What is the minimum outdoor airflow rate based on?

The minimum outdoor airflow rate is primarily based on the number of occupants and the rate of fresh air required per person. This approach is grounded in ensuring sufficient ventilation to maintain indoor air quality, as well as to dilute potential indoor pollutants generated by activities such as breathing, cooking, and the use of building materials.

When determining the required airflow, building codes and standards often specify a certain amount of outdoor air that should be provided for each person in the space. This helps to accommodate the needs of individuals and ensure that the indoor environment remains healthy and comfortable. For instance, in commercial spaces with high occupancy, careful consideration of the number of occupants and the appropriate ventilation rates is essential to avoid issues such as stuffiness and high levels of carbon dioxide.

The size of the ventilation system, type of building usage, and amount of outdoor air available are factors that can influence the design and efficiency of the ventilation system but do not directly determine the minimum outdoor airflow rate. The focus on occupant-based requirements highlights the importance of addressing human health and comfort in building ventilation practices.