Natural horizontal ventilation is effective under which condition?

Natural horizontal ventilation is most effective when atmospheric conditions are favorable. This refers to scenarios where factors such as wind direction, temperature, and the absence of barriers allow fresh air to flow into a structure while pushing smoke and heat out. When there is a undisturbed wind flow, it can carry smoke away from the building, thereby aiding in reducing heat and improving visibility for occupants and emergency responders.

In contrast, using electrical fans can create forced ventilation, which is different from natural ventilation, and may not rely on atmospheric conditions. The presence of smoke signals that a fire is occurring, but it does not influence the effectiveness of natural ventilation directly. Thermal imaging is a useful tool for locating hotspots or areas affected by fire but does not relate to the mechanism of natural ventilation itself. Therefore, understanding the influence of atmospheric conditions is crucial in applying natural horizontal ventilation effectively.