Local Adaptation of Hourly Allocation Coefficients for VOCs Emissions from Oil Depots and Calculation of Atmospheric Environmental Protection Distances

• • Temperature-dependent hourly allocation coefficients for VOCs emissions from oil depots were established: coefficient peaks at 0.068 for temperatures >14 °C and drops to 0.007 for temperatures <8.5 °C, enabling seasonally accurate emission inventories. • • Annual VOCs emissions from the studied depot were 256.13 t, with summer (108.89 t) contributing 42.51% and winter (12.54 t) only 4.90%, a seasonal disparity of 8.68-fold that must be captured in air quality modeling. • • Dynamic source strength modeling increased the maximum hourly VOCs concentration by 55.12% (from 1445.8 to 2242.7 μg/m³) and expanded the atmospheric environmental protection distance by 450 m (from 0 to 450 m) compared to constant source assumptions. • • The exceedance area under dynamic conditions was 0.03 km², whereas constant source modeling predicted zero exceedance, highlighting the risk of underestimating health impacts if temporal variability is ignored.