【国外标准】 Standard Test Method for Acidity in Volatile Solvents and Chemical Intermediates Used in Paint, Varnish, Lacquer, and Related Products

4.1 This test method is useful for determining low levels of acidity, below 0.05 %, in organic compounds and hydrocarbon mixtures. The total acidity is calculated as acetic acid or milligrams of sodium hydroxide per gram of sample.4.2 Acidity may be present as a result of contamination, decomposition during storage or distribution, or manufacture. This test method may be used in assessing compliance with a specification.1.1 This test method covers the determination of total acidity as acetic acid, in concentrations below 0.05 %, in organic compounds and hydrocarbon mixtures used in paint, varnish, and lacquer solvents and diluents. It is known to be applicable to such mixtures as low molecular weight saturated and unsaturated alcohols, ketones, ethers, esters, hydrocarbon diluents, naphtha, and other light distillate petroleum fractions.1.2 For purposes of determining conformance of an observed value or a calculated value using this test method to relevant specifications, test result(s) shall be rounded off “to the nearest unit” in the last right-hand digit used in expressing the specification limit, in accordance with the rounding-off method of Practice E29.1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.4 For specific hazard information and guidance consult supplier’s Safety Data Sheet.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.