What must a fire investigator consider when interpreting fire patterns?

When interpreting fire patterns, considering the position of the fire in relation to walls and corners is essential because fire behavior is significantly influenced by the layout of a structure. The interaction between fire and physical features such as walls and corners creates distinct patterns, which can reveal critical information about how the fire spread and where it originated. For example, fires typically burn upward and outward from their ignition point, and observing how the heat and flames interacted with the walls can help in determining these aspects. Investigators analyze these patterns to reconstruct the sequence of events leading to the fire's development.

The other factors, while they may provide contextual information about the fire scene, do not directly impact the interpretation of fire patterns to the same extent. The age of the building might influence construction materials and methods but does not directly inform how fire spreads in relation to specific physical features. Similarly, the color of smoke can indicate the materials burning but does not provide concrete evidence about fire patterns themselves. The type of fire alarm installed is relevant to the response to the fire but does not contribute to understanding the fire dynamics or patterns left behind by the flames. Thus, the relationship of the fire to structural elements is paramount in the investigation process.