During which phase is a fire considered to be in the incipient stage?

A fire is considered to be in the incipient stage during the initial phase of its development, which is often termed Phase 1. This is the stage where the fire is just beginning, typically characterized by the presence of smoke and the initial generation of heat from the ignition source, but the flames have not yet fully developed or spread.

In this stage, the fire is generally small enough that it can be easily controlled or extinguished, and it has not yet reached the point where it poses a significant risk to life or property. Understanding this phase is critical for fire investigators as it allows them to analyze the origins of the fire and the materials involved in ignition during the early moments of the fire's lifecycle. Recognizing these characteristics is essential for investigating how fires start and how they can be effectively managed in their early stages.