Which of the following is an imminent sign of flashover?

Flashover is a rapid transition from a fire that is localized in a compartment to a fully involved fire throughout the entire space. Recognizing imminent signs of flashover is crucial for firefighters to ensure their safety and effectiveness during operations.

The presence of smoke in the room serves as a critical indicator of fire activity. It can signal that combustion is occurring, and if the smoke is thick and dark, it may indicate a deeper level of the fire's intensity.

Rollover refers to the phenomenon where flames ignite combustible gases that accumulate in the upper layer of the room. This is a clear and visible signal of an imminent flashover, as the presence of these gases indicates that the fire is likely growing rapidly.

Intense heat is another obvious sign that a flashover may occur soon. When temperatures within a compartment rise to extremely high levels, it suggests that the materials present are nearing their ignition points, which can lead to sudden combustion throughout the space.

Collectively, all these elements—smoke, rollover, and intense heat—are critical indicators of an impending flashover. Their presence signifies that conditions are right for a rapid spread of fire, putting firefighters at risk. Understanding and recognizing these signs can help in making informed decisions about safety and tactics when combatting