What type of building is considered the most dangerous in the U.S.?

Vacant buildings are often considered the most dangerous due to several factors that increase the risks associated with firefighting and building safety. These structures frequently lack proper maintenance, which can lead to deteriorated conditions, such as weakened floors or compromised structures. Additionally, they are typically unmonitored and may harbor hazardous materials, debris, or illegal activities, such as squatting or drug use, which can add to the dangers present at a fire scene.

Without occupants, there is also a greater chance that a fire might go unnoticed for a longer period, allowing it to grow larger and more dangerous before it is reported or extinguished. Firefighters responding to these buildings face the risk of unexpected hazards, such as hidden fire spread or structural collapse, making their job significantly more perilous.

In contrast, occupied commercial buildings, residential structures, and high-rise buildings, while they have their own dangers, typically have more established safety measures in place, such as fire alarms, regular maintenance, and occupancy, which allow for quicker personal evacuation and enable a safer firefighting strategy.