Which window should be opened first for effective natural ventilation?

For effective natural ventilation, the best practice is to open the window on the downwind side first. This method utilizes the natural airflow patterns created by the wind. By opening the downwind window, you allow the smoke and heat to exit freely, which enhances the overall flow of fresh air from the upwind side into the structure.

Opening the downwind window first helps to create a negative pressure area in that section of the building, pulling air in from the upwind side and facilitating the movement of smoke away from the fire area. This is particularly important in firefighting operations where managing smoke and heat is crucial for visibility and safety.

Choosing the downwind side ensures that the benefit of natural ventilation is maximized, as air will flow from areas of higher pressure (upwind side) to lower pressure (downwind side), effectively clearing the environment for both firefighters and any potential victims.