What clue helps determine where a fire started?

The presence of a V pattern is a crucial indicator for determining the point of origin of a fire. Fire tends to spread in a way that creates this distinctive shape, with the apex of the V pointing toward the source of the ignition. As a fire burns, it consumes available fuel, and the V pattern forms due to the way heat rises and the intensity of the flames radiating from the origin. This behavior is attributed to the principle that fire grows upwards and outwards, making it possible for investigators to trace the path and locate the initial burn area effectively.

In contrast, other patterns like a spiral, straight line, or circular patterns do not hold the same significance when identifying an origin point. These formations could result from various factors such as wind direction or the layout of combustible materials, making them less reliable as indicators of where the fire started. Therefore, recognizing the V pattern is essential for fire investigators looking to establish the origins and causes of a fire incident.