ASTM C 471M:2025

1.1 These test methods cover the chemical analysis of gypsum and gypsum panel products, including gypsum ready-mixed plaster, gypsum wood-fibered plaster, and gypsum concrete. 1.2 These test methods appear in the following order: Sections Preparation of Sample 4 Complete Procedure 5 - 16 Alternative Procedure for Analysis of Free Water in 17 Gypsum Using a Moisture Balance Alternative Procedure for Analysis of Combined Water in 18 Gypsum Using a Moisture Balance Alternative Procedure for Analysis of Organic Material 20 and Carbon Dioxide in Gypsum by High Temperature Weight Loss Alternative Procedure for Analysis for Calcium Sulfate by 21 Ammonium Acetate Method Alternative Procedure for Analysis for Sodium Chloride by 22 the Coulometric Method Determination of Sand in Set Plaster 23 Wood-fiber Content in Wood-fiber Gypsum Plaster 24 Optional Procedure for Analysis for Sodium by the Atomic 25 Absorption Method Optional Procedure for Analysis for Sodium by Flame 26 Photometry Determination of Orthorhombic Cyclooctasulfur (S 8 ) in 27 Ggypsum Panel Products-General Provisions Determination of Orthorhombic Cyclooctasulfur (S 8 ) in 28 Gypsum Panel Products by Gas Chromatograph Equipped with a Mass Spectrometer (GS/MS) Determination of Orthorhombic Cyclooctasulfur (S 8 ) in 29 Gypsum Panel Products by Gas Chromatograph Equipped with an Electron Capture Detector (GC/ECD) Determination of Orthorhombic Cyclooctasulfur (S 8 ) in 30 Gypsum Panel Products by High-performance Liquid Chromatograph Equipped with and Ultraviolet Detector (HPLC/UV) 1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in these test methods. 1.4 These text of this test method references notes and footnotes that provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the 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.

91.100.10