What is a key function of negative-pressure ventilation?

Negative-pressure ventilation is primarily designed to create a draft that pulls smoke, heat, and toxic gases out of a structure. This technique utilizes the principle of reducing the air pressure inside a building compared to the outside atmosphere, causing outside air to be drawn in and, in turn, pulling the smoky air away from the interior space. This is particularly effective during firefighting efforts, as it helps clear visibility and reduces the risk of smoke inhalation for both occupants and firefighters.

The process is essential for improving conditions inside the structure, allowing for safer navigation and more efficient firefighting tactics. While enhancing the overall firefighting effort and establishing a controlled environment are important aspects of fire operations, the primary and most direct function of negative-pressure ventilation is the ability to effectively remove harmful smoke and gases from the scene.