The high-volume velocity fan should be placed on which side during positive pressure ventilation?

The correct placement of the high-volume velocity fan during positive pressure ventilation is on the windward side. This side is characterized by being the direction from which the wind is coming. By placing the fan on the windward side, the airflow created by the fan can effectively push air into the structure, which is critical for enhancing ventilation and removing smoke and heat.

Establishing positive pressure in this manner helps drive the smoke and toxic gases out of the building, creating a safer environment for both firefighters and potential victims inside. The fan operates by directing fresh air into the structure, which can aid in pushing out hot gases and smoke effectively, thus improving visibility and conditions for interior operations.

In contrast, placing the fan on the leeward side, downwind, or crosswind would not provide the same effectiveness. On the leeward side, the airflow would be hindered, making it difficult to introduce fresh air. Meanwhile, positioning the fan downwind or crosswind does not leverage the natural air movement, making it less effective for achieving the desired positive pressure needed for efficient ventilation.