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. Essential in industrial hygiene for assessing workplace exposure and ensuring compliance with safety regulations. Also utilized in research studies involving halogenated hydrocarbons and their environmental fate.