This standard describes liquid sodium silicate used in the preparation of activated silica, which is used as a coagulant aid for the treatment of potable water, wastewater, or reclaimed water and for (1) the control of corrosion and (2) stabilization of iron and manganese. It can be referenced in documents for purchasing and receiving liquid sodium silicate and can be used as a guide for testing the physical and chemical properties of liquid sodium silicate samples. The stipulations of this standard apply when this document has been referenced and then only to liquid sodium silicate used in potable water, wastewater, or reclaimed water.