Used as a reference standard in analytical chemistry for the detection and quantification of trans-1,4-Dichloro-2-butene in environmental samples, particularly in air and water testing. Commonly employed in gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) to calibrate instruments and validate methods for monitoring volatile organic compounds. Helps ensure accurate measurement of chlorinated hydrocarbon levels in industrial emissions, hazardous waste sites, and occupational safety assessments. Also used in research studies related to environmental degradation and byproduct formation in chemical processes.