Used in analytical laboratories for calibration of instruments such as spectrophotometers and ion chromatographs to accurately measure phosphate concentrations in water, soil, and biological samples. Commonly applied in environmental testing to monitor nutrient levels in wastewater, lakes, and rivers, helping to assess eutrophication risk. Also utilized in industrial processes, including boiler water treatment and food and beverage quality control, to ensure compliance with regulatory standards. In research and clinical settings, serves as a reference for enzymatic assays and phosphate metabolism studies.