In Pioneer Chlor Alkali v. National Union Fire Ins. Co. (D.Nev. 1994) 863 F. Supp. 1226, chlorine gas traveled through steel tubes, which passed through a liquefier. Brine was forced into the liquefier, cooling the chlorine gas into a liquid state. At some point, however, a rag became lodged in the liquefier, diverting the flow of brine and causing holes in the tubes. Brine passed through the holes, mixing with the chlorine, and the brine/chlorine mixture corroded the tubes, damaged equipment, and led to the emission of chlorine gas. The court concluded that a jury could reasonably find that the efficient proximate cause of the loss was the corrosion (an excluded peril) or the rag (a covered peril), and there was thus a triable issue of material fact precluding summary judgment.