At what percent of oxygen will combustion cease?

Combustion is the process of burning, which requires three essential components: fuel, heat, and oxygen. Oxygen levels in the environment play a critical role in sustaining combustion. Generally, the minimum concentration of oxygen required to support combustion is around 16%. Below this threshold, the ability of a fire to continue burning diminishes significantly.

Among the given options, the choice indicating 6-10% encompasses a range where combustion would not be able to sustain itself. Oxygen concentrations in this range are insufficient to maintain a chemical reaction that supports combustion. Fires require a minimum of about 16% oxygen concentration to continue burning effectively. Therefore, when the oxygen level falls to 11-15%, effectively combustion may begin to struggle, but it is still possible in some circumstances, particularly with certain materials or under specific conditions. Ultimately, as oxygen levels drop to the range of 6-10%, combustion will largely cease.

Understanding this concept is crucial for fire behavior analysis, especially in scenarios involving fire suppression and safety in environments with varying oxygen availability.