Abstract: The damage radius of a chemical fertilizer plant,which produces 150 000 tons annually,generated by the blast wave of the physical explosion and the total explosion were estimated and compared in this paper.The results show that the damage radius of the blast wave from the total explosion is much bigger than that from the physical explosion.And the descending sequence device of the damage radius generated from the blast wave of the physical explosion is the waste heat boiler,the ammonia converter,the water cooler,the cold exchanger,the ammonia separator Ⅰ,the ammonia separator Ⅱ,the heat exchanger,the ammonia cooler,the oil separator and the recycling machine,and the device of the sequence generated from the blast wave of the total explosion is the water cooler,the ammonia separator Ⅱ,the cold exchanger,the heat exchanger,the ammonia separator Ⅰ,the oil separator,the ammonia converter,the waste heat boiler,the ammonia cooler and the recycling machine.The calculation results can provide a theoretical guidance for the daily safety production and management.