This training unit on fire behavior is part of a 17-unit course package written to aid instructions in the development, teaching, and evaluation of fire fighters in the Wisconsin Fire Service Certification Series. The purpose stated for the 8.5-hour unit is to assist fire fighters in gaining an understanding of fire behavior--chemistry of the fire, flame spread, flashover, phases of burning, classes of fire, heat transfer, and extinguishing agents. An instructor's guide sheet provides this information: introduction to the topic, instructor preparation, length of unit, methods of instruction, testing, equipment and facilities required, recommended visual aids, and references. Following a list of unit objectives, a lesson plan outlines the main teaching points and states the preferred teaching method, cites the reference and page number(s) where the information is to be found, and indicates the necessary handouts. Other contents in the unit include a unit quiz, answer key to the quiz, and handouts (graphs, student worksheets, informational material, and forms). (YLB)