Where should the exhaust opening be located when performing Positive Pressure Ventilation (PPV)?

The location of the exhaust opening during Positive Pressure Ventilation (PPV) is crucial for effectively removing smoke and heat from a structure. Placing the exhaust on the leeward side takes advantage of the wind dynamics, allowing fresh air to enter from the windward side and push the smoke and heat toward the exhaust. This configuration helps optimize airflow across the fire area, enhancing the overall efficiency of the ventilation process.

Positioning the exhaust on the leeward side also minimizes the chance of wind-driven flames or embers being pushed back toward the crew, reducing the risk of backdrafts or further fire spread. By ensuring that the smoke moves from high-pressure areas (the fire) to low-pressure areas (the exhaust), responders can maintain safer working conditions and improve visibility within the structure.

In contrast, placing the exhaust opening on the windward side could disrupt the intended airflow pattern and hinder smoke removal, as the wind may carry smoke towards the area that needs to be ventilated rather than away from it. Additionally, choosing a specific distance from the fire or the highest point of the building does not account for the critical need for matching the exhaust to the flow of air entering from the opposite side to effectively clear smoke and heat.