An Integrated CFD-Probit Framework for Human Safety Zones in LNG Bunkering Operations: Comparing Deterministic Thresholds and Probabilistic Injury Modeling

The global push for maritime decarbonization has accelerated LNG adoption as a marine fuel due to its lower carbon emissions and compliance with strict environmental regulations. However, LNG bunkering poses significant safety risks from its cryogenic temperature (−162 °C) and flammability, potentially causing frostbite, fires, or explosions upon leakage. This study introduces a novel safety zone framework that integrates CFD-based gas dispersion and fire simulations with threshold criteria and Probit injury modeling. CFD analyses yielded time- and space-resolved distributions of temperature, gas concentration, heat flux, and overpressure, which were applied to threshold values and Probit equations to quantify injury probability and severity, enabling spatially resolved hazard zones. Threshold methods proved conservative, while Probit modeling provided a quantitative foundation, with thresholds serving as complementary tools. The results offer practical guidance for identifying high-risk areas, strengthening LNG bunkering safety regulations, and improving emergency response strategies.