On this episode of "Random" HVAC words or phrases, we tackle Air Changed Per Hour or ACH. Check out this article for more info. https://cleanair.camfil.us/2021/10/22/how-to-calculate-air-changes-per-hour/ http://www.cintas.com/HVACKnowItAll. Save 8% on your purchase https://www.trutechtools.com/ with promo code knowitall Check out the HVAC Know It All app app.hvacknowitall.com https://www.hvacknowitall.com/pages/about Visit HVAC Know It All on social media Facebook https://www.facebook.com/hvacknowitall/ Instagram https://www.instagram.com/hvacknowitall1/