This test method covers the determination of the air content of hydraulic cement mortar under the conditions hereinafter specified. The values stated in SI units are to be regarded as the standard. Values in SI shall be obtained by measurement in SI units or by appropriate conversion@ using the Rules for Conversion and Rounding in IEEE/ASTM SI 10@ of measurements made in other units. 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. Warning - Fresh hydraulic cementitious mixtures are caustic and may cause chemical burns to skin and tissue upon prolonged exposure.