在双硫腙作为指示剂的情况下，用标准体积的硝酸铅（II）溶液滴定供试品的缓冲丙酮溶液。本方法适用于含有硫酸钠、硫酸铵和硫酸烷醇胺的阴离子表面活性剂。它不适用于含有磷酸盐或大量氯化物等其他化合物的产品，也不适用于含有大量弱酸盐（例如，肥皂或磺基琥珀酸单酯）的产品。

A buffered acetonic solution of a test portion is titrated with a standard volumetric lead(II) nitrate solution in the presence of dithizone as indicator. The method is applicable to anionic surface active agents, containing sodium, ammonium and alkanolamine sulphates. It is not applicable to products containing other compounds such as phosphates or large amounts of chloride nor is it applicable in the presence of large amounts of salts of weak acids (for example, soaps or monoesters of sulphosuccinic acid).