Fire or smoke damage to property, regardless of the "size" of the fire, also requires an immediate response. Soot residue is highly acidic and can cause irreversible property damage if it is not treated as an emergency. Soot residue can cause the metal in doorknobs, plumbing fixtures, light fixtures, etc., to pit or corrode. Glass in windows, mirrors, and cabinets can be etched by soot residue, causing them to look cloudy and soiled. Plastics, appliances, vinyl windows and fabrics can be discolored by soot residue.