Used as an analytical reference standard for the quantification and detection of pirimiphos-ethyl in environmental samples, biological specimens, and agricultural products. Commonly employed in chromatographic techniques like GC-MS and HPLC to ensure accurate measurement of residue levels in food crops, soil, and water. Also utilized in research settings to study pesticide degradation, metabolism, and regulatory compliance testing. Helps maintain quality control in laboratories involved in pesticide monitoring and environmental safety assessments.