How many air changes per hour are typically required to prevent stagnant regions of air?

To prevent stagnant regions of air in a space, it is generally accepted that achieving 8 to 10 air changes per hour is effective. This level of air movement helps ensure that the indoor air quality is maintained and that air pollutants are adequately diluted and removed from the environment.

As spaces require ventilation to ensure fresh air circulation, higher air change rates can contribute to better comfort levels and minimize issues like mold growth or the buildup of contaminants. While lower rates, such as 4 to 6, might suffice for certain scenarios, they may not effectively eliminate stagnant areas, particularly in larger or poorly ventilated spaces. Therefore, the guidance of 8 to 10 air changes per hour is a standard benchmark for various building types to promote proper air distribution and maintain overall air quality.