Ventilation is defined as which of the following?

• A. The Process Of Supplying Air To Or Removing Air From A Space For The Purpose Of Controlling Air Contaminant Levels, Humidity, Or Temperature Within The Space
• B. The Process Of Supplying Air To Or Removing Air By Natural Or Mechanical Means To Or From Any Space, Not Necessarily Conditioned
• C. The Process Of Heating Air
• D. The Process Of Cooling Air

Answer: (A)

Ventilation is the intentional exchange of indoor air with outdoor air, achieved by supplying air to a space and removing air from it, with the goal of controlling air contaminant levels, humidity, or temperature within that space. This definition emphasizes the purpose of moving air to maintain acceptable indoor air quality and comfort, not just to change the air’s temperature. Heating or cooling alone changes the air’s properties but does not by itself ensure the necessary air exchange to dilute contaminants or manage humidity. Natural or mechanical methods of air movement are both possible, but the defining idea is using air exchange to control contaminants, humidity, and temperature. A broader notion of ventilation that doesn’t tie the air movement to these control objectives is less precise for this context.