During a fire event, what condition indicates that a structure may be at risk of collapse?

A sagging roof or floor is a significant indicator that a structure may be at risk of collapse during a fire event. This condition suggests that the structural integrity of the building is compromised, often due to the intense heat from the fire weakening the materials such as wood, metal, and concrete. When these structural components can no longer support their own weight or the weight of additional elements, such as water or firefighting equipment, there's a heightened risk of failure.

Recognizing signs of sagging is crucial for the safety of firefighters and others in the vicinity. It requires immediate action, such as evacuation and reassessment of firefighting strategies, to ensure safety while continuing to address the fire. This awareness helps mitigate the potential for injury and damage during firefighting operations.