Used as a reference standard in analytical laboratories for the detection and quantification of phenanthrene in environmental samples such as water, soil, and air. Commonly employed in gas chromatography (GC) and high-performance liquid chromatography (HPLC) to calibrate instruments and validate methods. Essential in monitoring polycyclic aromatic hydrocarbon (PAH) contamination, especially in industrial emissions, wastewater, and polluted sites. Also used in research studies assessing the fate and behavior of PAHs in ecosystems and in evaluating the efficiency of remediation processes.