本文件适用于用于治疗人类消费用水的四氢双（正磷酸）钙。它描述了特征，并规定了四氢双（正磷酸）钙的要求和相应的测试方法。它提供了关于其在水处理中的用途的信息

This document is applicable to calcium tetrahydrogen bis(orthophosphate) used for treatment of water intended for human consumption. It describes the characteristics and specifies the requirements and the corresponding tests methods for calcium tetrahydrogen bis(orthophosphate). It gives information on its use in water treatment.