Question 238Safety & Environmental - 1st Asst/Chief

The correct answer is A) spontaneous combustion. Spontaneous combustion occurs when heat is generated by a chemical reaction within a substance, such as through oxidation or decomposition, and the heat continues to build up to the point of ignition without an external source of heat or flame. This is the process described in the question. The other answer choices are incorrect because: B) Radiation ignition refers to ignition caused by exposure to radiant heat, not an internal chemical reaction. C) Chemical ignition refers to the actual ignition process, not the preceding buildup of heat. D) Chemical combustion is the overall process of a chemical reaction producing heat and flame, not specifically the preceding buildup of heat.