Which factor does not contribute to interior flame spread?

The factor that does not contribute to interior flame spread is oxygen consumption. While oxygen is essential for combustion, its consumption doesn't directly correlate with the propagation of flames within an interior space. Instead, it addresses the availability of oxygen for sustaining the fire rather than impacting how quickly flames spread across surfaces.

The other factors listed play crucial roles in how fire spreads in an interior environment. The interior finish of materials affects the rate at which fire can develop and the heat release rate, which directly influences flame spread. Additionally, certain materials can add fuel to the fire, enhancing its intensity and potentially allowing it to spread more quickly. Moreover, interior finishes can also facilitate fire extension beyond the initial point of origin by providing pathways for flames and heat to reach new areas, further exacerbating the situation. Understanding these dynamics is essential for effective fire prevention and safety planning.