A fire that produces turbulent, dark smoke is most likely in what condition?

A fire that produces turbulent, dark smoke is indicative of a flashover condition. During a flashover, the temperature within the environment rises rapidly, causing combustible materials to ignite simultaneously. This intense heat leads to the production of dark, turbulent smoke due to incomplete combustion and the burning of synthetic materials, furnishings, and other fuels present in the environment.

This condition represents a critical and dangerous phase of a fire, characterized by rapidly spreading flames and the potential for significant fire behavior changes. The smoke is not only dark but dense, which is a direct result of the fire consuming organic materials and releasing various pollutants and particulates.

In contrast, a contained fire would show less chaotic smoke behavior, as it would be under control and not producing the extreme conditions present during flashover. An extinguished fire would smoke significantly less, if at all, as the fuel source has been eradicated. A ventilated fire can still produce smoke, but it tends to be less turbulent and darker than what is observed during a flashover, as proper ventilation can help clear out some of the heat and smoke. Thus, flashover is the most fitting condition for fire producing turbulent, dark smoke.