The fire consumes kitchen cabinets, wood countertops and shelves stocked with plastic storage containers and dry goods like cardboard boxes of cereal, crackers, and cookies. More and more heat is generated. The temperature in the upper layer of hot gases rises to 400 degrees F—hot enough to kill people. Compounding the heat is a very dense smoke cloud hovering just a few feet above the floor. It may also include more toxic components like arsenic (used as a wood preservative) and lead (from old paint), as well as irritants like ammonia, oxides of nitrogen, hydrogen chloride and isocyanates.
The fire can now spread by two paths: direct flame contact or by auto-ignition, the temperature at which objects will spontaneously burst into flames without being touched by flames. The auto-ignition temperatures of hard and soft wood used in furnishings and home construction fall between 595 degrees F to 739 degrees F.