Which statement correctly lists the four stages of fire development and identifies the stage with the highest flashover risk?

Which statement correctly lists the four stages of fire development and identifies the stage with the highest flashover risk?

• A. Ignition, growth, fully developed, and decay; flashover risk is highest as the fire nears the fully developed stage.
• B. Incipient, growth, fully developed, and decay; flashover risk is highest as the fire nears the fully developed stage.
• C. Incipient, growth, flashover, decay; flashover risk is highest during growth.
• D. Latent, combustion, fully developed, decay; flashover risk is highest during combustion.

Answer: (B)

Understanding how fires develop helps anticipate hazards like flashover. There are four stages: incipient (the fire just starts, heat release begins); growth (flames spread, heat release climbs); fully developed (maximum heat release, room filled with hot gases, conditions ripe for flashover); decay (fuel wanes, heat release falls). The risk of flashover increases as the fire nears the fully developed stage, peaking at the transition into that stage. The sequence incipient, growth, fully developed, and decay matches this pattern and the statement about flashover risk being highest as it approaches the fully developed stage is the best description. Other sequences use nonstandard terms or place flashover in a different phase, which doesn’t align with how fire behavior typically unfolds.

Understanding how fires develop helps anticipate hazards like flashover. There are four stages: incipient (the fire just starts, heat release begins); growth (flames spread, heat release climbs); fully developed (maximum heat release, room filled with hot gases, conditions ripe for flashover); decay (fuel wanes, heat release falls). The risk of flashover increases as the fire nears the fully developed stage, peaking at the transition into that stage. The sequence incipient, growth, fully developed, and decay matches this pattern and the statement about flashover risk being highest as it approaches the fully developed stage is the best description. Other sequences use nonstandard terms or place flashover in a different phase, which doesn’t align with how fire behavior typically unfolds.