5.1 The test can be used to evaluate the following:5.1.1 Classification or Comparison of Powders—There are several parameters that can be used to classify powders relative to each other, the most useful being the measured shear stresses, cohesion, flow function and angle of internal friction.5.1.2 Sensitivity Analysis—The shear cell can be used to evaluate the relative effects of a range of powder properties and/or environmental parameters such as (but not limited to) humidity, particle size and size distribution, particle shape and shape distribution, moisture content and temperature.5.1.3 Quality Control—The test can, in some circumstances, be used to assess the flow properties of a raw material, intermediate or product against pre-determined acceptance criteria.5.1.4 Storage Vessel Design—Mathematical models exist for the determination of storage vessel design parameters which are based on the flow properties of powders as generated by shear cell testing, requiring shear testing at a range of consolidating stresses as well as the measurement of the wall friction angle with respect to the material of construction of the storage vessel. The methods are detailed in Refs. (1-3).2NOTE 1: The quality of the result produced by this test method is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this test method are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors (4).Practice D3740 was developed for agencies engaged in the testing and/or inspection of soil and rock. As such it is not totally applicable to agencies performing this test method. However, users of this test method should recognize that the framework of Practice D3740 is appropriate for evaluating the quality of an agency performing this practice. Currently there is no known qualifying national authority that inspects agencies that perform this test method.1.1 This method covers the apparatus and procedures for measuring the incipient failure properties of a powder as a function of the normal stress for a given level of consolidation. The method also allows the further determination of the unconfined yield strength, internal friction angles, cohesion, flow function, major principal stress and wall friction angle (with the appropriate wall coupon fitted to the correct accessory).1.2 These parameters are most commonly used for the design of storage hoppers and bins using industry standard calculations and procedures. They can also provide relative classification or comparison of the flow behavior of different powders or different batches of the same powder if similar stress and shear regimes are encountered within the processing equipment.1.3 The apparatus is suitable for measuring the properties of powders with a maximum particle size of 1 mm. It is possible to test powders which have a small proportion of particles of 1 mm or greater, but they should be present in the bulk sample as no more than 5 % of the total mass in samples with a normal (Gaussian) size distribution.1.4 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.1.4.1 The procedures used to specify how data are collected/recorded or calculated, in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analysis methods for engineering design.1.5 Units—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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This guide is intended to provide general guidelines toward the design and utilization of SRT products used for healthcare documentation. It is intended to recommend the essential elements required of SRT systems in healthcare.This guide will not identify specific products or make recommendations regarding specific vendors or their products or services.A well-edited SRT document may result in improved quality over current methods of documentation, that is, handwritten notes and improved productivity over traditional dictation and transcription.Faster turnaround times.Legible documentation over handwriting has many advantages:Improved patient care communication.Enhanced patient safety.Reduced malpractice risks.Facilitation of appropriate reimbursement.For the medical transcriptionist and/or SRMTE, decreased repetitive stress injuries, such as neck, arm, wrist, and heel pain.Facilitation of cost controls related to document completion.Better utilization of medical language skills of MTs as productivity is not limited by keyboarding skills.1.1 This guide identifies system types and describes various features of speech recognition technology (SRT) products used to create the healthcare record. This will assist users (health information professionals, medical report originators, administrators, medical transcriptionists, speech recognition medical transcription editors (SRMTEs), system integrators, support personnel, trainers, and others) to make informed decisions relating to the design and utilization of SRT systems.1.2 This guide does not address the following items:1.2.1 System and data (voice and text) security.1.2.2 Administrative processes such as authentication of the document, productivity measurements, etc.

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3.1 This guide is the first known attempt to focus on security requirements and compare them to available and known technologies capable of meeting these requirements. This guide describes several steps to select the appropriate anti-CADDSS technology. These steps are described in Section 4.1.1 This general guide is intended to assist the user of the guide in selecting anti-CADDSS technologies to protect their product from CADDSS.1.2 This guide does not address or evaluate specific anti-CADDSS technologies, but rather suggests a path that assists in the objective evaluation of features of anti-CADDSS technologies available protection of their product from CADDSS.1.3 This guide provides a procedure to accomplish the proper selection of a security system. Specific technologies are not addressed, nor are any technologies recommended. There are many security systems available in the public marketplace today. Each has limitations and must be carefully measured against the parameters presented in this guide. Once this careful analysis is done, the user will be in a knowledgeable position to select a security system to meet his needs.

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4.1 This practice was developed to help manufacturers, designers, maintenance personnel, trainers, owners, employees, and customers of secure destruction services to provide a reasonable level of safety for everyone exposed to hazards of equipment used to provide those services.4.2 Sections 1 – 3 provide general information and definitions and apply to all plant-based and mobile secure destruction operations and equipment covered by this practice.4.3 Sections 5 – 8 provide requirements for design, manufacture, reconstruction, modification, operation, and maintenance of plant-based and mobile equipment used for secure destruction.1.1 This practice sets forth criteria for the design, manufacture, assembly, modification, operation, maintenance, service, or repair of plant-based and mobile secure destruction equipment.1.2 This practice is applicable both to plant-based (fixed facility) and mobile (truck-based) secure destruction operations engaged in collecting, receiving, storing, processing, transporting, or combinations thereof, media and related items to provide for secure destruction by physical or electronic alteration.1.3 In this practice, minimum safety requirements are established with respect to secure destruction operations and equipment.1.4 This practice applies to both new and existing mobile and plant-based secure destruction equipment.1.5 Units—The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered 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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General—This guide contains information regarding the use of membrane technology to recover and concentrate hazardous materials that have entered surface and ground water as the result of a spill. Membrane technology may be applied alone or in conjunction with other treatment techniques, as follows:Different types of membrane are used in series with filters to treat highly contaminated solutions reaching concentration levels of several parts per million of organic and inorganic materials.Different types of membranes are applied in series to treat very dilute concentrations (parts per billion level) of organic and inorganic compounds. Each membrane type has the ability to remove specific compounds, thus producing a concentrated fraction. This fraction may require final off-site treatment but provides a significant reduction in transportation costs due to the large volume reduction achieved.Membranes may be used in conjunction with destruction technologies such as advanced oxidation processes (AOPs). This method is recommended for dilute solutions. The membrane technology portion concentrates the compounds to an optimum level for AOP destruction.1.1 This guide covers considerations for the use of membrane technology in the mitigation of dilute concentrations of spilled chemicals into ground and surface waters.1.2 This guide addresses the application of membrane technology alone or in conjunction with other technologies.1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the 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 and health practices and determine the applicability of regulatory limitations prior to use. In addition, it is the responsibility of the user to ensure that such activity takes place under the control and direction of a qualified person with full knowledge of any potential or appropriate safety and health protocols.

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1.1 This terminology is a compilation of definitions of technical terms used in the underground infrastructure and plastic piping industry. Terms that are generally understood or adequately defined in other readily available sources are not included.1.2 When a term is used in an ASTM document for which Committee F36 is responsible, it is included only when judged, after review, by Subcommittee F36.91 to be a generally usable term.1.3 Definitions that are identical to those published by other ASTM committees or other standards organizations are identified with the committee number (for example, F17) or with the abbreviation of the name of the organization (for example, IUPAC, International Union of Pure and Applied Chemistry).1.4 A definition is a single sentence with additional information included in discussions.1.5 Definitions are followed by the committee responsible for the standard(s) (for example, [F36.10]) and standard numbers(s) in which they are used (for example, F2233).1.6 Abbreviated Terminology: 1.6.1 Abbreviated terminology is intended to provide uniform contractions of terms relating to infrastructure that have evolved through widespread common usage. The compilation in this standard has been prepared to avoid the occurrence of more than one abbreviated term for a given term and to avoid multiple meanings for abbreviated terms.1.6.2 The abbreviated terminology and descriptions in this standard are intended to be consistent with usage in the infrastructure industry and the standards under F36 jurisdiction. Other ASTM committees may assign a different word-phrase description to the same abbreviated terminology. In such cases, the abbreviated terms in this standard shall apply to usage in F36 standards, or if widespread misunderstanding could result from conflicting abbreviated terminology descriptions, the abbreviated terminology for the word-phrase shall not be used in F36 standards.1.6.3 Acronyms and Initialisms—A word formed from the letters or parts of words of a longer word-phrase, usually from the initial letters or parts of the words. An acronym is pronounced as a word, for example, radar for radio detection and ranging. An initialism is pronounced as a series of letters, for example, DOT for Department of Transportation.1.6.4 The acronym or initialism description is the origin word-phrase for the acronym or initialism, not a definition.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.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 The light reflected from the facial anterior teeth can be used to calculate color coordinates. Monitored over time, changes in color can be observed. These data reveal information about the efficacy of a product, treatment study, or epidemiology of tooth color. For example, clinical studies of consumer tooth whitening systems evaluate the efficacy of manufacturers’ products.5.2 The change in color of the facial surfaces of anterior teeth can be used to optimize the efficacy of tooth whitening systems. For example, the data can provide the answer the question: “What is the optimum percentage of whitening agent in a consumer tooth whitening system?”5.3 This procedure is suitable for use in research and development, marketing studies, comparative product analyses, and clinical trials.5.4 Prior research shows that a popular visual assessment method of determining tooth color, changes in tooth color, and whiteness among clinicians yields less than desirable results (1-4). These assessment tools are designated “shade guides.” They consist of tooth-shaped, synthetic objects in the form of teeth all of slightly different colors or different shades from one another. A “shade” is generally regarded as a color slightly different from a reference color (on a comparative basis). The colors of the synthetic teeth in these “shade guides” do not progress linearly as observed visually or logically in a CIE colorimetric coordinate system,5 and they are metameric to real teeth.5.5 Translucency—Human teeth are translucent and the degree of translucency varies widely between subjects. However, translucency does not vary over the short term and is not therefore a consideration in this test method.1.1 This test method covers the procedure, instrumental requirements, standardization procedures, material standards, measurement procedures, and parameters necessary to make precise measurements of in-vivo tooth color and tooth whiteness. In particular it is meant to measure the color of teeth in selected human subjects.1.2 Digital images are used to evaluate tooth color of both posterior and anterior dentition (teeth). All other non-relevant parts, such as gums, spaces, etc., must be separated from the measurement and the analysis. All localized discoloration; such as stains, inclusions, etc., may be separated from the measurement and the analysis.1.3 The broadband reflectance factors of teeth are measured. The colorimetric measurement is performed with a digital still camera while using an illuminator(s) that provides controlled illumination on the teeth. The measured data from a digital image are captured using a DSC. This test method is particularly useful for the gamut of tooth color which is:1.3.1 CIE L* from 55 to 95,1.3.2 CIE a* from 3 to 12,1.3.3 CIE b* from 8 to 25 units.1.4 The wavelengths for this test method include that portion of the visible spectrum from 400 to 700 nm.1.5 Data acquired using this test method is for comparative purposes used during clinical trials or other types of research.1.6 This test method is designed to encompass natural teeth, artificial teeth, restorations, and shade guides.Note 1—This procedure may not be applicable for all types of dental work.1.7 The apparatus, measurement procedure, data analysis technique are generic, so that a specific apparatus, measurement procedure, or data analysis technique may not be excluded.1.8 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.9 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 to determine the applicability of regulatory limitations prior to use.

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This practice covers pharmaceutical process design utilizing process analytical technology, which is integral to process development as well as post-development process optimization. It is focused on practical implementation and experimental development of process understanding. The principles in this practice are applicable to both drug substance and drug product processes. For drug products, formulation development and process development are interrelated and therefore the process design will incorporate knowledge from the formulation development. The following practices and methodologies shall be done to attain desired state: risk assessment and mitigation; continuous improvement; process fitness for purpose; intrinsic performance assessment; manufacturing strategy; data collection and formal experimental design; multivariate tools; process analyzers; and process control.1.1 This practice covers process design, which is integral to process development as well as post-development process optimization. It is focused on practical implementation and experimental development of process understanding.1.2 The term process design as used in this practice can mean:1.2.1 The activities to design a process (the process design), or1.2.2 The outcome of this activity (the designed process), or both.1.3 The principles in this practice are applicable to both drug substance and drug product processes. For drug products, formulation development and process development are interrelated and therefore the process design will incorporate knowledge from the formulation development.1.4 The principles in this practice apply during development of a new process or the improvement or redesign of an existing one, or both.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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4.1 Each Facility Rating Scale (see Figs. 1-18) in this classification provides a means to estimate the level of serviceability of a building or facility for one topic of serviceability and to compare that level against the level of any other building or facility.4.2 This classification can be used for comparing how well different buildings or facilities meet a particular requirement for serviceability. It is applicable despite differences such as location, structure, mechanical systems, age, and building shape. Further information may be found in ISO 19208.4.3 This classification can be used to estimate the amount of variance of serviceability from target or from requirement, for a single office facility, or within a group of office facilities.4.4 This classification can be used to estimate the following:4.4.1 Serviceability of an existing facility for uses other than its present use.4.4.2 Serviceability (potential) of a facility that has been planned but not yet built.4.4.3 Serviceability (potential) of a facility for which remodeling has been planned.4.5 Use of this classification does not result in building evaluation or diagnosis. Building evaluation or diagnosis generally requires a special expertise in building engineering or technology and the use of instruments, tools, or measurements.4.6 This classification applies only to facilities that are building constructions, or parts thereof. (While this classification may be useful in rating the serviceability of facilities that are not building constructions, such facilities are outside the scope of this classification.)4.7 This classification is not intended for, and is not suitable for, use for regulatory purposes, nor for fire hazard assessment nor for fire risk assessment.1.1 This classification covers matched sets of scales for classifying an aspect of the serviceability of an office facility, that is, the capability of an office facility to meet certain possible requirements for performance to support typical office equipment for information technology.1.2 Within that aspect of serviceability, each matched set of scales, shown in Figs. 1-18, are for classifying one topic of serviceability. Each topic is typically broken down into two more demand functions and supply features. Each paragraph in an Occupant Requirement Scale (see Figs. 1-18) summarizes one level of serviceability on that topic, which occupants might require. The matching entry in the Facility Rating Scale (see Figs. 1-18) is a translation of the requirement into a description of certain features of a facility which, taken in combination, indicate that the facility is likely to meet that level of required serviceability.FIG. 1 Demand Scale A.5.1 for Density of Office Computers and EquipmentFIG. 2 Supply Scale A.5.1 for Density of Office Computers and EquipmentFIG. 3 Demand Scale A.5.2.1 for Location of Available PowerFIG. 4 Supply Scale A.5.2.1 for Power DistributionFIG. 5 Demand Scale A.5.2.2 for Plug-in Points at WorkstationFIG. 6 Supply Scale A.5.2.2 for Plug-in Points per WorkstationFIG. 7 Demand Scale A.5.3 for Reliability and Quality of SupplyFIG. 8 Supply Scale A.5.3 for Reliability and Quality of SupplyFIG. 9 Demand Scale A.5.4.1 for Horizontal DistributionFIG. 10 Supply Scale A.5.4.1 for Horizontal DistributionFIG. 11 Demand Scale A.5.4.2 for RisersFIG. 12 Supply Scale A.5.4.2 for RisersFIG. 13 Demand Scale A.5.4.3 for Entrance FacilityFIG. 14 Supply Scale A.5.4.3 for Entrance FacilityFIG. 15 Demand Scale A.5.4.4 for Service to the SiteFIG. 16 Supply Scale A.5.4.4 for Service to the SiteFIG. 17 Demand Scale A.5.5 for Cable PlantFIG. 18 Supply Scale A.5.5 for Cable Plant1.3 The entries in the Facility Rating Scale (see Figs. 1-18) are indicative and not comprehensive. They are for quick scanning to estimate approximately, quickly, and economically, how well an office facility is likely to meet the needs of one or another type of occupant group over time. The entries are not for measuring, knowing, or evaluating how an office facility is performing.1.4 This classification can be used to estimate the level of serviceability of an existing facility. It can also be used to estimate the serviceability of a facility that has been planned but not yet built, such as one for which single-line drawings and outline specifications have been prepared.1.5 This classification indicates what would cause a facility to be rated at a certain level of serviceability but does not state how to conduct a serviceability rating nor how to assign a serviceability score. That information is found in Practice E1679. The scales in this classification are complimentary to, and compatible with, Practice E1679. Each requires the other.1.6 The scales are intended to identify the levels of various requirements unique to a particular user, and the serviceability (capability) of a building to meet those requirements. The scales thus supplement rather than include code requirements. It remains the responsibility of designers, builders, and building managers to meet applicable code requirements relative to their respective roles in facility design, construction, and ongoing management.1.7 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.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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Direct push LIF is used for site investigations where the delineation of petroleum hydrocarbons and other fluorophores is necessary. Generic terms for these investigations are site assessments and hazardous waste site investigations. Continuous LIF is used to provide information on the relative amounts of contamination and to provide a lithological detail of the subsurface strata. These investigations are frequently required in the characterization of hazardous waste sites. This technology provides preliminary results within minutes following the completion of each test. This allows the number, locations, and depths of subsequent tests to be adjusted in the field. Field adjustment may increase the efficiency of the investigation program. The rapid fluorescence data gathering provided by direct push LIF provides information necessary to assess the presence of contamination in soils and associated pore fluids in the field. This method allows for immediate determination of relative amounts of contamination. This allows the number, locations, and depths of subsequent activities to be adjusted in the field. Field adjustment may increase the efficiency of the investigation program. With appropriate sensors, the direct-push investigation program can provide information on soil stratigraphy and the distribution of petroleum and other fluorophores in the subsurface. This method results in minimum site disturbance and generates no cuttings that might require disposal (1). This practice is confirmed using soil samples collected at given depths to confirm the fluorescence readings using a field deployed EPA Method 418.1 (2), EPA method 8015-modified, and a modified EPA 8270 Method (3), or equivalent methodologies, as compared to the fluorescence reading from the same depth from the sensor to verify that the fluorescence correlates with the contamination. The collected samples are also tested on the probe window in the truck to ensure the sample collected is representative of the region tested in situ. This practice may not be the correct method for preliminary or supplemental investigations in all cases. Chemical and physical properties of site specific soil matrices may have an effect on site specific detection limits. Subsurface conditions affect the performance of the equipment and methods associated with the direct push method. Direct push methods are not effective in pushing in solid bedrock and are marginally effective in pushing in weathered formations. Dense gravelly tills where boulders and cobbles are present, stiff and hard clays, and cemented soil zones may cause refusal and potential probe breakage. Certain cohesive soils, depending on their moisture content, can create friction on the cone penetrometer probes which can eventually equal or exceed the static reaction force and/or the impact energy being applied. As with all direct push methods, precautions must be taken to prevent cross contamination of aquifers through migration of contaminants up or down the cone penetrometer hole. The practicing of direct push techniques may be controlled by various government regulations governing subsurface explorations. Certification or licensing regulations, or both, may in some cases be considered in establishing performance criteria. For additional information see (4-15)1.1 This practice covers the method for delineating the subsurface presence of petroleum hydrocarbons and other hydrocarbons using a fiber optic based nitrogen laser-induced fluorescence sensor system. 1.2 The petroleum hydrocarbon sensing scheme utilizes a fluorescence technique in which a nitrogen laser emits pulsed ultraviolet light. The laser, mounted on the cone penetrometer platform, is linked via fiber optic cables to a window mounted on the side of a penetrometer probe. Laser energy emitted through the window causes fluorescence in adjacent contaminated media. The fluorescent radiation is transmitted to the surface via optical cables for real-time spectral data acquisition and spectral analysis on the platform. 1.3 This sensor responds to any material that fluoresces when excited with ultraviolet wavelengths of light, largely the polycyclic aromatic, aromatic, and substituted hydrocarbons, along with a few heterocyclic hydrocarbons. The excitation energy will cause all encountered fluorophores to fluoresce, including some minerals and some non-petroleum organic matter. However, because the sensor collects full spectral information, discrimination among the fluorophores may be distinguished using the spectral features associated with the data. Soil samples should be taken to verify recurring spectral signatures to discriminate between fluorescing petroleum hydrocarbons and naturally occurring fluorophores. 1.4 This practice is used in conjunction with a cone penetrometer of the electronic type, described in Test Method D5778. 1.4.1 The direct push LIF described in this practice can provide accurate information on the characteristics of the soils and contaminants encountered in the vadose zone and the saturated zone, although it does not make a distinction between dissolved and sorbed contamination in the saturated zone. 1.5 This practice describes rapid, continuous, in-situ, real-time characterization of subsurface soil. 1.6 Direct push LIF is limited to soils that can be penetrated with the available equipment. The ability to penetrate strata is based on carrying vehicle weight, density of soil, and consistency of soil. Penetration may be limited; or, damage to sensors can occur in certain ground conditions. 1.7 This practice does not address the installation of any temporary or permanent soil, groundwater, soil vapor monitoring, or remediation devices; although, the devices described may be left in-situ for the purpose of on-going monitoring. 1.8 The values stated in inch-pound units are to be regarded as the standard. The SI units given in parentheses are for information only. 1.9 Direct push LIF environmental site characterization will often involve safety planning, administration, and documentation. This practice does not purport to address the issues of operational or site safety. 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 and health practices and determine the applicability of regulatory limitations prior to use.

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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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