1.1 This test method determines the change in length on drying of mortar bars containing hydraulic cement and graded standard sand. 1.2 The values stated in SI units are to be regarded as standard. When combined standards are referenced, the selection of measurement system is at the user's discretion subject to the requirements of the referenced standard. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Warning-Fresh hydraulic cementitious mixtures are caustic and may cause chemical burns to skin and tissue upon prolonged exposure).2 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.