Which of the following conditions can lead to a flashover?

A flashover is a rapid spread of fire throughout a space, resulting from the ignition of combustible materials due to the buildup of heat, especially through thermal radiation. High thermal radiation exposure to surfaces is a crucial factor because it raises the temperature of these surfaces to their ignition point. When enough fuel is available and the temperature reaches this critical level, all combustible surfaces within the area can ignite almost simultaneously, leading to flashover.

This phenomenon is essential in understanding fire dynamics, as recognizing the heat transfer involved can help in fire prevention and suppression strategies. The correct understanding of this condition highlights the importance of thermal management in the vicinity of a fire to prevent the risk of flashover.