Combustion and combustion conditions. Thermodynamics of the burning processes. Stoichiometric combustion equation, calculation the required amount of oxygen and air, combustion products and heat capacity. The kinetics of the combustion processes. Complete and incomplete combustion. Heat as a cause of fire. Heat transfer, heat conduction. Calculation of the heat amount, heat flow, and temperature regime. Gas combustion. Burning gas substances, activation energy, self-ignition and self-ignition temperature, burning, sources of burning, the burning energy. Explosive combustion of gasses, pressure and temperature of explosion. Liquid combustion. Combustion mechanisms, ignition temperature, self-ignition temperature, flammable limits. Solid materials combustion. The properties that affect flammability of the burning mechanisms of solids, burning temperature and auto ignition. Combustible dust, conditions of explosive combustion, explosion index. Self-heating and self-ignition, self-heating and self-ignition conditions, biological self-heating.