there is no doubt that human being needs to become integrated with industry and industry needs to be progressed, daily. on the other hand, serious events in industrial units specially in oil industries has been shown that such damages and events are industry related ones. the consequence of such events and damages which resulted in chemical and poisoned explosions and loss of life and property have caused that industrial engineers and designers looking for increasement of their units safety and using new standards and re-designing and strengthening their industrial units. then, various methods and software’s were created in order to predict and prevent of such events by which we can assist and analyses events in an operational unit. this present thesis have described the consequence assessment and it have analyzed the release and emission of sour gas( methane along with lots of hydrogen sulfide) in high pressure in the injection to oil holes and all results have been acquired and analyzed by software phast which is one of the most related software’s .this study shows that in case of gas leakage in the worst possible states (in case of environmental conditions), place will be filled with hydrogen sulfide to 10km distance from the release point , in case of explosion ,it will reach to 550 m and in case of jet fire , 70m distance will be under its effect.