We have all heard that you are not supposed to throw water on a grease fire. But why? Well, according to Appleby Inspection Services the water, being heavier than the oil, sinks to the bottom where it instantly becomes superheated. The explosive force of the steam blows the burning oil up and out. Inside the confines of a kitchen, the fire ball hits the ceiling and fills the entire room. Also, do not throw sugar or flour on a grease fire. One cup creates an explosive force like dynamite.