In fire behavior, what does the term "pyrolysis" refer to?

The term "pyrolysis" specifically refers to the thermal decomposition of organic materials when they are subjected to high temperatures in the absence of oxygen. This process occurs prior to actual combustion and involves the breakdown of larger molecules into smaller, volatile compounds and gases. Pyrolysis is a critical phase in fire behavior, as it contributes to the generation of flammable gases, which can ignite and sustain a fire.

Understanding pyrolysis is essential for firefighters because it provides insight into how materials will behave under heat, helping them to predict fire spread and intensity. The other options do not accurately describe pyrolysis; they touch on concepts related to fire behavior but do not reflect the specific process of thermal decomposition that pyrolysis denotes.