Which of the following is a type of mechanical ventilation system?

Mechanical ventilation systems are designed to control the flow of air in a space, ensuring a comfortable and safe environment by actively moving air rather than relying solely on natural forces. The correct response, which identifies a type of mechanical ventilation system, emphasizes a crucial characteristic: it combines methods of air intake and exhaust.

Specifically, the combination of natural air intake and mechanical exhaust refers to a system where fresh air is brought into the space via natural means, such as through openings or vents, while the stale or polluted air is removed by mechanical means, typically involving fans or blowers. This setup is effective in creating a controlled environment where air quality can be better managed, allowing for regulated airflow and enhanced comfort.

In contrast, purely mechanical systems utilize power-driven devices for both intake and exhaust, while natural ventilation relies primarily on external environmental conditions, like wind and temperature differences. Passive ventilation involves methods that do not use mechanical means at all, such as simple windows or louvers, which depend on natural air movements.

The correct answer acknowledges the integration of these strategies, illustrating an effective approach to mechanical ventilation that balances both the entry of fresh air and the removal of stale air.