1.1 This test method covers determination of the compatibility of commercial SCA and commercial ethylene and propylene glycol engine coolant concentrates. This test method focuses on the solubility of specific chemical species formed in the engine coolant. The short duration of the test (24 h), among other restrictions, makes the test method of limited use for sorting out a variety of chemical compatibility problems in which a component of the SCA may react with a component of the coolant additive package. The test as currently written also does not deal with the issue of hard water compatibility, in which a component of the coolant or SCA additive package reacts with the hardness (Ca and Mg) to form a precipitate. 1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound units that are provided for information only and are not considered 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. 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.