The production of hydrogen through biomass gasification became one of the favored methods in the field of renewable energy generation. Yet, safety issues that might arise along the process are still uncertain. The present study performed preliminary risk assessment for the bench scale of In-situ Catalytic Adsorbent (ICA) gasification unit to identify possible risk in the process plant. Through HAZOP study, gasifier is identified to give the highest possible risk. With the aid of DNV's PHAST software the dispersion and consequences of the escape gas are determined. Preliminary safety assessment presented in this paper contributes to the identification of possible hazardous event concerning toxic exposure, fires and explosions for biomass process industry. © 2011 IEEE.