In this article, air filtration experts from Camfil explain the importance of air ventilation within a room and how to calculate air changes per hour (ACH).
What Does Air Changes Per Hour (ACH) Mean in Air Filtration?
Air changes per hour, which is often abbreviated as ACH, is a calculation of how many times per hour the entire volume of air in a given space is replaced with supply and/or recirculated air. It is also sometimes referred to as “air change rate” or “air exchange rate.”
Why Do You Need to Calculate ACH?
Air changes per hour are important in determining if a space is getting adequate ventilation. Additionally, if you have chosen to implement air purifiers to improve air quality and lower the risk of COVID-19, ACH will help you determine which devices are appropriate for your application, as well as how many you need.
Ventilation is important for the indoor air quality (IAQ) inside a building. Improper ventilation can lead to a buildup of pollutants in indoor spaces, which is detrimental to the health of building inhabitants. According to the EPA (1), negative health effects of poor indoor air quality include:
- Irritation of the eyes, nose, and throat.
- Headaches, dizziness, and fatigue.
- Respiratory diseases, heart disease, and cancer.
Polluted air also leads to moodiness and decreased productivity for employees and reduced learning for students in school.
Additionally, the EPA asserts that increasing ventilation is an important strategy for decreasing the...