Where should a fire investigator begin searching for the area of origin?

The area of origin of a fire is critically important for fire investigations, as it helps determine how the fire started and what materials were involved. The correct approach when beginning to search for the area of origin is generally to investigate the exterior of the fire before moving inward. This is because the exterior can provide vital clues, such as the fire's spread pattern and any signs of fuel sources or ignition points.

By starting at the exterior, investigators can observe the fire's point of origin relative to surrounding structures and objects. This examination can help identify whether the fire was deliberately set or if it was an accident, based on the presence of flammable materials or suspicious circumstances. Once the exterior is assessed, investigators can then work inward to gather more detailed information and analyze the conditions present within the structure.

This methodical approach ensures that the indicators of fire movement and potential points of ignition are not overlooked, which could lead to misinterpretations of the fire's development and cause. Therefore, starting the search at the exterior is a strategic decision for a thorough investigation.