4.1 This test method permits the determination of very low levels of chloride ion in engine coolants containing the common corrosion inhibitor, mercaptobenzothiazole, or related mercaptans, which would normally interfere with the titration by also forming insoluble silver salts with silver nitrate.

1.1 This test method covers the determination of chloride ion in engine coolants in the range from 5 ppm to 200 ppm in the presence of up to 0.6 weight % mercaptobenzothiazole.

1.2 Other materials that react with silver ion will interfere.

1.3 Chloride in engine coolants containing an aryltriazole instead of mercaptobenzothiazole can be determined directly by this test method without pretreatment with hydrogen peroxide.

1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this 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. Specific hazards statements are given in Section 7.

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.