ASTM D4458-15

5.1 Chloride is present in virtually all oil field brines, seawaters, and many waste waters. Identification of the origin of the water and selection of its disposal method may be based upon the chloride content. The chloride content is also used to estimate the resistivity of formation waters and to differentiate between subsurface formations.

1.1 This test method2 is applicable to the measurement of chloride in highly mineralized waters such as oil field brines, seawater, and brackish water. The test method is based upon the titration of chloride with silver nitrate, using a visual indicator.

1.2 Samples containing from 10 to 150 mg of chloride can be analyzed by this test method. These levels are achieved by dilution as described in the test method.

1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.4 It is the user's responsibility to assure the validity of the method for untested types of water.

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 and health practices and determine the applicability of regulatory limitations prior to use.