Used as a reference standard in analytical chemistry for the calibration of instruments such as gas chromatographs (GC) and mass spectrometers (MS). Ensures accurate quantification and detection of tributyl phosphate in environmental samples, industrial effluents, and nuclear fuel processing streams. Also employed in quality control for solvent extraction processes, where tributyl phosphate acts as an extractant for metal ions like uranium and plutonium. Helps maintain consistency in manufacturing and regulatory compliance testing.