When ventilating a flat roof, how far should aerial ladders be extended above the roof level?

The recommended height for extending aerial ladders above the roof level is six feet (2 meters). This allows the firefighter to have a safe and stable platform from which to work while providing enough height to clear the parapet or edge of the roof for safe egress and entry.

Extending the ladder six feet above the roof level gives operators enough room to maneuver safely and easily get onto the roof without the risk of being too close to the edge, which can be a safety hazard, especially in conditions where the roof is unstable or if there is a fire situation requiring the operator to quickly escape. This practice helps facilitate safe operations and ensures that firefighters can work effectively and with reduced risk of falling.

Other options suggest varying heights, but six feet is deemed the most effective for providing a safe working height while also ensuring that the ladder is not extended excessively, which could compromise stability or accessibility.