What is your last warning sign before flashover?

Rollover is considered the last warning sign before a flashover occurs. It manifests as flames igniting within the upper layer of smoke and heat in the compartment, indicating that the combustible gases are beginning to ignite due to the high temperatures present. This phenomenon results from the accumulation of unburned fuel in the form of smoke and other gases that become heated to their ignition temperature.

When rollover occurs, it signifies that the environment is reaching critical conditions, indicating an imminent flashover. Flashover represents a rapid fire spread where virtually all combustible materials in the area ignite almost simultaneously, making it a highly dangerous situation for firefighters.

Understanding this warning sign is crucial for fire personnel, as it allows them to recognize the need for immediate tactical changes to protect themselves and effectively manage the incident. The other options describe different fire behaviors, but they are not the last indicators of flashover, highlighting the significance of recognizing rollover in fire dynamics and safety protocols.