What Is the Difference between ACH and e-ACH?

Air changes per hour, abbreviated ACPH or ACH is a measure used in ventilation calculations to measure the amount of ‘new’ air added or removed from a room. 

Equivalent air changes per hour, or e-ACH, on the other hand is a measurement of the ‘equivalent’ amount of air a purifier changes per hour. Air purifiers do not actually bring in new air into a room, or change the air in a room. Instead, they clean the air already existing in the room. 

Learn more about: How to calculate an air purifiers equivalent air changes per hour (e-ACH) »

Get Your Free Guide to Breathing Safe

Join the thousand keeping up on the latest research & knowledge on how to breathe safe. Sign up now and receive a free guide to breathing safe!

Was this article useful?00

Leave a Comment

Smart Air is a social enterprise that creates simple, no-nonsense air purifier and provides free education to protect people’s health from the effects of air pollution. We are proud to be the only certified B-Corp dedicated to fighting air pollution.