In mechanical ventilation, what is the primary function of introducing outside air?

The primary function of introducing outside air in mechanical ventilation is to dilute indoor pollutants. This process helps maintain a healthy indoor environment by ensuring that concentrations of harmful substances, such as volatile organic compounds (VOCs), carbon dioxide, and other airborne contaminants, are kept at manageable levels. By bringing fresh air from outside into the building, the system can effectively reduce the accumulation of these pollutants, improving overall air quality and promoting the well-being of the occupants.

While outside air can also affect temperature, humidity levels, and noise reduction, those are not its principal roles. The main focus of venting fresh air is to enhance indoor air quality through dilution, ensuring that occupants have access to clean and safe air to breathe. This is particularly crucial in commercial settings where activities might generate various pollutants, requiring adequate ventilation to support a healthy environment.