There are those who discount aggressive search operations at fires in Abandoned or “Vacant” structures because “It's vacant, there’s no one in there, why risk it…” A fire in an abandoned building actually presents MORE evidence of being occupied than a fire in a typical inhabited structure. Here’s why:
Consider the structures. Occupied dwellings have means of spontaneous combustion that do not require human intervention. Electrical and gas services can malfunction or allow for appliances to run while occupants are not present, or cooking to be left unattended. A fire in an abandoned structure almost exclusively relies on direct human action for ignition. Barring an act of God, there is no reason for such a structure to catch fire WITHOUT human effort.
Consider the occupants. Individuals who own or rent homes are more likely to be competent, healthy, independent people, capable of exiting an emergency situation given adequate warning. Those who squat in abandoned structures are more likely to be physically or mentally ill, intoxicated, or otherwise impaired creating barriers to the recognition of danger. Squatters have a higher likelihood of smoking or using unsafe methods to stay warm in winter. They don’t leave the stove on when they run errands or forget to clean the lint trap in the dryer.
Is there a human trapped inside every fire in an abandoned structure? Of course not, but logic suggests the fire itself is strong evidence they may be there. I’ve been to lots of fires in “vacant” structures. Only one was ever an act of God, but I’ve been to many that resulted in rescues or fatalities. Don’t write them off based on the appearance of occupancy.