Name two typical roof types firefighters may encounter on vertical ventilation and a key concern for each.

• A. Flat roofs — blow-through risk and rapid fire spread. Pitched roofs — fall hazards and variable deck strength.
• B. Flat roofs — fall hazards; Pitched roofs — blow-through risk.
• C. Flat roofs — minimal risk; Pitched roofs — no deck strength concerns.
• D. Flat roofs — blow-through risk; Pitched roofs — stable deck strength.

Answer: (A)

Vertical ventilation hinges on matching your roof cut to the fire’s behavior and the hazards you’ll face on the roof. Flat roofs are prone to blow-through and rapid fire spread because there’s no sloped surface to slow or contain heat, so the fire can push into the attic or through the roof deck quickly if you create an opening. Pitched roofs bring different dangers: fall hazards from the slope and work positioning, plus variable deck strength since the roof structure can change across the surface, with some areas weaker or more prone to collapse. This combination—flat roofs with blow-through and rapid spread, and pitched roofs with fall risks and inconsistent deck strength—best captures the typical concerns encountered during vertical ventilation.