4.1 The purpose of this guide is to provide guidance for selecting appropriate device size(s) and determining appropriate sample size(s) for design verification of endovascular devices. The device size(s) and sample size(s) for each design input requirement should be determined before testing. The device size(s) selected for verification testing should establish that the entire device matrix is able to achieve the design input requirements. If testing is not performed on all device sizes, justification should be provided.4.2 The sample size justification and statistical procedures used to analyze the data should be based on sound scientific principles and should be suitable for reaching a justifiable conclusion. Insufficient sample size may lead to erroneous conclusions more often than desired.4.3 Guidance regarding methodologies for determining device size selection and appropriate sample size is provided in Sections 5 and 6.1.1 This guide provides guidance for selecting an appropriate device size(s) and determining an appropriate sample size(s) (that is, number of samples) for design verification testing of endovascular devices. A methodology is presented to determine which device size(s) should be selected for testing to verify the device design adequately for each design input requirement (that is, test characteristic). Additionally, different statistical approaches are presented and discussed to help guide the developer to determine and justify sample size(s) for the design input requirement being verified. Alternate methodologies for determining device size selection and sample size selection may be acceptable for design verification.1.2 This guide applies to physical design verification testing. This guide addresses in-vitro testing; in-vivo/animal studies are outside the scope of this guide. This guide does not directly address design validation; however, the methodologies presented may be applicable to in-vitro design validation testing. Guidance for sampling related to computational simulation (for example, sensitivity analysis and tolerance analysis) is not provided. Guidance for using models, such as design of experiments (DOE), for design verification testing is not provided. This guide does not address sampling across multiple manufacturing lots as this is typically done as process validation. Special considerations are to be given to certain tests such as fatigue (see Practice E739) and shelf-life testing (see Section 8).1.3 Regulatory guidance may exist for endovascular devices that should be considered for design verification device size and sample size selection.1.4 Units—The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard.1.5 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 Advanced ceramics usually display a linear stress-strain behavior to failure. Lack of ductility combined with flaws that have various sizes and orientations typically leads to large scatter in failure strength. Strength is not a deterministic property, but instead reflects the intrinsic fracture toughness and a distribution (size and orientation) of flaws present in the material. This standard is applicable to brittle monolithic ceramics which fail as a result of catastrophic propagation of flaws. Possible rising R-curve effects are also not considered, but are inherently incorporated into the strength measurements.5.2 Two- and three-parameter formulations exist for the Weibull distribution. This standard is restricted to the two-parameter formulation.5.3 Tensile and flexural test specimens are the most commonly used test configurations for advanced ceramics. Ring-on-ring and pressure-on-ring test specimens which have multi-axial states of stress are also included. Closed-form solutions for the effective volume and effective surfaces and the Weibull material scale factor are included for these configurations. This practice also incorporates size-scaling methods for C-ring test specimens for which numerical approaches are necessary. A generic approach for arbitrary shaped test specimens or components that utilizes finite element analyses is presented in Annex A3.5.4 The fracture origins of failed test specimens can be determined using fractographic analysis. The spatial distribution of these strength-controlling flaws can be over a volume or an area (as in the case of surface flaws). This standard allows for the conversion of strength parameters associated with either type of spatial distribution. Length scaling for strength-controlling flaws located along edges of a test specimen is not covered in this practice.5.5 The scaling of strength with size in accordance with the Weibull model is based on several key assumptions (5). It is assumed that the same specific flaw type controls strength in the various specimen configurations. It is assumed that the material is uniform, homogeneous, and isotropic. If the material is a composite, it is assumed that the composite phases are sufficiently small that the structure behaves on an engineering scale as a homogeneous and isotropic body. The composite must contain a sufficient quantity of uniformly distributed, randomly oriented reinforcing elements such that the material is effectively homogeneous. Whisker-toughened ceramic composites may be representative of this type of material. This practice is also applicable to composite ceramics that do not exhibit any appreciable bilinear or nonlinear deformation behavior. This standard and the conventional Weibull strength scaling with size may not be suitable for continuous fiber-reinforced composite ceramics. The material is assumed to fracture in a brittle fashion, a consequence of stress causing catastrophic propagation of flaws. The material is assumed to be consistent (batch to batch, day to day, etc.). It is assumed that the strength distribution follows a Weibull two-parameter distribution. It is assumed that each test piece has a statistically significant number of flaws and that they are randomly distributed. It is assumed that the flaws are small relative to the specimen cross section size. If multiple flaw types are present and control strength, then strengths may scale differently for each flaw type. Consult Practice C1239 and the example in 9.1 for further guidance on how to apply censored statistics in such cases. It is also assumed that the specimen stress state and the maximum stress are accurately determined. It is assumed that the actual data from a set of fractured specimens are accurate and precise. (See Terminology E456 for definitions of the latter two terms.) For this reason, this standard frequently references other ASTM standard test methods and practices which are known to be reliable in this respect.5.6 Even if test data has been accurately and precisely measured, it should be recognized that the Weibull parameters determined from test data are in fact estimates. The estimates can vary from the actual (population) material strength parameters. Consult Practice C1239 for further guidance on the confidence bounds of Weibull parameter estimates based on test data for a finite sample size of test fractures.5.7 When correlating strength parameters from test data from one specimen geometry to a second, the accuracy of the correlation depends upon whether the assumptions listed in 5.5 are met. In addition, statistical sampling effects as discussed in 5.6 may also contribute to variations between computed and observed strength-size scaling trends.5.8 There are practical limits to Weibull strength scaling that should be considered. For example, it is implicitly assumed in the Weibull model that flaws are small relative to the specimen size. Pores that are 50 μm (0.050 mm) in diameter are volume-distributed flaws in tension or flexural strength specimens with 5 mm or greater cross section sizes. The same may not be true if the cross section size is only 100 μm.1.1 This standard practice provides methodology to convert fracture strength parameters (primarily the mean strength and the Weibull characteristic strength) estimated from data obtained with one test geometry to strength parameters representing other test geometries. This practice addresses uniaxial strength data as well as some biaxial strength data. It may also be used for more complex geometries proved that the effective areas and effective volumes can be estimated. It is for the evaluation of Weibull probability distribution parameters for advanced ceramics that fail in a brittle fashion. Fig. 1 shows the typical variation of strength with size. The larger the specimen or component, the weaker it is likely to be.1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5.1 The values stated in SI units are in accordance with IEEE/ASTM SI 10.1.6 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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4.1 This test method can be used to determine particle size distributions for material specifications, manufacturing control, and research and development work in the particle size range usually encountered in fluidizable cracking catalysts.1.1 This test method covers the determination of particle size distribution of catalyst and catalyst carrier particles using an electroconductive sensing method and is one of several valuable methods for the measurement of particle size.1.2 The range of particle sizes investigated was 20 to 150 μm (see IEEE/ASTM SI 10) equivalent spherical diameter. The technique is capable of measuring particles above and below this range. The instrument used for this method is an electric current path of small dimensions that is modulated by individual particle passage through an aperture, and produces individual pulses of amplitude proportional to the particle volume.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 The use of the body measurement information in Table 1 and Table 2 will assist manufacturers in developing patterns and garments that are consistent with the current anthropometric characteristics of the population of interest. This practice should, in turn, reduce or minimize consumer confusion and dissatisfaction related to apparel sizing (also refer to ISO 3635 Size Designation Procedures).FIG. 1 Form Front View 2-6 Little KidsFIG. 2 Form Quarter View 2-6 Little KidsFIG. 3 Form Side View 2-6 Little KidsFIG. 4 Form Back View 2-6 Little Kids1.1 These tables list body measurements of little kids’ figure type regular sizes 2-6. Although these are body measurements, they can be used as a baseline in designing apparel for little kids in this size range when considering such factors as fabric type, ease for body movement, styling, and fit.1.2 These tables list body measurements for the complete range of little kids regular sizing.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 are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.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 The use of the body measurement information in Tables 1–2 will assist manufacturers in developing patterns and garments that are consistent with the current anthropometric characteristics of the population of interest. This practice should in turn reduce or minimize consumer confusion and dissatisfaction related to apparel sizing. (Also refer to ISO 3635 Size Designation Procedures).4.2 Three-dimensional avatars depicting each of the girls’ sizes on certain measures, were created by Alvanon, Inc. and included in this standard to assist manufacturers in visualizing the posture, shape, and proportions generated by the measurements charts in the accompanying Tables. (See Figs. 1–4.)1.1 These tables list body measurements of big girl’s figure Type Regular sizes 7 through 20. Although these are body measurements, they can be used as a baseline in designing apparel for girls in this size range when considering such factors as fabric type ease for body movement, styling, and fit.1.2 These tables list body measurements for the complete range of big girl’s regular sizing.1.3 The values stated in either acceptable SI units or inch units shall be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system must be used independently of the other, without combining values in any way.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 The use of the body measurement information in Tables 1–2 will assist manufacturers in developing patterns and garments that are consistent with the current anthropometric characteristics of the population of interest. This practice should in turn reduce or minimize consumer confusion and dissatisfaction related to apparel sizing. (Also refer to ISO 3635 Size Designation Procedures).4.2 Three-dimensional avatars depicting each of the big boys’ sizes on certain measures, were created by Alvanon, Inc. and included in this standard to assist manufacturers in visualizing the posture, shape, and proportions generated by the measurements charts in the accompanying Tables. (See Figs. 1–4.)1.1 These tables list body measurements of big boy’s regular figure Type sizes 7 through 20. Although these are body measurements, they can be used as a baseline in designing apparel for boys regular in this size range when considering such factors as fabric type ease for body movement, styling, and fit.1.2 These tables list body measurements for the complete range of big boy’s sizing.1.3 The values stated in either acceptable SI units or inch units shall be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system must be used independently of the other, without combining values in any way.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 The degree of deacetylation of chitosan, as well at the molar mass and molar mass distribution, determines the functionality of chitosan in an application. For instance, functional and biological effects are highly dependent upon the composition and molar mass of the polymer.4.2 This test method describes procedures for measurement of molar mass of chitosan chlorides and glutamates, and chitosan base, although it in principle applies to any chitosan salt. The measured molar mass is that for chitosan acetate, since the mobile phase contains acetate as counter ion. This value can further be converted into the corresponding molar mass for the chitosan as a base, or the parent salt form (chloride or glutamate).4.3 Light scattering is one of very few methods available for the determination of absolute molar mass and structure, and it is applicable over the broadest range of molar masses of any method. Combining light scattering detection with size exclusion chromatography (SEC), which sorts molecules according to size, gives the ability to analyze polydisperse samples, as well as obtaining information on branching and molecular conformation. This means that both the number-average and mass-average values for molar mass and size may be obtained for most samples. Furthermore, one has the ability to calculate the distributions of the molar masses and sizes.4.4 Multi-angle laser light scattering (MALS) is a technique where measurements of scattered light are made simultaneously over a range of different angles. MALS detection can be used to obtain information on molecular size, since this parameter is determined by the angular variation of the scattered light. Molar mass may in principle be determined by detecting scattered light at a single low angle (LALLS). However, advantages with MALS as compared to LALLS are: (1) less noise at larger angles, (2) precision of measurements is improved by detecting at several angles, and (3) the ability to detect angular variation allows determination of size, branching, aggregation, and molecular conformation.4.5 Size exclusion chromatography uses columns, which are typically packed with polymer particles containing a network of uniform pores into which solute and solvent molecules can diffuse. While in the pores, molecules are effectively trapped and removed from the flow of the mobile phase. The average residence time in the pores depends upon the size of the solute molecules. Molecules that are larger than the average pore size of the packing are excluded and experience virtually no retention; these are eluted first, in the void volume of the column. Molecules, which may penetrate the pores will have a larger volume available for diffusion, they will be retained in the column for a time dependent upon their molecular size, with smaller molecules eluting after larger molecules.4.6 For polyelectrolytes, dialysis against the elution buffer has been suggested, in order to eliminate Donnan-type artifacts in the molar mass determination by light scattering (1, 2).5 However, in the present method, the size exclusion chromatography step preceding the light scatter detection is an efficient substitute for a dialysis step. The sample is separated on SEC columns with large excess of elution buffer for 30 to 40 min, and it is therefore in full equilibrium with the elution buffer when it reaches the MALS detector.1.1 This test method covers the determination of the molar mass of chitosan and chitosan salts intended for use in biomedical and pharmaceutical applications as well as in tissue engineered medical products (TEMPs) by size exclusion chromatography with multi-angle laser light scattering detection (SEC-MALS). A guide for the characterization of chitosan salts has been published as Guide F2103.1.2 Chitosan and chitosan salts used in TEMPs should be well characterized, including the molar mass and polydispersity (molar mass distribution) in order to ensure uniformity and correct functionality in the final product. This test method will assist end users in choosing the correct chitosan for their particular application. Chitosan may have utility as a scaffold or matrix material for TEMPs, in cell and tissue encapsulation applications, and in drug delivery formulations.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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