Which is a sign that a structure is susceptible to collapse?

A structure that has doors stuck in shifted frames indicates a significant issue with its structural integrity. When a building shifts, it can be due to several factors, including shifting foundations, fire damage, or other structural failures. Doors that are misaligned and difficult to open often suggest that the framework of the building has been compromised, which is a strong indicator that the structure may be at risk of collapse.

This condition may be a result of the thermal expansion of materials due to excessive heat from a fire, which can weaken building components, or it may stem from damage that affects load-bearing elements. Recognizing these signs is crucial for firefighters, as operating in unstable environments can pose serious risks. Understanding these indicators helps in assessing the overall safety of the structure before entering or performing rescue operations.