The calculated cost of property loss and destruction in combination with the cost of overages presents a logical foundation for the development of alternative models which can be used to evaluate the effectiveness of property management systems and provide relevant information to management useful for the distribution of resources to the task of property utilization and control.The understanding of an organization’loss, destruction and overage cost of inventory is a necessary prerequisite to the development of cost effective systems for the management of movable, durable assets.The costing model used in this standard assumes that individual categories of property represent a range of realized costs to an organization and that these loss or destruction costs can range from significant to minimal.The use of overage is a necessary corollary to the model since there can be significant costs associated with the inventory and control of unneeded assets.1.1 This practice covers the assignment of a value to categories and complete populations of lost or destroyed property assets for the purpose of determining the composite cost of all such losses on a periodic basis. This practice does not address the valuation of individual property assets.1.2 The reason for assigning a loss or destruction value is to establish an economic basis for the allocation of resources to manage property efficiently and in a cost effective manner.1.3 The direct cost of lost, damaged or destroyed (LDD) property has little to do with the acquisition, book or market value of such assets. While in many organizations, the value of LDD property is reflected at acquisition cost in the General Ledger accounts this approach is only appropriate for the financial reporting of property assets.1.4 The calculation of the cost of loss or destruction of property for the purposes of computing a necessary factor to be used in the equation applied under Practice E 2219 is to be based upon the consideration of both the risk of an inventory shortage as well as the benefits of inventory control and overage management.1.5 The valuation of property for the purposes of management and control is to be based upon the consideration of both the risk of an inventory shortage and benefits of inventory management as contained in this standard.

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5.1 Manufacturers of radiant barriers express the performance of their products in terms of the total hemispherical emittance. The purpose of a radiant barrier is to decrease the radiation heat transfer across the attic air space, and hence, to decrease the heat loss or gain through the ceiling below the attic. The amount of decrease in heat flow will depend upon a number of factors, such as weather conditions, amount of mass or reflective insulation in the attic, solar absorptance of the roof, geometry of the attic and roof, and amount and type of attic ventilation. Because of the infinite combinations of these factors, it is not practical to publish data for each possible case.5.2 The calculation of heat loss or gain of a system containing radiant barriers is mathematically complex, and because of the iterative nature of the method, it is best handled by computers.5.3 Computers are now widely available to most producers and consumers of radiant barriers to permit the use of this practice.5.4 The user of this practice may wish to modify the data input to represent accurately the structure. The computer program also may be modified to meet individual needs. Also, additional calculations may be desired, for example, to sum the hourly heat flows in some fashion to obtain estimates of seasonal or annual energy usages. This might be done using the hourly data as inputs to a whole-house model, and by choosing house balance points to use as cutoff points in the summations.1.1 This practice covers the estimation of heat gain or loss through ceilings under attics containing radiant barriers by use of a computer program. The computer program included as an adjunct to this practice provides a calculational procedure for estimating the heat loss or gain through the ceiling under an attic containing a truss or rafter mounted radiant barrier. The program also is applicable to the estimation of heat loss or gain through ceilings under an attic without a radiant barrier. This procedure utilizes hour-by-hour weather data to estimate the hour-by-hour ceiling heat flows. The interior of the house below the ceiling is assumed to be maintained at a constant temperature. At present, the procedure is applicable to sloped-roof attics with rectangular floor plans having an unshaded gabled roof and a horizontal ceiling. It is not applicable to structures with flat roofs, vaulted ceilings, or cathedral ceilings. The calculational accuracy also is limited by the quality of physical property data for the construction materials, principally the insulation and the radiant barrier, and by the quality of the weather data.1.2 Under some circumstances, interactions between radiant barriers and HVAC ducts in attics can have a significant effect on the thermal performance of a building. Ducts are included in an extension of the computer model given in the appendix.1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 This test method provides a quantitative measure of the susceptibility to intergranular corrosion of Al-Mg and Al-Mg-Mn alloys. The nitric acid dissolves a second phase, an aluminum-magnesium intermetallic compound (βAl-Mg), in preference to the solid solution of magnesium in the aluminum matrix. When this compound is precipitated in a relatively continuous network along grain boundaries, the effect of the preferential attack is to corrode around the grains, causing them to fall away from the specimens. Such dropping out of the grains causes relatively large mass losses of the order of 25 mg/cm2 to 75 mg/cm2 (160 mg/in.2 to 480 mg/in.2), whereas, samples of intergranular-resistant materials lose only about 1 mg/cm2 to 15 mg/cm2 (10 mg/in.2 to 100 mg/in.2). When the βAl-Mg compound is randomly distributed, the preferential attack can result in intermediate mass losses. Metallographic examination is required in such cases to establish whether or not the loss in mass is the result of intergranular attack.4.2 The precipitation of the second phase in the grain boundaries also gives rise to intergranular corrosion when the material is exposed to chloride-containing natural environments, such as seacoast atmospheres or sea water. The extent to which the alloy will be susceptible to intergranular corrosion depends upon the degree of precipitate continuity in the grain boundaries. Visible manifestations of the attack may be in various forms such as pitting, exfoliation, or stress-corrosion cracking, depending upon the morphology of the grain structure and the presence of sustained tensile stress.31.1 This test method, also known as the Nitric Acid Mass Loss Test (NAMLT), covers a procedure for constant immersion intergranular corrosion testing of 5XXX series aluminum alloys.1.2 This test method is applicable only to wrought products.1.3 This test method covers type of specimen, specimen preparation, test environment, and method of exposure.1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, 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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