Used as a reference standard in analytical laboratories for the calibration of instruments such as ion chromatographs and ion-selective electrodes. Ensures accurate measurement of iodide concentrations in environmental, pharmaceutical, and food samples. Commonly applied in water quality testing to monitor iodide levels in drinking water and wastewater. Supports quality control in clinical labs for thyroid function studies where precise iodide quantification is critical. Also used in research and development for method validation and traceability in iodine speciation studies.