This standard describes monosodium phosphate, anhydrous and liquid, for use in the treatment of potable water, wastewater, and reclaimed water. The product described is an orthophosphate used as formulated and in blends to inhibit corrosion of water conveyance systems. The product described by this standard is also known as sodium phosphate, monobasic, anhydrous and liquid. Major changes made to the standard in this revision include the following: inclusion of the liquid form of monosodium phosphate; inclusion of a requirement for compliance with the Safe Drinking Water Act and other federal regulations (Section 4); and, inclusion of a requirement for tamper-evident packaging (Sec. 6.2.3 and 6.2.4).