What is an integral part of a fire investigation?

The observations of a firefighter are vital to fire investigations because they provide firsthand accounts of the incident, which can be crucial in determining the fire's origin and cause. Firefighters on the scene are trained to notice specific details such as the fire's behavior, smoke conditions, and any unusual patterns. Their observations can help link the physical evidence at the scene to the events leading up to the fire. Without these insights, it would be challenging to piece together the sequence of events and understand how the fire developed.

While the analysis of weather conditions, review of prior incidents, and maintenance of equipment are relevant to fire safety and prevention strategies, they do not hold the same immediate importance in the context of analyzing a specific fire event as the direct observations made by firefighters at the scene.