Abstract: In this paper, simulation of jet fire in the splash zone due to 30″ riser leakage are performed by 3D CFD fire modelling software KFX to study the impacts of the jet fire on people safety and platform structure. The radiation flux of jet fire caused by 20 mm and 50 mm orifices leakage and rupture are analyzed as well as the influence to escape route, living quarter, life boat, helideck, platform structure and other risers. The simulation results show that the jet fire impacting area due to 20 mm and 50 mm orifice leakage is limited because of the obstruction of platform decks and blockage. The jet fire would not impair the escape route on platform significantly, but the escalation potential of other risers should be taken into consideration. The jet fire due to riser rupture would cause impairment of the platform structure. Ignition source isolation and shut down of the riser are the effective measures to mitigate the riser rupture accident.