What type of ventilation system works by drawing outdoor air through openings into a space?

Natural ventilation is characterized by its reliance on passive air movement, utilizing outdoor air that enters through openings such as windows, doors, or vents. The effectiveness of natural ventilation is highly influenced by factors like wind, temperature differences, and the design of the building, which allow fresh air to circulate without the use of mechanical systems. This method is eco-friendly and cost-effective since it minimizes energy consumption associated with air conditioning and heating systems.

In contrast, mechanical ventilation involves powered systems, such as fans and blowers, to actively move air in and out of a space. Hybrid ventilation combines both natural and mechanical methods, enabling more efficient air exchange under varying conditions. Forced ventilation also signifies a mechanical process but typically focuses on creating pressure differences to move air, rather than simply allowing it to flow freely like natural ventilation does. Thus, identifying the distinction is crucial, and the correct answer reflects an understanding of these principles.