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5.1 This practice establishes the procedure to determine adjustment factors that account for the isolated effects of fire-retardant treatment on plywood roof sheathing. These effects are established relative to performance of untreated plywood. This practice uses data from reference thermal-load cycles designed to simulate temperatures in sloped roofs of common design to evaluate products for 50 iterations.5.2 This practice applies to material installed using construction practices recommended by the fire retardant chemical manufacturers that include avoiding exposure to precipitation, direct wetting, or regular condensation. This practice is not meant to apply to buildings with significantly different designs than those described in 1.3.5.3 Test Method D5516 caused thermally induced strength losses in laboratory simulations within a reasonably short period. The environmental conditions used in the laboratory-activated chemical reactions that are considered to be similar to those occurring in the field. This assumption is the fundamental basis of this practice.1.1 This practice covers procedures for calculating adjustment factors that account for the effects of fire-retardant treatment on bending strength of plywood roof sheathing. The adjustment factors calculated in accordance with this practice are to be applied to design values for untreated plywood in order to determine design values for fire-retardant-treated plywood used as sheathing in roof systems. The methods establish the effect of treatment based upon matched bending strength testing of materials with and without treatment after exposure at elevated temperatures.NOTE 1: This analysis focuses on the relative performance of treated and untreated materials tested after equilibrating to ambient conditions following a controlled exposure to specified conditions of high temperature and humidity. Elevated temperature, moisture, load duration, and other factors typically accounted for in the design of untreated plywood must also be considered in the design of fire-retardant-treated plywood roof sheathing, but are outside the scope of the treatment adjustments developed under this practice.1.2 It is assumed that the procedures will be used for fire-retardant-treated plywood installed using appropriate construction practices recommended by the fire retardant chemical manufacturers, which include avoiding exposure to precipitation, direct wetting, or regular condensation.1.3 This practice uses thermal load profiles reflective of exposures encountered in normal service conditions in a wide variety of continental United States climates. The heat gains, solar loads, roof slopes, ventilation rates, and other parameters used in this practice were chosen to reflect common sloped roof designs. This practice is applicable to roofs of 3 in 12 or steeper slopes, to roofs designed with vent areas and vent locations conforming to national standards of practice, and to designs in which the bottom side of the sheathing is exposed to ventilation air. These conditions may not apply to significantly different designs and therefore this practice may not apply to such designs.1.4 Information and a brief discussion supporting the provisions of this practice are in the Commentary in the appendix. A large, more detailed, separate Commentary is also available from ASTM.21.5 The methodology in this practice is not meant to account for all reported instances of fire-retardant plywood undergoing premature heat degradation.1.6 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.1.7 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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1.1 The purpose of this guide is to provide the secondary ion mass spectrometry (SIMS) analyst with two procedures for determining relative sensitivity factors (RSFs) from ion implanted external standards. This guide may be used for obtaining the RSFs of trace elements (<1 atomic %) in homogeneous (chemically and structurally) specimens. This guide is useful for all SIMS instruments.1.2 This guide does not describe procedures for obtaining RSFs for major elements (>1 atomic %). In addition, this guide does not describe procedures for obtaining RSFs from implants in heterogeneous (either laterally or in-depth) specimens.1.3 The values stated in SI units are to be regarded as 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.

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定价： 590元 / 折扣价： 502 元 加购物车

5.1 Integrating ergonomic principles into new occupational systems may help businesses develop processes that do not exceed worker capabilities and limitations.5.2 Jobs and tasks that conform to worker capabilities and limitations may be performed more efficiently, safely, and consistently than those that do not.5.3 The application of ergonomic principles to the processes involved in occupational systems may help avoid system failures and inefficiencies.5.4 The integration of ergonomic principles at the earliest stages of process concept and design may facilitate appropriate design, layout, and allocation of resources and may reduce or eliminate the necessity for later redesign that could have been foreseen.5.5 Designing jobs that fit the capabilities of larger population segments may increase an organization's accessibility to the available labor pool.5.6 The integration of ergonomic principles into occupational systems may increase profit by lowering direct and indirect costs associated with preventable losses, injuries, and illnesses.5.7 The bibliography contains a list of reference materials that may be useful in particular applications. All appendixes are nonmandatory.1.1 This guide is intended to assist in the integration of ergonomic principles into the design and planning of new occupational systems from the earliest design stages through implementation. Doing so may reduce or eliminate the necessity for later redesign that could have been foreseen.1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Fire-retardant-treatments are used to reduce the flame-spread characteristics of wood. Chemicals and redrying conditions employed in treatments are known to modify the strength properties of the wood product being treated. This practice establishes the procedures for determining adjustment factors that account for the isolated effects of fire-retardant treatment on design properties of lumber. These effects are established relative to performance of untreated lumber.5.2 The effect of fire-retardant treatments on the strength of lumber used in roof framing applications is time related. In this practice, the cumulative effect on strength of annual thermal loads from all temperature bins is increased 50 times to establish treatment adjustment factors for fire-retardant treated lumber roof framing.5.3 The procedures of Test Method D5664 employ an elevated temperature intended to produce strength losses in a short period of time. Although the exposure is much more severe than that which occurs in an actual roof system, the chemical reactions that occur in the laboratory test are considered to be the same as those occurring over long periods of time in the field.5.4 Treatment adjustment factors developed under this practice apply to lumber installed in accordance with construction practices recommended by the fire-retardant chemical manufacturer which include avoidance of direct wetting, precipitation or frequent condensation. Application of this practice is limited to roof applications with design consistent with 1.3.1.1 This practice covers procedures for calculating adjustment factors that account for the effects of fire-retardant treatment on design properties of lumber. The adjustment factors calculated in accordance with this practice are to be applied to design values for untreated lumber in order to determine design values for fire-retardant-treated lumber used at ambient temperatures [service temperatures up to 100 °F (38 °C)] and as framing in roof systems.NOTE 1: This analysis focuses on the relative performance of treated and untreated materials tested after equilibrating to ambient conditions following a controlled exposure to specified conditions of high temperature and humidity. Elevated temperature, moisture, load duration, and other factors typically accounted for in the design of untreated lumber must also be considered in the design of fire-retardant-treated lumber, but are outside the scope of the treatment adjustments developed under this practice.1.2 These adjustment factors for the design properties in bending, tension parallel to grain, compression parallel to grain, horizontal shear, and modulus of elasticity are based on the results of strength tests of matched treated and untreated small clear wood specimens after conditioning at nominal room temperatures [72 °F (22 °C)] and of other similar specimens after exposure at 150 °F (66 °C). The test data are developed in accordance with Test Method D5664. Guidelines are provided for establishing adjustment factors for the property of compression perpendicular to grain and for connection design values.1.3 Treatment adjustment factors for roof framing applications are based on thermal load profiles for normal wood roof construction used in a variety of climates as defined by weather tapes of the American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc. (ASHRAE).2 The solar loads, moisture conditions, ventilation rates, and other parameters used in the computer model were selected to represent typical sloped roof designs. The thermal loads in this practice are applicable to roof slopes of 3 in 12 or steeper, to roofs designed with vent areas and vent locations conforming to national standards of practice and to designs in which the bottom side of the roof sheathing is exposed to ventilation air. For designs that do not have one or more of these base-line features, the applicability of this practice needs to be documented by the user.1.4 The procedures of this practice parallel those given in Practice D6305. General references and commentary in Practice D6305 are also applicable to this practice.1.5 The values stated in inch-pound units are to be regarded as standard. The SI units listed in parentheses 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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5.1 ASTM standard gas chromatographic methods for the analysis of petroleum products require calibration of the gas chromatographic system by preparation and analysis of specified reference mixtures. Frequently, minimal information is given in these methods on the practice of calculating calibration or response factors. Test Methods D2268, D2427, D2804, D2998, D3329, D3362, D3465, D3545, and D3695 are examples. The present practice helps to fill this void by providing a detailed reference procedure for calculating response factors, as exemplified by analysis of a standard blend of C6 to C11 n-paraffins using n-C12 as the diluent.5.2 In practice, response factors are used to correct peak areas to a common base prior to final calculation of the sample composition. The response factors calculated in this practice are “multipliers” and prior to final calculation of the results the area obtained for each compound in the sample should be multiplied by the response factor determined for that compound.5.3 It has been determined that values for response factors will vary with individual installations. This may be caused by variations in instrument design, columns, and experimental techniques. It is necessary that chromatographs be individually calibrated to obtain the most accurate data.1.1 This practice covers a procedure for calculating gas chromatographic response factors. It is applicable to chromatographic data obtained from a gaseous mixture or from any mixture of compounds that is normally liquid at room temperature and pressure or solids, or both, that will form a solution with liquids. It is not intended to be applied to those compounds that react in the chromatograph or are not quantitatively eluted. Normal C6 through C11 paraffins have been chosen as model compounds for demonstration purposes.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, 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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3.1 This guide may be used to provide a consistent method for determining load ratios for technical rescue equipment and systems.3.2 Use of this guide will help to maintain clearer, more consistent calculation and reporting of load ratios.3.3 It should be acknowledged that, while component load ratios are fairly straightforward to calculate, they are of limited value for estimating system load ratios. System load ratios are usually desired for field applications, but are more difficult to calculate accurately.1.1 This guide covers the general concept of determining safety factors for technical rescue equipment and systems.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 In the event of any conflict between the text of this guide and any references cited, the text of this guide takes preference.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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定价： 590元 / 折扣价： 502 元 加购物车

4.1 The procedure and tables presented in this practice are based on the use of the Weibull distribution in acceptance sampling inspection. Details of this work, together with tables of sampling plans of other forms, have been published previously. See Refs (1-3).4 Since the basic computations required have already been made, it has been quite easy to provide these new factors. No changes in method or details of application have been made over those described in the publications referenced above. For this reason, the text portion of this report has been briefly written. Readers interested in further details are referred to these previous publications. Other sources of material on the underlying theory and approach are also available (4-7).4.2 The procedure to be used is essentially the same as the one normally used for attribute sampling inspection. The only difference is that sample items are tested for life or survival instead of for some other property. For single sampling, the following are the required steps:4.2.1 Using the tables of factors provided in Annex A1, select a suitable sampling inspection plan from those tabulated in Practice E2234.4.2.2 Draw at random a sample of items of the size specified by the selected Practice E2234 plan.4.2.3 Place the sample of items on life test for the specified period of time, t.4.2.4 Determine the number of sample items that failed during the test period.4.2.5 Compare the number of items that failed with the number allowed under the selected Practice E2234 plan.4.2.6 If the number that failed is equal to or less than the acceptable number, accept the lot; if the number failing exceeds the acceptable number, reject the lot.4.3 Both the sample sizes and the acceptance numbers used are those specified by Practice E2234 plans. It will be assumed in the section on examples that single sampling plans will be used. However, the matching double sampling and multiple sampling plans provided in MIL-STD-105 can be used if desired. The corresponding sample sizes and acceptance and rejection numbers are used in the usual way. The specified test truncation time, t, must be used for all samples.4.4 The probability of acceptance for a lot under this procedure depends only on the probability of a sample item failing before the end of the test truncation time, t. For this reason, the actual life at failure need not be determined; only the number of items failing is of interest. Life requirements and test time specifications need not necessarily be measured in chronological terms such as minutes or hours. For example, the life measure may be cycles of operation, revolutions, or miles of travel.4.5 The underlying life distribution assumed in this standard is the Weibull distribution (note that the exponential distribution is a special case of the Weibull). The Weibull model has three parameters. One parameter is a scale or characteristic life parameter. For these plans and procedures, the value for this parameter need not be known; the techniques used are independent of its magnitude. A second parameter is a location or “guaranteed life” parameter. In these plans and procedures, it is assumed that this parameter has a value of zero and that there is some risk of item failure right from the start of life. If this is not the case for some applications, a simple modification in procedure is available. The third parameter, and the one of importance, is the shape parameter, β.5 The magnitude of the conversion factors used in the procedures described in this report depends directly on the value for this parameter. For this reason, the magnitude of the parameter shall be known through experience with the product or shall be estimated from past research, engineering, or inspection data. Estimation procedures are available and are outlined in Ref (1).4.6 For the common case of random chance failures with the failure rate constant over time, rather than failures as a result of “infant mortality” or wearout, a value of 1 for the shape parameter shall be assumed. With this parameter value, the Weibull distribution reduces to the exponential. Tables of conversion factors are provided in Annex A1 for 15 selected shape parameter values ranging from 1/2 to 10, the range commonly encountered in industrial and technical practice. The value 1, used for the exponential case, is included. Factors for other required shape parameter values within this range may be obtained approximately by interpolation. A more complete discussion of the relationship between failure patterns and the Weibull parameters can be found in Refs (1-3).4.7 One possible acceptance criterion is the mean life for items making up the lot (μ). Mean life conversion factors or values for the dimensionless ratio 100t/μ have been determined to correspond to or replace all the p' or percent defective values associated with Practice E2234 plans. In this factor, t represents the specified test truncation time and μ the mean item life for the lot. For reliability or life-length applications, these factors are used in place of the corresponding p' values normally used in the use of Practice E2234 plans for attribute inspection of other item qualities. The use of these factors will be demonstrated by several examples (see Sections 5, 7, and 9).4.8 Annex Table 1A lists, for each selected shape parameter value, 100t/μ ratios for each of the Practice E2234 AQL [p'(%)] values. With acceptance inspection plans selected in terms of these ratios, the probability of acceptance will be high for lots whose mean life meets the specified requirement. The actual probability of acceptance will vary from plan to plan and may be read from the associated operating characteristic curves supplied in MIL-STD-105. The curves are entered by using the corresponding p'(%) value. Annex Table 1B lists 100t/μ ratios at the LQL for the quality level at which the consumer's risk is 0.10. Annex Table 1C lists corresponding 100t/μ ratios for a consumer's risk of 0.05.4.8.1 These ratios are to be used directly for the usual case for which the value for the Weibull location or threshold parameter (γ) can be assumed as zero. If γ is not zero but has some other known value, all that shall be done is to subtract the value for γ from t to get t0 and from m to get m0. These transformed values, t 0 and m0, are then employed in the use of the tables and for all other computations. A solution in terms of m0 and t0 can then be converted back to actual or absolute values by adding the value for γ to each.AbstractThis practice presents a procedure and related tables of factors for adapting Practice E2234 (equivalent to MIL-STD105) sampling plans to acceptance sampling inspection when the item quality of interest is life length or reliability. Factors are provided for three alternative criteria for lot evaluation: mean life, hazard rate, and reliable life. Inspection of the sample is by attributes with testing truncated at the end of some prearranged period of time. The Weibull distribution, together with the exponential distribution as a special case, is used as the underlying statistical model. The procedure and tables presented in this practice are based on the use of the Weibull distribution in acceptance sampling inspection.1.1 This practice presents a procedure and related tables of factors for adapting Practice E2234 (equivalent to MIL-STD-105) sampling plans to acceptance sampling inspection when the item quality of interest is life length or reliability. Factors are provided for three alternative criteria for lot evaluation: mean life, hazard rate, and reliable life. Inspection of the sample is by attributes with testing truncated at the end of some prearranged period of time. The Weibull distribution, together with the exponential distribution as a special case, is used as the underlying statistical model.1.2 A system of units is not specified by this practice.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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