【国外标准】 Standard Practice for Sampling Nonferrous Metals and Alloys in Cast Form for Determination of Chemical Composition

This specification covers the requirements for Halon 1301, or halogenated hydrocarbon compound Bromotrifluoromethane (CF3Br) as a fire-fighting medium. The fire-fighting equipment or hardware that employs Halon 1301, the conditions of employing such equipment (for example, handhelds, fixed installations, etc.), and the storage or transportation of Halon 1301, are not addressed in this specification. The material shall be tested for purity, methanol impurity, acidity, water content, halogen ion content, nonvolatile residue, suspended matter and sediment, and fixed or nonabsorbable gases in the vapor phase.1.1 This practice covers the sampling, for the determination of chemical composition (Note 1) of nonferrous metals and alloys, excluding aluminum, in cast form for remelting or mechanical working.1.1.1 Refer to Practice E255 for copper and copper alloys.NOTE 1: The selection of correct portions of material and the preparation of a representative sample from such portions are necessary prerequisites to every analysis, the analysis being of no value unless the sample actually represents the average composition of the material from which it was selected.1.2 When agreed upon between the purchaser and the manufacturer, the heat sample and analysis may be accepted as representative of the composition of the metal. In such cases, each lot must be properly identified with the heats from which it was made.1.3 This practice is intended to cover the general principles of sampling applicable to nonferrous metals in cast form and is not intended to supersede or replace existing specification requirements for sampling of a particular material.1.4 The values stated in SI units are to be regarded as 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 and health 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.