定价： 333元 / 折扣价： 284 元 加购物车

定价： 319元 / 折扣价： 272 元 加购物车

5.1 Thermal conductivity measurements on small insulation specimens are important during new product development processes or when larger specimens cannot be collected during forensic investigation (that is, failure analysis) (1, 2).5.2 Numerous research projects have recently been initiated to develop insulation materials that have very high thermal resistivities (greater than 83 (m K)/W). Projects ranging from coatings to improve the thermal performance of single pane/layer glazing systems to the development of novel insulation products for building envelopes are being undertaken (1-4). All these projects have struggled in the development of new material technologies due to the difficulty associated with the measurement of thermal conductivity of small sections (approximately 0.025 m by 0.025 m) of high thermal resistance materials. As new materials are being developed, the size of each test specimen impacts the cost of development. Most of the existing test equipment and the methods do not align with the researcher’s need; the equipment requires a large specimen size is time consuming, and expensive to produce.5.3 This practice provides a standardized procedure to enable the thermal characterization of small specimens of insulation materials. Accurate, and reliable thermal metrology to assess thermal properties of new insulation materials, such as novel very low thermal conductivity (< 0.01 W/ (m K)) nanomaterials or bio-based foam insulations, in small material sample sections, and minimal data analysis requirements is the desired outcome of this practice.5.4 The ratio of the area of the specimen and the heat flux transducer has a significant impact on the uncertainty of the results obtained from this practice. As the specimen area decreases this ratio decreases, a smaller percentage of the total heat flow is associated with the unknown specimen. Information from the literature (4) shows that some heat-flow-meter apparatus, generally not available commercially and used by the research laboratories only, can be modified to change out the heat flux transducer so that transducers of varying sizes can be deployed. The observations presented in Fig. 2 were obtained from the measurements done by such a heat-flow-meter apparatus that was modified to change out the heat flux transducer. Fig. 2 demonstrates the significance of the ratio of the area of the specimen and the heat flux transducer on the accuracy of the thermal conductivity measurement using this Practice. This exercise is not a required part of this Practice and Fig. 2 is for information only.FIG. 2 Example of a data set obtained from 0.010 m2 (that is, 0.10 m × 0.10 m) heat flux transducer (heat flow) exploring the uncertainty (that is, difference between full size XPS specimen and smaller XPS specimen placed inside the mask) of varying thicknesses, 0.005 m, 0.010 m, and 0.020 m1.1 This practice covers the measurement of steady state thermal transmission properties of the small flat slab thermal insulation specimen using a heat-flow-meter apparatus.1.2 This practice provides a supplemental procedure for use in conjunction with Test Method C518 for testing a small specimen. This practice is limited to only small specimens and, in all other particulars, the requirements of Test Method C518 apply.1.3 This practice characterizes small specimens having lateral dimensions less than the lateral dimensions of the heat flux transducer used to measure the heat flow. The procedure in Test Method C518 shall be used for specimens having lateral dimensions equal to or larger than the lateral dimensions of the heat flux transducer.NOTE 1: The lower limit for specimen size is typically determined by the user for their particular material. As an example, Ref. (1)2 established a lower limit for specimen dimensions of 0.1 m by 0.1 m for several different thermal insulation materials for a 0.3 m by 0.3 m heat-flow-meter apparatus having a heat flux transducer 0.15 m by 0.15 m.1.4 This practice is intended only for research purposes, in particular, when larger specimens are unavailable. This practice shall not be used in conjunction with Test Method C518 for certification testing of products; compliance with ASTM Specifications; or compliance with regulatory or building code requirements.1.5 The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this practice.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.

定价： 590元 / 折扣价： 502 元 加购物车

5.1 Factors that may influence the thermal-transmission properties of a specimen of material are described in Practice C1045 and the Precision and Bias section of Test Method C177.5.2 Because of the required test conditions prescribed by this test method, it shall be recognized that the thermal properties obtained will not necessarily apply without modification to all conditions of service. As an example, this test method normally provides that the thermal properties shall be obtained on specimens that do not contain moisture, although in service such conditions may not be realized. Even more basic is the dependence of the thermal properties on variables such as mean temperature and temperature difference.5.3 When a new or modified design of apparatus is evolved, tests shall be made on at least two sets of differing material of known long-term thermal stability. Tests shall be made for each material at a minimum of two different mean temperatures within the operating range of each. Any differences in results should be carefully studied to determine the cause and then be removed by appropriate action. Only after a successful verification study on materials having known thermal properties traceable to a recognized national standards laboratory shall test results obtained with this apparatus be considered to conform with this test method. Periodic checks of apparatus performance are recommended.5.4 The thermal transmission properties of many materials depend upon the prior thermal history. Care must be exercised when testing such specimens at a number of conditions so that tests are performed in a sequence that limits such effects on the results.5.5 Typical uses for the thin-heater apparatus include the following:5.5.1 Product development and quality control applications.5.5.2 Measurement of thermal conductivity at desired mean temperatures.5.5.3 Thermal properties of specimens that are moist or close to melting point or other critical temperature (see Note 1).NOTE 1: Apparatus of the type covered by this test method apply to the study of thermal properties of specimens containing moisture because of the use of small temperature differences and the low thermal capacity of the heat source.5.5.4 Determination of thermal properties of relatively high R value insulation samples with large apparatuses. In the case of the metal-screen heater apparatus, samples with thicknesses up to 15 cm can be measured.1.1 This test method covers the determination of the steady-state thermal transmission properties of flat-slab specimens of thermal insulation using a thin heater of uniform power density having low lateral heat flow. A thin heater with low lateral thermal conductance can reduce unwanted lateral heat flow and avoid the need for active-edge guarding.1.2 This primary test method of thermal-transmission measurement describes a principle, rather than a particular apparatus. The principle involves determination of the thermal flux across a specimen of known thickness and the temperatures of the hot and cold faces of the specimen.1.3 Considerable latitude is given to the designer of the apparatus in this test method; since a variety of designs is possible, a procedure for qualifying an apparatus is given in 5.3.1.4 The specimens must meet the following conditions if thermal resistance or thermal conductance of the specimen is to be determined by this test method2:1.4.1 The portion of the specimen over the isothermal area of the heater must accurately represent the whole specimen.1.4.2 The remainder of the specimen should not distort the heat flow in that part of the specimen defined in 1.4.1.1.4.3 The specimen shall be thermally homogeneous such that the thermal conductivity is not a function of the position within the sample, but rather may be a function of direction, time, and temperature. The specimen shall be free of holes, of high-density volumes, and of thermal bridges between the test surfaces or the specimen edges.1.4.4 Test Method C177 describes tests that can help ascertain whether conditions of 1.4 are satisfied. For the purposes of this test method, differences in the measurements of less than 2 % may be considered insignificant, and the requirements fulfilled.1.5 The specimens shall meet one of the following requirements, in addition to those of 1.4.1.5.1 If homogeneous materials as defined in Terminology C168 are tested, then the thermal resistivity and thermal conductivity can be determined by this test method.1.5.2 If materials which are layered or otherwise thermally inhomogeneous are tested, thermal resistance and thermal conductance can be determined by this test method.1.6 Two versions of thin-heater apparatus using the same principle of the standard are described in Annex A1 and Annex A2. They are similar in concept but differ in size and construction, and hence warrant separate descriptions for each design. This test method in no way limits the size of the thin-heater element. One of the units described uses a thin metal foil, while the other uses a metal screen as the heat source. The smaller, foil apparatus is designed to make rapid measurements of heat transmission through specimens as thin as 0.5 cm and as thick as 2 cm; however, an apparatus using a foil heater could be designed to measure much thicker materials, if desired. The larger, screen apparatus is designed to measure specimens with thicknesses between 3 and 15 cm, where the exact limits depend on the thermal resistance of the specimens. Both apparatuses use thermocouples for measuring temperature, but other temperature-sensing systems can be used.1.7 This test method covers the theory and principles of the measurement technique. It does not provide details of construction other than those required to illustrate two devices which meet the prescribed requirements. Detailed information is available in References (1-23)3 and the Adjunct.1.8 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.10 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.

定价： 590元 / 折扣价： 502 元 加购物车

This method provides for the determination of the steady state thermal resistance of a fabric or layers of fabrics and for the determination of the temperature regulating factor (TRF) as defined below. This test method is considered satisfactory for acceptance testing of commercial shipments because the round robin testing shows high precision and no bias for testing of textile fabrics and foams.5.1.1 If there are differences of practical significance between reported test results for two laboratories (or more), comparative test should be performed to determine if there is a statistical bias between them, using competent statistical assistance. As a minimum, use the samples for such a comparative test that are as homogeneous as possible, drawn from the same lot of material as the samples that resulted in disparate results during initial testing and randomly assigned in equal numbers to each laboratory. The test results from the laboratories involved should be compared using a statistical test for unpaired data, a probability level chosen prior to the testing series. If bias is found, either its cause must be found and corrected, or future test results for that material must be adjusted in consideration of the known bias.This test method is useful in quality and cost control during manufacture. It can be used to establish criteria for establishing thermal and comfort parameters for textiles particularly used in the clothing industry.1.1 This test method covers the determination of the overall thermal transmission coefficient due to conduction for dry specimens of textile fabrics, battings, and other materials and the determination of the temperature regulating factor (TRF) defined below.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 and health practices and determine the applicability of regulatory limitations prior to use.

定价： 0元 / 折扣价： 0 元

4.1 This practice details the test specimen sizes and test conditions, namely, the room-side and weather-side air temperatures, and the surface heat transfer coefficients for both sides of the test specimen, when testing fenestration products in accordance with Test Method C1199.4.2 The thermal transmittance and conductance of a specimen are affected by its size and three-dimensional geometry. Tests should therefore be conducted using the specimen sizes recommended in 5.1. Should the specimen size differ from those given in 5.1, the actual size shall be reported in the test report.4.3 Many factors can affect the thermal performance of a fenestration system, including deflections of sealed glazing units. Care should be exercised to maintain the original physical condition of the fenestration system and while installing it in the surround panel.4.4 The thermal transmittance and conductance results obtained do not, and are not intended, to reflect performances expected from field installations since they do not account for solar radiation and air leakage effects. The thermal transmittance and conductance results are taken from specified laboratory conditions and are to be used only for fenestration product comparisons and as input to thermal performance analyses that also include solar and air leakage effects.1.1 This practice covers standard test specimen sizes and test conditions as well as the calculation and presentation of the thermal transmittance and conductance data measured in accordance with Test Method C1199. The standard sizes and conditions are to be used for fenestration product comparison purposes. The specifier may choose other sizes and conditions for product development or research purposes.1.2 This practice deals with the determination of the thermal properties of a fenestration system installed vertically without the influences of solar heat gain and air leakage effects.NOTE 1: To determine air leakage effects of fenestration systems, Test Method E283/E283M or E1424 should be referenced.NOTE 2: See Appendix X1 regarding garage doors and rolling doors.1.3 This practice specifies the procedure for determining the standardized thermal transmittance of a fenestration test specimen using specified values of the room-side and weather-side surface heat transfer coefficients, hh and hc, respectively.1.4 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.1.5 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.

定价： 646元 / 折扣价： 550 元 加购物车

Recent results have demonstrated that direct measurements of unsaturated transport parameters, for example, hydraulic conductivity, vapor diffusivity, retardation factors, thermal and electrical conductivities, and water potential, on subsurface materials and engineered systems are essential for defensible site characterization needs of performance assessment as well as restoration or disposal strategies. Predictive models require the transport properties of real systems that can be difficult to obtain over reasonable time periods using traditional methods. Using a SSC-UFA greatly decreases the time required to obtain direct measurements of hydraulic conductivity on unsaturated systems and relatively impermeable materials. Traditionally, long times are required to attain steady-state conditions and distributions of water because normal gravity does not provide a large enough driving force relative to the low conductivities that characterize highly unsaturated conditions or highly impermeable saturated systems (Test Method D5084). Pressure techniques sometimes can not be effective for measuring unsaturated transport properties because they do not provide a body force and cannot act on the entire specimen simultaneously unless the specimen is saturated or near-saturated. A body force is a force that acts on every point within the system independently of other forces or properties of the system. High pressures used on saturated systems often induce fracturing or grain rearrangements and cause compaction as a result of high-point stresses that are generated within the specimen. A SSC-UFA does not produce such high-point stresses.There are specific advantages to using centrifugal force as a fluid driving force. It is a body force similar to gravity and, therefore, acts simultaneously over the entire system and independently of other driving forces, for example, gravity or matric potential. Additionally, in a SSC-UFA the acceleration can dominate any matric potential gradients as the Darcy driving force. The use of steady-state centrifugation to measure steady-state hydraulic conductivities has recently been demonstrated on various porous media (1,2).Several issues involving flow in an acceleration field have been raised and addressed by previous and current research (1,4). These studies have shown that compaction from acceleration is negligible for subsurface soils at or near their field densities. Bulk densities in these specimens have remained constant (±0.1 g/cm3) because the specimens are already compacted more than the acceleration can affect them. The notable exception is structured soils. Special arrangements must be made to preserve their densities, for example, the use of speeds not exceeding specific equivalent stresses. As an example, for most SSC-UFA specimen geometries, the equivalent pressure in the specimen at a rotation speed of 2500 rpm is about 2 bar. If the specimen significantly compacts under this pressure, a lower speed must be used. Usually, only very fine soils at dry bulk densities less than 1.2 g/cm3 are a problem. Whole rock, grout, ceramics, or other solids are completely unaffected by these accelerations. Precompaction runs up to the highest speed for that run are performed in the SSC-UFA prior to the run to observe any compaction effects.Three-dimensional deviations of the driving force as a function of position in the specimen are less than a factor of two. Theoretically, the situation under which unit gradient conditions are achieved in a SSC-UFA, in which the change in the matric potential with radial distance equals zero (dψ/dr = 0), is best at higher water flux densities, higher speeds, or coarser grain-size, or combination thereof. This is observed in potential gradient measurements in the normal operational range where dψ/dr = 0. The worst case occurs at the lowest water flux densities in the finest-grained materials (1).There is no sidewall leakage problem in the SSC-UFA for soils. The centrifugal force maintains a good seal between the specimen and the wall. As the specimen desaturates, the increasing matric potential (which still operates in all directions although there is no potential gradient) keeps the water within the specimen, and the acceleration (not being a pressure) does not force water into any larger pore spaces such as along a wall. Therefore, capillary phenomena still hold in the SSC-UFA, a fact which is especially important for fractured or heterogeneous media (2). Cores of solid material such as rock or concrete, are cast in epoxy sleeves as their specimen holder, and this also prevents sidewall leakage.The SSC-UFA can be used in conjunction with other methods that require precise fixing of the water content of a porous material. The SSC-UFA is used to achieve the steady-state water content in the specimen and other test methods are applied to investigate particular problems as a function of water content. This has been successful in determining diffusion coefficients, vapor diffusivity, electrical conductivity, monitoring the breakthrough of chemical species (retardation factor), pore water extraction, solids characterization, and other physical or chemical properties as functions of the water content (2,5).Hydraulic conductivity can be very sensitive to the solution chemistry, especially when specimens contain expandable, or swelling, clay minerals. Water should be used that is appropriate to the situation, for example, groundwater from the site from which the specimen was obtained, or rainwater if an experiment is being performed to investigate infiltration of precipitation into a disposal site. Appropriate antimicrobial agents should be used to prevent microbial effects within the specimen, for example, clogging, but should be chosen with consideration of any important chemical issues in the system. A standard synthetic pore water solution, similar to the solution expected in the field, is useful when it is difficult to obtain field water. Distilled or deionized water is generally not useful unless the results are to be compared to other tests using similar water or is specified in pertinent test plans, ASTM test methods, or EPA procedures. Distilled water can dramatically affect the conductivity of soil and rock specimens that contain clay minerals, and can induce dissolution/precipitation within the specimen.This test method establishes a dynamic system, and, as such, the steady-state water content is usually higher than that which is attained during a pressure plate or other equilibrium method that does not have flow into the specimen during operation. This is critical when using either type of data for modeling purposes. This test method does not measure water vapor transport or molecular diffusion of water, both of which become very significant at low conductivities, and may actually dominate when hydraulic conductivities drop much below 10–10 cm/s.The quality of the result produced by this test method depends upon 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 and sampling. Users of this test method are cautioned that compliance with Practice D3740 does not in itself ensure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.1.1 This test method covers the determination of the hydraulic conductivity, or the permeability relative to water, of any porous medium in the laboratory, in particular, the hydraulic conductivity for water in subsurface materials, for example, soil, sediment, rock, concrete, and ceramic, either natural or artificial, especially in relatively impermeable materials or materials under highly unsaturated conditions. This test method covers determination of these properties using any form of steady-state centrifugation (SSC) in which fluid can be applied to a specimen with a constant flux or steady flow during centrifugation of the specimen. This test method only measures advective flow on core specimens in the laboratory.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 may involve hazardous materials, operations, and equipment. 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 details the calibration and testing procedures and necessary additional temperature instrumentation required in applying Test Method C1363 to measure the thermal transmittance of fenestration systems mounted vertically in the thermal chamber. 4.2 The thermal transmittance of a test specimen is affected by its size and three-dimensional geometry. Care must be exercised when extrapolating to product sizes smaller or larger than the test specimen. Therefore, it is recommended that fenestration systems be tested at the recommended sizes specified in Practice E1423 or NFRC 100. 4.3 Since both temperature and surface heat transfer coefficient conditions affect results, use of recommended conditions will assist in reducing confusion caused by comparing results of tests performed under dissimilar conditions. Standardized test conditions for determining the thermal transmittance of fenestration systems are specified in Practice E1423 and Section 6.2. The performance of a test specimen measured at standardized test conditions is potentially different than the performance of the same fenestration product when installed in the wall of a building located outdoors. Standardized test conditions often represent extreme summer or winter design conditions, which are potentially different than the average conditions typically experienced by a fenestration product installed in an exterior wall. For the purpose of comparison, it is essential to calibrate with surface heat transfer coefficients on the Calibration Transfer Standard (CTS) which are as close as possible to the conventionally accepted values for building design; however, this procedure can be used at other conditions for research purposes or product development. 4.4 Similarly, it would be desirable to have a surround panel that closely duplicates the actual wall where the fenestration system would be installed. Since there are such a wide variety of fenestration system openings in North American residential, commercial and industrial buildings, it is not feasible to select a typical surround panel construction for installing the fenestration system test specimen. Furthermore, for high resistance fenestration systems installed in fenestration opening designs and constructions that have thermal bridges, the large relative amount of heat transfer through the thermal bridge will cause the relatively small amount of heat transfer through the fenestration system to have a larger than desirable error. For this reason, the Calibration Transfer Standard and test specimen are installed in a homogeneous surround panel constructed from materials having a relatively high thermal resistance. Installing the test specimen in a relatively high thermal resistance surround panel places the focus of the test on the fenestration system thermal performance alone. Therefore, it is important to recognize that the thermal transmittance results obtained from this test method are for ideal laboratory conditions, and should only be used for fenestration product comparisons unless the thermal bridge effects that have the potential to occur due to the specific design and construction of the fenestration system opening are included in the analysis. 4.5 This test method does not include procedures to determine the heat flow due to either air movement through the specimen or solar radiation effects. As a consequence, the thermal transmittance results obtained do not reflect performances that are expected from field installations. It is possible to use the results from this test method as input to annual energy performance analyses which include solar, and air leakage effects to get a better estimate of how the test specimen would perform when installed in an actual building. To determine the Solar Heat Gain Coefficient of fenestration products, refer to NFRC 200. To determine air leakage for windows and doors, refer to Test Methods E283 and E783. 4.6 It is important to recognize that the thermal transmittance, US, value determined in Section 8 is the only true experimental measurement result of this test method. The “standardized” thermal transmittance value, UST, obtained by either the Calibration Transfer Standard (CTS) or Area Weighting (AW) methods described in Section 8 include adjustments to the thermal transmittance value bases on results from calibration runs described in Section 6. The standardized thermal transmittance is useful for two reasons; it facilitates comparison of test results between different laboratories with different thermal chamber geometries and configurations, and it improves the comparison between test results and computer simulation results. Due to the differences in size, geometry, and climate chamber air flow permitted by this test method, Test Method C1363, and Practice E1423, there can be significant variations in the local surface heat transfer coefficients on the same test specimen installed in different laboratories even though these laboratories measured identical surface heat transfer coefficients on their Calibration Transfer Standards. Inter-Laboratory Comparisons conducted by the NFRC have shown that the effect of this variation is reduced if the standardized thermal transmittance is used for comparison instead of the thermal transmittance. The standardized thermal transmittance is also a useful tool for the evaluation and comparison of experimental results of fenestration systems with computer calculations of the thermal transmittance. that are made because the current Historically, computer calculation methods (NFRC 100) for determining the thermal transmittance were not capable of applying the actual surface heat transfer coefficients that exist on the test specimen while testing at standardized conditions. These current computer calculation methods assumed that uniform standardized surface heat transfer coefficients exist on the indoor and outdoor fenestration product surfaces. Although the next generation of computer simulation programs includes improved radiation heat transfer algorithms, which generate non-uniform surface heat transfer coefficients, the standardized thermal transmittance remains to be a useful tool when comparing test results to computer modeling results. 4.6.1 It is important to recognize that due to radiation effects, the room side or weather side temperature (th and tc, respectively), has the potential to differ from the respective room side or weather side baffle temperatures (tb1 and tb2, respectively). If there is a difference of more than ±1 °C (±2 °F), either on the room side or weather side, the radiation effects shall be accounted for as described in Sections 6 and 9 to maintain accuracy in the calculated surface heat transfer coefficients. Calculating the radiation exchange for highly conductive test specimens or projecting fenestration products as described in Annex A2 is not a trivial task. 4.6.2 The calculation of the standardized thermal transmittance assumes that only the surface heat transfer coefficients change from the calibrated standardized values for the conditions of the test. This assumption is possibly not valid if the surface temperature differentials for the standardized calibration conditions are different from the surface temperature differential that exists on the test specimen during the test. Currently, specifications for the Calibration Transfer Standard give it a thermal transmittance of 1.7 W/(m2·K) [0.3 Btu/(hr·ft2·°F)]. Accordingly, the calculation of the standardized thermal transmittance produces the least error when performed on test specimens with a similar thermal transmittance. 4.6.3 It is important to note that the standardized surface heat transfer coefficients, hh and hc, as calibrated prior to testing a fenestration product using an appropriately sized Calibration Transfer Standard (CTS) have the potential to differ from the surface heat transfer coefficients that exist during a hot box test on a specific test specimen. Fenestration systems usually have frame and sash surfaces that introduce two- and three-dimensional convective heat transfer effects which result in variable surface heat transfer coefficients, which differ from the uniform standardized values. As a result of this, the test specimen surface heat transfer coefficients will differ from those obtained with the non-framed, essentially flat Calibration Transfer Standard tested under the same conditions. In this standardizing procedure, it is assumed that the differences are small enough so that the calibration surface heat transfer coefficients can be used to calculate equivalent test specimen average surfaces temperatures, t1 and t2, in order to estimate the actual test specimen surface heat transfer coefficients. It is important to recognize that this assumption will not be accurate for all fenestration products, especially for high thermal transmittance products where the surface heat transfer coefficients are a major portion of the overall thermal resistance and also for fenestration products with significant surface projections (for example, skylights, roof windows, garden windows) where the surface heat transfer coefficients are quite different from the standardized values. 4.6.4 In these situations, it is important to attempt to measure the test specimen surface temperature distributions and then calculate directly the test specimen average area weighted surfaces temperatures, t1 and t2. This area weighting (AW) method also has problems in that the placement of temperature sensors to get an accurate area weighting is not known, especially on high conductivity horizontal surfaces that act as heat transfer extended surfaces (that is, fins). In addition, the placement of many temperature sensors on the test specimen surfaces will affect the velocity fields in the vicinity of these surfaces which will affect the surface temperatures and surface heat transfer coefficients. 1.1 This test method covers requirements and guidelines and specifies calibration procedures required for the measurement of the steady-state thermal transmittance of fenestration systems installed vertically in the test chamber. This test method specifies the necessary measurements to be made using measurement systems conforming to Test Method C1363 for determination of fenestration system thermal transmittance. Note 1: This test method allows the testing of projecting fenestration products (that is, garden windows, skylights, and roof windows) installed vertically in a surround panel. Current research on skylights, roof windows, and projecting products hopefully will provide additional information that can be added to the next version of this test method so that skylight and roof windows can be tested horizontally or at some angle typical of a sloping roof. 1.2 This test method refers to the thermal transmittance, U of a fenestration system installed vertically in the absence of solar radiation and air leakage effects. Note 2: The methods described in this document may also be adapted for use in determining the thermal transmittance of sections of building wall, and roof and floor assemblies containing thermal anomalies, which are smaller than the hot box metering area. 1.3 This test method describes how to determine the thermal transmittance, US of a fenestration product (also called test specimen) at well-defined environmental conditions. The thermal transmittance is also a reported test result from Test Method C1363. If only the thermal transmittance is reported using this test method, the test report must also include a detailed description of the environmental conditions in the thermal chamber during the test as outlined in 10.1.14. 1.4 For rating purposes, this test method also describes how to calculate a standardized thermal transmittance, UST, which can be used to compare test results from laboratories with vastly different thermal chamber configurations, and facilitates the comparison to results from computer programs that use standard heat transfer coefficients to determine the thermal transmittance of fenestration products. Although this test method specifies two methods of calculating the standardized thermal transmittance, only the standardized thermal transmittance result from one method is reported for each test. One standardized thermal transmittance calculation procedure is the Calibration Transfer Standard (CTS) Method and another is the Area Weighting (AW) Method (see Section 9 for further descriptions of these two methods). The Area Weighting method requires that the surface temperatures on both sides of the test specimen be directly measured as specified in Practice E1423 in order to determine the surface heat transfer coefficients on the fenestration product during the test. The CTS Method does not use the measured surface temperatures on the test specimen and instead utilizes the calculation of equivalent surface temperatures from calibration data to determine the test specimen surface heat transfer coefficients. The AW shall be used whenever the thermal transmittance, US, is greater than 3.4 W/(m2·K) [0.6 Btu/(hr·ft 2·°F)], or when the ratio of test specimen projected surface area to wetted (that is, total heat transfer or developed) surface area on either side of the test specimen is less than 0.80. Otherwise the CTS Method shall be used to standardize the thermal transmittance results. 1.5 A discussion of the terminology and underlying assumptions for measuring the thermal transmittance are included. 1.6 The values stated in SI units are to be regarded as the standard. The values given in parentheses are provided for information purposes only. 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.

定价： 843元 / 折扣价： 717 元 加购物车

4.1 As determined by this test method, the pipe insulation lineal thermal resistance or conductance (and, when applicable, the thermal resistivity or conductivity) are means of comparing insulations which include the effects of the insulation and its fit upon the pipe, circumferential and longitudinal jointing, and variations in construction, but do not include the effects of the outer surface resistance or heat transfer coefficient. They are thus appropriate when the insulation outer-surface temperature and the pipe temperature are known or specified. However, since the thermal properties determined by this test method include the effects of fit and jointing, they are not true material properties. Therefore, properties determined by this test method are somewhat different from those obtained on apparently similar material in flat form using the guarded hot plate, Test Method C177, or the heat flow meter apparatus, Test Method C518.4.2 The pipe insulation lineal thermal transference incorporates both the effect of the insulation and its fit upon the pipe and also the effect of the surface heat-transfer coefficient. It is appropriate when the ambient conditions and the pipe temperature are known or specified and the thermal effects of the surface are to be included.4.3 Because of the test condition requirements prescribed in this test method, recognize that the thermal transfer properties obtained will not necessarily be the value pertaining under all service conditions. As an example, this test method provides that the thermal properties shall be obtained by tests on dry or conditioned specimens, while such conditions are not necessarily realized in service. The results obtained are strictly applicable only for the conditions of test and for the product construction tested, and must not be applied without proper adjustment when the material is used at other conditions, such as mean temperatures that differ appreciably from those of the test. With these qualifications in mind, the following apply:4.3.1 For horizontal or vertical pipes of the same size and temperature, operating in the same ambient environment, values obtained by this test method can be used for the direct comparison of several specimens, for comparison to specification values, and for engineering data for estimating heat loss of actual applications of specimens identical to those tested (including any jackets or surface treatments). When appropriate, correct for the effect of end joints and other recurring irregularities (4.4).4.3.2 When applying the results to insulation sizes different from those used in the test, an appropriate mathematical analysis is required. For homogeneous materials, this consists of the use of the thermal conductivity or resistivity values (corrected for any changes in mean temperature) plus the use of the surface heat transfer coefficient when the ambient temperature is considered (for example, see Practice C680). For nonhomogeneous and reflective insulation materials, a more detailed mathematical model is required which properly accounts for the individual modes of heat transfer (conduction, convection, radiation) and the variation of each mode with changing pipe size, insulation thickness, and temperature.4.4 It is difficult to measure the thermal performance of reflective insulation that incorporate air cavities, since the geometry and orientation of the air cavities can affect convective heat transfer. While it is always desirable to test full-length pipe sections, this is not always possible due to size limitations of existing pipe insulation testers. If insulation sections are tested less than full length, internal convective heat transfer are usually altered, which would affect the measured performance. Therefore, it must be recognized that the measured thermal performance of less than full-length insulation sections is not necessarily representative of full-length sections.4.5 The design of the guarded-end pipe apparatus is based upon negligible axial heat flow in the specimen, the test pipe, heaters, and other thermal conductive paths between the metering and guard sections. Some nonhomogeneous and reflective insulation are usually modified at the end over the guard gap in order to prevent axial heat flow. Avoid these modifications where possible, but for some nonhomogeneous insulation designs, they provide the only means to satisfy the negligible heat flow assumption across the guard gaps. Therefore, thermal performance measured on insulation specimens with modified ends are not necessarily representative of the performance of standard insulation sections.4.6 It is acceptable to use this test method to determine the effect of end joints or other isolated irregularities by comparing tests of two specimens, one of which is uniform throughout its length and the other which contains the joint or other irregularity within the test section. The difference in heat loss between these two tests, corrected for the uniform area covered by the joint or other irregularity, is the extra heat loss introduced. Care must be taken that the tests are performed under the same conditions of pipe and ambient temperature and that sufficient length exists between the joint or irregularity and the test section ends to prevent appreciable end loss.4.7 For satisfactory results in conformance with this test method, the principles governing construction and use of apparatus described in this test method must be followed. If the results are to be reported as having been obtained by this test method, then all the pertinent requirements prescribed in this test method shall be met or any exceptions shall be described in the report.4.8 It is not practical in a test method of this type to establish details of construction and procedure to cover all contingencies that might offer difficulties to a person without technical knowledge concerning the theory of heat flow, temperature measurements, and general testing practices. Standardization of this test method does not reduce the need for such technical knowledge. It is recognized also that it would be unwise to restrict the further development of improved or new methods or procedures by research workers because of standardization of this test method.FIG. 1 Guarded-End ApparatusNOTE 4: When testing at ambient temperatures below normal room temperatures, theoretical analysis shows that the experimental heat flow direction is unimportant for a perfectly homogenous material. However, if the properties of the insulation vary in the radical direction, the experimental heat flow direction will significantly affect the measured thermal conductivity. Exercise great care when using data from a radial heat flow outward experiment for a radial heat flow inward application.1.1 This test method covers the measurement of the steady-state heat transfer properties of pipe insulations. Specimen types include rigid, flexible, and loose fill; homogeneous and nonhomogeneous; isotropic and nonisotropic; circular or non-circular cross section. Measurement of metallic reflective insulation and mass insulations with metal jackets or other elements of high axial conductance is included; however, additional precautions must be taken and specified special procedures must be followed.1.2 The test apparatus for this purpose is a guarded-end or calibrated-end pipe apparatus. The guarded-end apparatus is a primary (or absolute) method. The guarded-end method is comparable, but not identical to ISO 8497. The ISO method does not use the calculation procedure in Practice C1045.1.3 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 When appropriate, or as required by specifications or other test methods, the following thermal transfer properties for the specimen can be calculated from the measured data (see 3.2):1.4.1 The pipe insulation lineal thermal resistance and conductance,1.4.2 The pipe insulation lineal thermal transference,1.4.3 The surface areal resistance and heat transfer coefficient,1.4.4 The thermal resistivity and conductivity,1.4.5 The areal thermal resistance and conductance, and1.4.6 The areal thermal transference.NOTE 1: In this test method the preferred resistance, conductance, and transference are the lineal values computed for a unit length of pipe. These must not be confused with the corresponding areal properties computed on a unit area basis which are more applicable to flat slab geometry. If these areal properties are computed, the area used in their computation must be reported.NOTE 2: Discussions of the appropriateness of these properties to particular specimens or materials may be found in Test Method C177, Test Method C518, and in the literature (1).21.5 This test method allows for operation over a wide range of temperatures. The upper and lower limit of the pipe surface temperature is determined by the maximum and minimum service temperature of the specimen or of the materials used in constructing the apparatus. In any case, the apparatus must be operated such that the temperature difference between the exposed surface and the ambient is sufficiently large enough to provide the precision of measurement desired. Normally the apparatus is operated in closely controlled still air ambient from 15 to 30°C, but other temperatures, other gases, and other velocities are acceptable. It is also acceptable to control the outer specimen surface temperature by the use of a heated or cooled outer sheath or blanket or by the use of an additional uniform layer of insulation.1.6 The use any size or shape of test pipe is allowable provided that it matches the specimens to be tested. Normally the test method is used with circular pipes; however, its use is permitted with pipes or ducts of noncircular cross section (square, rectangular, hexagonal, etc.). One common size used for interlaboratory comparison is a pipe with a circular cross section of 88.9-mm diameter (standard nominal 80-mm [3-in.] pipe size), although several other sizes are reported in the literature (2-4).1.7 The test method applies only to test pipes with a horizontal or vertical axis. For the horizontal axis, the literature includes using the guarded-end, the calibrated, and the calibrated-end cap methods. For the vertical axis, no experience has been found to support the use of the calibrated or calibrated-end methods. Therefore the method is restricted to using the guarded-end pipe apparatus for vertical axis measurements.1.8 This test method covers two distinctly different types of pipe apparatus, the guarded-end and the calibrated or calculated-end types, which differ in the treatment of axial heat transfer at the end of the test section.1.8.1 The guarded-end apparatus utilizes separately heated guard sections at each end, which are controlled at the same temperature as the test section to limit axial heat transfer. This type of apparatus is preferred for all types of specimens within the scope of this test method and must be used for specimens incorporating elements of high axial conductance.1.8.2 The calibrated or calculated-end apparatus utilizes insulated end caps at each end of the test section to minimize axial heat transfer. Corrections based either on the calibration of the end caps under the conditions of test or on calculations using known material properties, are applied to the measured test section heat transfer. These apparatuses are not applicable for tests on specimens with elements of high axial conductance such as reflective insulations or metallic jackets. There is no known experience on using these apparatuses for measurements using a vertical axis.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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.10 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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1.1 This test method, known as the guarded hot box method, covers the measurement of the steady-state thermal transfer properties of panels. In distinction to Test Method C177, which is primarily applicable to homogeneous samples, the guarded hot box method provides for the evaluation of thermal performance of building assemblies. This test method is suitable for building construction assemblies, building panels, and other applications of nono-homogeneous specimens at similar temperature ranges. It may also be used for homogeneous specimens. 1.2 This test method may be applied to any building construction for which it is possible to build a reasonably representative specimen of size appropriate for the apparatus. Note 1-A calibrated hot box, Test Method C976, may also be used for the described measurements and may prove more satisfactory for testing assemblies under dynamic conditions (nonsteady-state) and to evaluate the effects of water migration and air infiltration. The choice between the calibrated or the guarded hot box should be made only after careful consideration of the contemplated use. 1.3 In applying this test method, the general principles outlined must be followed; however, the details of the apparatus and procedures may be varied as needed. 1.3.1 The intent of this test method is to give the essential principles and the general arrangement of the apparatus. Any test using this apparatus must follow those principles. The details of the apparatus and the suggested procedures that follow are given not as mandatory requirements but as examples of this test method and precautions that have been found useful to satisfy the essential principles. 1.3.2 Persons applying this test method shall be trained in the methods of temperature measurement, shall possess a knowledge of the theory of heat flow, and shall understand the general requirements of testing practice. 1.3.3 This standard does not purport to address all of the safety problems, 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. Note 2-While various units may be found for thermal properties, the International System of units is used exclusively in this test method. For conversion factors to inch-pound and kilogram-calorie systems, see Table 1.

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5.1 This test method covers the measurement of heat flux and associated test conditions for flat specimens. The guarded-hot-plate apparatus is generally used to measure steady-state heat flux through materials having a “low” thermal conductivity and commonly denoted as “thermal insulators.” Acceptable measurement accuracy requires a specimen geometry with a large ratio of area to thickness.5.2 Two specimens are selected with their thickness, areas, and densities as identical as possible, and one specimen is placed on each side of the guarded-hot-plate. The faces of the specimens opposite the guarded-hot-plate and primary guard are placed in contact with the surfaces of the cold surface assemblies.5.3 Steady-state heat transmission through thermal insulators is not easily measured, even at room temperature. This is due to the fact heat transmission through a specimen occurs by any or all of three separate modes of heat transfer (radiation, conduction, and convection). It is possible that any inhomogeneity or anisotropy in the specimen will require special experimental precautions to measure that flow of heat. In some cases it is possible that hours or even days will be required to achieve the thermal steady-state. No guarding system can be constructed to force the metered heat to pass only through the test area of insulation specimen being measured. It is possible that moisture content within the material will cause transient behavior. It is also possible that and physical or chemical change in the material with time or environmental condition will permanently alter the specimen.5.4 Application of this test method on different test insulations requires that the designer make choices in the design selection of materials of construction and measurement and control systems. Thus it is possible that there will be different designs for the guarded-hot-plate apparatus when used at ambient versus cryogenic or high temperatures. Test thickness, temperature range, temperature difference range, ambient conditions and other system parameters must also be selected during the design phase. Annex A1 is referenced to the user, which addresses such issues as limitations of the apparatus, thickness measurement considerations and measurement uncertainties, all of which must be considered in the design and operation of the apparatus.5.5 Apparatus constructed and operated in accordance with this test method should be capable of accurate measurements for its design range of application. Since this test method is applicable to a wide range of specimen characteristics, test conditions, and apparatus design, it is impractical to give an all-inclusive statement of precision and bias for the test method. Analysis of the specific apparatus used is required to specify a precision and bias for the reported results. For this reason, conformance with the test method requires that the user must estimate and report the uncertainty of the results under the reported test conditions.5.6 Qualification of a new apparatus. When a new or modified design is developed, tests shall be conducted on at least two materials of known thermal stability and having verified or calibrated properties traceable to a national standards laboratory. Tests shall be conducted for at least two sets of temperature conditions that cover the operating range for the apparatus. If the differences between the test results and the national standards laboratory characterization are determined to be significant, then the source of the error shall, if possible, be identified. Only after successful comparison with the certified samples, can the apparatus claim conformance with this test method. It is recommended that checks be continued on a periodic basis to confirm continued conformance of the apparatus.5.7 The thermal transmission properties of a specimen of material have the potential to be affected due to the following factors: (a) composition of the material (b) moisture or other environmental conditions (c) time or temperature exposure (d) thickness (e) temperature difference across the specimen (f) mean temperature. It must be recognized, therefore, that the selection of a representative value of thermal transmission properties for a material must be based upon a consideration of these factors and an adequate amount of test information.5.8 Since both heat flux and its uncertainty may be dependent upon environmental and apparatus test conditions, as well as intrinsic characteristics of the specimen, the report for this test method shall include a thorough description of the specimen and of the test conditions.5.9 The results of comparative test methods such as Test Method C518 depend on the quality of the heat flux reference standards. The apparatus in this test method is one of the absolute methods used for generation of the reference standards. The accuracy of any comparative method can be no better than that of the referenced procedure. While it is possible that the precision of a comparative method such as Test Method C518 will be comparable with that of this test method, Test Method C518 cannot be more accurate. In cases of dispute, this test method is the recommended procedure.1.1 This test method establishes the criteria for the laboratory measurement of the steady-state heat flux through flat, homogeneous specimen(s) when their surfaces are in contact with solid, parallel boundaries held at constant temperatures using the guarded-hot-plate apparatus.1.2 The test apparatus designed for this purpose is known as a guarded-hot-plate apparatus and is a primary (or absolute) method. This test method is comparable, but not identical, to ISO 8302.1.3 This test method sets forth the general design requirements necessary to construct and operate a satisfactory guarded-hot-plate apparatus. It covers a wide variety of apparatus constructions, test conditions, and operating conditions. Detailed designs conforming to this test method are not given but must be developed within the constraints of the general requirements. Examples of analysis tools, concepts and procedures used in the design, construction, calibration and operation of a guarded-hot-plate apparatus are given in Refs (1-41).21.4 This test method encompasses both the single-sided and the double-sided modes of measurement. Both distributed and line source guarded heating plate designs are permitted. The user should consult the standard practices on the single-sided mode of operation, Practice C1044, and on the line source apparatus, Practice C1043, for further details on these heater designs.1.5 The guarded-hot-plate apparatus can be operated with either vertical or horizontal heat flow. The user is cautioned however, since the test results from the two orientations may be different if convective heat flow occurs within the specimens.1.6 Although no definitive upper limit can be given for the magnitude of specimen conductance that is measurable on a guarded-hot-plate, for practical reasons the specimen conductance should be less than 16 W/(m2K).1.7 This test method is applicable to the measurement of a wide variety of specimens, ranging from opaque solids to porous or transparent materials, and a wide range of environmental conditions including measurements conducted at extremes of temperature and with various gases and pressures.1.8 Inhomogeneities normal to the heat flux direction, such as layered structures, can be successfully evaluated using this test method. However, testing specimens with inhomogeneities in the heat flux direction, such as an insulation system with thermal bridges, can yield results that are location specific and shall not be attempted with this type of apparatus. See Test Method C1363 for guidance in testing these systems.1.9 Calculations of thermal transmission properties based upon measurements using this method shall be performed in conformance with Practice C1045.1.10 In order to ensure the level of precision and accuracy expected, persons applying this standard must possess a knowledge of the requirements of thermal measurements and testing practice and of the practical application of heat transfer theory relating to thermal insulation materials and systems. Detailed operating procedures, including design schematics and electrical drawings, should be available for each apparatus to ensure that tests are in accordance with this test method. In addition, automated data collecting and handling systems connected to the apparatus must be verified as to their accuracy. This can be done by calibration and inputting data sets, which have known results associated with them, into computer programs.1.11 It is not practical for a test method of this type to establish details of design and construction and the procedures to cover all contingencies that might offer difficulties to a person without technical knowledge concerning theory of heat flow, temperature measurements and general testing practices. The user may also find it necessary, when repairing or modifying the apparatus, to become a designer or builder, or both, on whom the demands for fundamental understanding and careful experimental technique are even greater. Standardization of this test method is not intended to restrict in any way the future development of new or improved apparatus or procedures.1.12 This test method does not specify all details necessary for the operation of the apparatus. Decisions on sampling, specimen selection, preconditioning, specimen mounting and positioning, the choice of test conditions, and the evaluation of test data shall follow applicable ASTM Test Methods, Guides, Practices or Product Specifications or governmental regulations. If no applicable standard exists, sound engineering judgment that reflects accepted heat transfer principles must be used and documented.1.13 This test method allows a wide range of apparatus design and design accuracy to be used in order to satisfy the requirements of specific measurement problems. Compliance with this test method requires a statement of the uncertainty of each reported variable in the report. A discussion of the significant error factors involved is included.1.14 Major sections within this test method are arranged as follows:Section Section 1Referenced Documents 2Terminology 3Summary of Test Method 4 5Apparatus 6Specimen Preparation and Conditioning 7Procedure 8Calculation of Results 9Report 10Precision and Bias 11Keywords 12Figures  General Arrangement of the Mechanical Components of the Guarded-Hot-Plate Apparatus Fig. 1Illustration of Heat Flow in the Guarded-Hot-Plate Apparatus Fig.2Example Report Form Fig. 3Annexes  Importance of Thickness A1.1Measuring Thickness A1.2Limitations Due to Apparatus A1.3Limitations Due to Temperature A1.4Limitations Due to Specimen A1.5Random and Systematic Error Components A1.6Error Components for Variables A1.7Thermal Conductance or Thermal Resistance Error Analysis A1.8Thermal Conductivity or Thermal Resistivity Error Analysis A1.9Uncertainty Verification A1.101.15 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.16 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 Note 22.1.17 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 ASTM thermal test method descriptions are complex because of added apparatus details necessary to ensure accurate results. As a result, many users find it difficult to locate the data reduction details necessary to reduce the data obtained from these tests. This practice is designed to be referenced in the thermal test methods, thus allowing those test methods to concentrate on experimental details rather than data reduction.4.2 This practice is intended to provide the user with a uniform procedure for calculating the thermal transmission properties of a material or system from standard test methods used to determine heat flux and surface temperatures. This practice is intended to eliminate the need for similar calculation sections in the ASTM Test Methods (C177, C335, C518, C1033, C1114, C1199, and C1363) by permitting use of these standard calculation forms by reference.4.3 This practice provides the method for developing the thermal conductivity as a function of temperature for a specimen from data taken at small or large temperature differences. This relationship can be used to characterize material for comparison to material specifications and for use in calculations programs such as Practice C680.4.4 Two general solutions to the problem of establishing thermal transmission properties for application to end-use conditions are outlined in Practice C1058. (Practice C1058 should be reviewed prior to use of this practice.) One is to measure each product at each end-use condition. This solution is rather straightforward, but burdensome, and needs no other elaboration. The second is to measure each product over the entire temperature range of application conditions and to use these data to establish the thermal transmission property dependencies at the various end-use conditions. One advantage of the second approach is that once these dependencies have been established, they serve as the basis for estimating the performance for a given product at other conditions. Warning— The use of a thermal conductivity curve developed in Section 6 must be limited to a temperature range that does not extend beyond the range of highest and lowest test surface temperatures in the test data set used to generate the curve.1.1 This practice provides the user with a uniform procedure for calculating the thermal transmission properties of a material or system from data generated by steady state, one dimensional test methods used to determine heat flux and surface temperatures. This practice is intended to eliminate the need for similar calculation sections in Test Methods C177, C335, C518, C1033, C1114 and C1363 and Practices C1043 and C1044 by permitting use of these standard calculation forms by reference.1.2 The thermal transmission properties described include: thermal conductance, thermal resistance, apparent thermal conductivity, apparent thermal resistivity, surface conductance, surface resistance, and overall thermal resistance or transmittance.1.3 This practice provides the method for developing the apparent thermal conductivity as a function of temperature relationship for a specimen from data generated by standard test methods at small or large temperature differences. This relationship can be used to characterize material for comparison to material specifications and for use in calculation programs such as Practice C680.1.4 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 practice includes a discussion of the definitions and underlying assumptions for the calculation of thermal transmission properties. Tests to detect deviations from these assumptions are described. This practice also considers the complicating effects of uncertainties due to the measurement processes and material variability. See Section 7.1.6 This practice is not intended to cover all possible aspects of thermal properties data base development. For new materials, the user should investigate the variations in thermal properties seen in similar materials. The information contained in Section 7, the Appendix and the technical papers listed in the References section of this practice may be helpful in determining whether the material under study has thermal properties that can be described by equations using this practice. Some examples where this method has limited application include: (1) the onset of convection in insulation as described in Reference (1); (2) while a phase change is taking place in one of the insulation components causing an unsteady-state condition; and (3) the influence of heat flow direction and temperature difference changes for reflective insulations.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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1.1 This test method covers the measurement of the steady-state heat transfer properties of pipe insulations for pipes operating at temperatures above the ambient environment from approximately 40oC to the maximum insulation design temperature. Specimens may be rigid, flexible, or loose-fill, may be homogeneous or nonhomogeneous, isotropic or nonisotropic, and of circular or noncircular cross section. Measurement of metallic reflective insulations is included in this test method; however, additional precautions must be taken when these materials are being evaluated.1.2 When appropriate, or as required by specifications or other test methods, the following thermal transfer properties for the specimen can be calculated from the measured data (see 3.2 ):1.2.1 The thermal resistance and conductance,1.2.2 The thermal transference,1.2.3 The surface resistance and heat transfer coefficient, and1.2.4 The apparent thermal resistivity and conductivity.1.3 This test method applies only for testing of insulations on vertical pipes, and the results will only apply for insulations installed vertically (see Note 1).1.4 The test pipe may be of any size or shape provided that it matches the specimens to be tested. Normally the test method is used with circular pipes, however, its use is permitted with pipes or ducts of noncircular cross section (square, rectangular, hexagonal, etc.). One common size used for interlaboratory comparison is a pipe with an 88.9-mm outside diameter (standard nominal 80-mm, 3-in. pipe size).1.5 This test method covers only the guarded-end type of pipe apparatus. No experience has been gathered with the calibrated or calculated-end pipe apparatus; therefore, this type of tester is not included as part of this specification.1.6 The values stated in SI units are to be regarded as the standard. Conversion factors to other units are given in . The units used must accompany all numerical values.Note 1--Measurement of insulations installed horizontally is covered in Test Method C335 and Test Method C691.Note 2--Discussions of the appropriateness of these properties to particular specimens or materials may be found in Test Method C177,Test Method C518, and in the literature.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 and health practices and determine the applicability of regulatory limitations prior to use.

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5.1 PN Junction Diode—The steady-state photocurrent of a simple p-n junction diode is a directly measurable quantity that can be directly related to device response over a wide range of ionizing radiation. For more complex devices the junction photocurrent may not be directly related to device response.5.2 Zener Diode—In this device, the effect of the photocurrent on the Zener voltage rather than the photocurrent itself is usually most important. The device is most appropriately tested while biased in the Zener region. In testing Zener diodes or precision voltage regulators, extra precaution must be taken to make certain the photocurrent generated in the device during irradiations does not cause the voltage across the device to change during the test.5.3 Bipolar Transistor—As device geometries dictate that photocurrent from the base-collector junction be much greater than current from the base-emitter junction, measurements are usually made only on the collector-base junction with emitter open; however, sometimes, to obtain data for computer-aided circuit analysis, the emitter-base junction photocurrent is also measured.5.4 Junction Field-Effect Device—A proper photocurrent measurement requires that the source be shorted (dc) to the drain during measurement of the gate-channel photocurrent. In tetrode-connected devices, the two gate-channel junctions should be monitored separately.5.5 Insulated Gate Field-Effect Device—In this type of device, the true photocurrent is between the substrate and the channel, source, and drain regions. A current which can generate voltage that will turn on the device may be measured by the technique used here, but it is due to induced conductivity in the gate insulator and thus is not a junction photocurrent.1.1 This test method covers the measurement of steady-state primary photocurrent, Ipp, generated in semiconductor devices when these devices are exposed to ionizing radiation. These procedures are intended for the measurement of photocurrents greater than 10−9 A·s/Gy(Si or Ge), in cases for which the relaxation time of the device being measured is less than 25 % of the pulse width of the ionizing source. The validity of these procedures for ionizing dose rates as great as 108Gy(Si or Ge)/s has been established. The procedures may be used for measurements at dose rates as great as 1010Gy(Si or Ge)/s; however, extra care must be taken. Above 108Gy/s, the package response may dominate the device response for any device. Additional precautions are also required when measuring photocurrents of 10−9 A·s/Gy(Si or Ge) or lower.1.2 Setup, calibration, and test circuit evaluation procedures are also included in this test method.1.3 Because of the variability between device types and in the requirements of different applications, the dose rate range over which any specific test is to be conducted is not given in this test method but must be specified separately.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.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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