The paper presents a Computational Fluid Dynamics (CFD) approach to major – hazard studies, by applying a finite-domain technique to predict the dispersion of combustion products (CO, SO2, smoke, Volatile Organic Compounds, VOC, Polycyclic Aromatic Hydrocarbons, PAH, etc.) from fuel-tank fires, as well as the toxic plume rise.Furthermore, a methodology is presented for the identification of risk zones for the first respondents (fire fighters). Numerical simulations were performed with the use of the SIMPLEST algorithm, a second-order accurate MUSCL scheme with deferred correction for the convective terms in the momentum equations, CUPID for the convective terms in the scalar conservation equations, and a modified, RNG k-ε, two-equation turbulence model. Radiation was computed by a discrete transfer model. Various scenarios were examined and the results are presented and discussed.