Air Change Rate Calculator

Calculate air changes per hour (ACH) from airflow rate and room volume.

Supply or exhaust airflow.
CFM
Room length.
ft
Room width.
ft
Floor-to-ceiling height.
ft

Results

Room Volume-ft³
Air Changes per Hour-ACH
Air Turnover Time-min
References: ASHRAE 62.1; ASHRAE Handbook—HVAC Applications; CDC Guidelines for Environmental Infection Control