Cooperative Personnel Services Firefighter (CPS) Practice Exam 2026 - Free Firefighter Exam Questions and Study Guide

In the context of deflagration, Pmax represents the maximum pressure developed during the combustion process. Deflagration is a subsonic combustion wave that typically propagates through a gas or a solid at a speed slower than the speed of sound, as opposed to detonation, which occurs at supersonic speeds.

During the process of deflagration, as fuel combusts, it generates heat and expands rapidly, creating pressure waves. Pmax quantifies the peak pressure observed at the point of maximum combustion output. This parameter is critical for understanding the behavior of combustion systems, particularly in designing safety measures and defining the limits of materials that can withstand such pressures without failure.

While the other options refer to important concepts within the study of combustion, they do not directly relate to Pmax. The minimum ignition energy refers to the smallest amount of energy needed to ignite a fuel-air mixture, the temperature at ignition indicates the temperature necessary for a fuel to ignite, and the amount of combustible material speaks to the quantity of fuel involved in the reaction. However, none of these options describe what Pmax specifically measures in the context of deflagration.