This test method covers the determination of water with true concentration range from 0.02 % to 5.00 % by mass or volume in crude oils using Procedures A and B and from 0.04 % to 3.75 % by mass or volume for Procedure C. Mercaptan (RSH) and sulfide (S− or H2S) as sulfur are known to interfere with this test method, but at levels of less than 500 μg ⁄g [ppm(m)], the interference from these compounds is insignificant (see Section 6).
This test method is intended for use with standard commercially available coulometric Karl Fischer reagent.