What characterizes a fuel-controlled fire?

A fuel-controlled fire is characterized by the limited availability of combustibles, which refers to the materials that can ignite and sustain a fire. In this scenario, the intensity and duration of the fire are primarily dictated by the quantity and type of fuel present. When the fuel is exhausted or depleted, the fire will diminish or extinguish, regardless of the oxygen levels, which may be sufficient for combustion.

In contrast, if a fire were limited by the amount of oxygen, it would be classified as an oxygen-controlled fire. A fire that can spread indefinitely is not limited by either fuel or oxygen, and instead, it may have adequate supplies of both, leading to uncontrolled growth. Lastly, a fire requiring constant ventilation often pertains to conditions where airflow influences the combustion process, but this does not describe the core characteristic of being fuel-controlled. Thus, option B accurately captures the essence of a fuel-controlled fire.