Increasing public interest in air pollutants driven by climate change and high concentrations of particulate matter (PM) has

highlighted the importance of managing pollutants, such as SO 2 , NO 2 , and benzene. These compounds are known precursors

of secondary PM that aff ect the climate and human health, with benzene being particularly carcinogenic. Benzene is a

volatile organic compound (VOC) that can persist in the atmosphere for approximately 9.4 days, potentially traveling long

distances and contributing to the generation of secondary organic aerosols (SOAs) through photochemical reactions, leading

to elevated fi ne dust concentrations. To comprehensively manage emissions, leaks, and point sources, a fence line monitoring

study was conducted at petroleum refi ning industrial complexes in Daesan-eup, Chungcheongnam-do, and Yeosu-si,

Jeollanam-do in Korea. Ultraviolet Diff erential Optical Absorption Spectroscopy (UV-DOAS) technology was used to confi

rm measurement reliability and monitor emissions. High SO 2 concentrations emitted in a specifi c direction were identifi ed

at the Yeosu-si, and further investigation identifi ed the fl are stack of a suspected plant as the emission source. Fence line

monitoring was eff ective in identifying and addressing unknown high-concentration emission sources and devising measures

to manage fugitive emissions and leaks.