What role does humidity play in fire behavior?

Humidity plays a significant role in fire behavior by directly influencing the ignition temperatures of materials. When humidity levels are high, the moisture content in materials increases, which can raise the temperature required for those materials to ignite. This means that in humid conditions, it may take more heat to start a fire, making ignition less likely. Conversely, low humidity levels can reduce the moisture content of fuels, making them more susceptible to ignition and allowing fires to spread more rapidly.

Understanding the effects of humidity is essential for firefighters to anticipate fire behavior in various environmental conditions. For instance, during dry and low-humidity conditions, fires can burn hotter and spread more quickly due to the increased availability of dry fuels. This knowledge aids firefighters in developing strategies for fire prevention, containment, and control based on the current humidity levels.