What is meant by ACH, or air changes per hour?
- Abby!Lv 41 decade agoFavorite Answer
Air Changes per Hour (ACH) refers to the number of times per hour that the entire air volume of the enclosure is changed. It is measured relative to a specific room pressure, usually 50 Pa.
- #7Lv 61 decade ago
ACH is the number of times in a one-hour period that the air in a given space (a room, a building, an airplane cabin, etc.) is completely replaced by new air. The sites listed below can show you some standard applications of the data.