methods discussed in this practice can be used to provide guidance when monitoring airborne concentrations of SCCW in these environments.5.2 Because of their visibility limitations, a significant fraction of the very small thin fibers that are present in some samples may not be detected by PCM or SEM. Therefore, TEM is considered to be the reference technique for the analysis of airborne SCCW. The TEM must be used to determine both fiber count and morphology when samples are from previously uncharacterized workplaces or materials.5.3 Although TEM is the reference technique, PCM or SEM are considered to be the primary screening methods for the analysis of airborne SCCW.5.4 Parallel TEM measurements shall be carried out, at least initially, to provide an index or relative measure of the fraction of total fibers that are seen by PCM or SEM. Only in instances when this percentage has been shown to be at a high and reproducible level may the lower resolution techniques (that is, PCM or SEM) be relied on exclusively.1.1 This practice is intended to assist individuals in the sampling and analysis of single-crystal ceramic whiskers (SCCW), such as silicon carbide and silicon nitride, in the workplace environment. It describes sampling and analytical techniques used to assess the airborne concentration and size distribution of SCCW, which may occur in and around the workplace where these materials are manufactured, processed, transported, or used.1.2 The protocols currently in use for asbestos and other fibrous materials have been used as a guide in developing sampling and analytical procedures for characterizing fibers produced from the manufacture and use of SCCW. The sampling and analysis protocols described here have been written specifically for SCCW, however, they may be appropriate for other man-made mineral fibers (MMMF).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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4.1 This test method provides a measurement of formaldehyde content (assay) of formaldehyde solutions. The results of these measurements can be used for specification acceptance.1.1 This test method covers the determination of the formaldehyde content of commercially available formaldehyde solutions ranging in concentration from 36 to 55 weight %.1.2 For purposes of determining conformance of an observed value or a calculated value using this test method to relevant specifications, test result(s) shall be rounded off “to the nearest unit” in the last right-hand digit used in expressing the specification limit, in accordance with the rounding-off method of Practice E29.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 For hazard information and guidance, see the supplier's Material Safety Data Sheet.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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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 SCCW fibers in these environments. It may be employed as part of a personal or area monitoring strategy.This test method is based on morphology and elemental composition. The analysis technique has the ability to identify SCCW.Note 1—This test method assumes that the analyst is familiar with the operation of SEM/EDS instrumentation and the interpretation of data obtained using these techniques.This test method is not appropriate for measurement of fibers with diameters ≤0.10 to 0.25 μm due to visibility limitations associated with SEM. The TEM method may be used to provide additional size information of SCCW if needed (see Practice D6058 for additional information on the use of this test method).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 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 collection of fibers by filtration of a known quantity of air through a filter. The filter is subsequently evaluated with a scanning electron microscope (SEM) for the number of fibers meeting appropriately selected morphological and compositional criteria. This test method has the ability to distinguish among many different types of fibers based on energy dispersive X-ray spectroscopy (EDS) 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 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 SEM (typically greater than 0.10 to 0.25 μm in width as determined in 12.1.5) and the amount of coincident interference particles.1.3 A more definitive analysis may be necessary to confirm the presence of fibers with diameters ≤0.10 to 0.25 μm in width. For this purpose, a transmission electron microscope (TEM) is appropriate. The use of the TEM method for the identification and size measurement of SCCW is described in Practice D6058 and Test Method 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 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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Steam distillation is a classical separation technique, useful for preparing extracts for analysis by gas chromatography GC/MS or GC/IR. Distillates are suitable for analysis according to Test Method E 1387 or Guide E 1618.The visible oily liquid extract can be used as a courtroom exhibit, unlike extracts produced by other separation procedures which are solutions rather than a neat liquid.This practice is not useful for the separation of water soluble ignitable liquids such as alcohols or ketones.Alternate separation and concentration methods are suggested if the concentration of flammable or combustible liquid residues is not detectable by odor.This is a destructive technique that should only be used when a representative portion of the sample can be reserved for reanalysis. Those portions of the sample subjected to this procedure may not be suitable for resampling. Consider using passive headspace concentration as described in Practice E 1412.1.1 This practice covers the procedure for separating visible quantities of water insoluble hydrocarbons from samples of fire debris.1.2 This practice is recommended only for samples which have a detectable odor of petroleum distillates when examined at room temperature.1.3 This practice can yield useful extracts by the application of a solvent to the distillation trap in the event that only small quantities of hydrocarbons are obtained.1.4 Alternate separation and concentration procedures are listed in the referenced documents.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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1.1 This test method covers a technique for field testing the concentration of aqueous urea-based diesel exhaust fluid (DEF) prescribed for use in diesel engines equipped with selective catalytic reduction technology and is not intended to circumvent or replace the more accurate determination of urea content by refractive index laboratory method, described in ISO 22241-2, Annex C.1.2 This test method is designed solely as a quantitative test to determine the concentration of urea in DEF and does not purport to determine the quality of DEF nor to detect trace or other contaminants therein. Biuret content of DEF creates a known bias in this test method. See section 9.2.1 for details.1.3 Units—The values stated in SI units are to be regarded as the 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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4.1 In this guide, the conditions, measurement apparatus, and procedures for measuring several characteristics of nanoparticle properties on three different instrument platforms using laser-amplified detection/power spectrum analysis (LAD/PSA) technology are described. This is a more recently developed technology, commercialized in 1990, than the older technology known as either photon correlation spectroscopy (PCS) or quasi-elastic light scattering (QLS)—those titles are interchangeable—developed first in 1961. Nanoparticle tracking analysis (NTA) is the most recent DLS technology to be commercialized. All three of these technologies fall under the broader category of DLS, based on the “dynamic” movement of the measured nanoparticles under Brownian motion.4.2 DLS in the lower end of the nanometre size range becomes progressively more difficult as the particle optical scattering coefficients drop sharply, reducing the scattered light intensity. The advantage of the heterodyne detection mode over the homodyne detection mode, especially at the low end of the nanometre range, will be explained.4.3 The LAD/PSA technology will be described and the major differences between it and the PCS-QLS and NTA technologies will be made clear. For thorough discussions of PCS-QLS, refer to Guide E2490, Test Method E3247, and ISO 22412 Annex Section A.1. For a thorough discussion of nanoparticle tracking analysis (NTA), refer to Guide E2834. For detailed information on laser-amplified detection/frequency power spectrum (LAD/FPS) technology, refer to ISO 22412 Annex Section A.2. General information on particle characterization practices can be found in Practice E1817, and nanotechnology terminology is given in Terminology E2456. Detailed information on sampling for particle characterization can be found in ISO 14488.1.1 The technology, laser-amplified detection/power spectrum analysis (LAD/PSA), is available in three different platforms, which will be designated as Platforms A, B, and C.1.1.1 Platform A—This is a solid-state probe configuration that serves as the optical bench in each of the platforms. It consists of an optical fiber coupler with a y-beam splitter that directs the scattered light signal from the nanoparticles at 180° back to a photodiode detector. The sensing end of the probe can be immersed in a suspension or positioned to measure one drop of a sample on top of the sensing surface.1.1.2 Platform B—The same probe is mounted in a case, positioned horizontally, to detect the signal from either a disposable or permanent cuvette.1.1.3 Platform C—Two probes are mounted in a case, horizontally, at opposite sides of a permanent sample cell. Both size distribution and zeta potential can be measured in this configuration.1.2 The laser beam travelling through the probe measuring the scattered light from the sample of nanoparticles, in all three platforms, is partially reflected back to the same photodiode detector, and the high optical power of the laser is added to the low optical power of the scattered light signal. The interference (mixing or beating) of those two signals is known as heterodyne beating. The resulting high-power detected signal provides the highest signal-to-noise ratio among dynamic light-scattering (DLS) technologies.1.3 This combined, amplified, optical signal is converted with a Fast Fourier transform (FFT) into a frequency power spectrum, then into a logarithmic power spectrum that is deconvolved into number and volume size distributions. The mean intensity, polydispersity, number and volume size distributions, concentration, and molecular weight can be reported in all platforms, plus zeta potential on Platform C.1.4 This technology is capable of measuring nanoparticles in a size range from 2.0 nanometres (nm) to 10 micrometres (µm), at concentrations in a suspending liquid medium up to 40 % cc/mL for all parameters given in 1.3.1.5 Units—The values stated in SI units are to be regarded as the 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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