Reference

Worked drum fan CFM examples

Room volume and ACH cases with expected 20 / 24 / 30 in classes and NO_MATCH.

≈667 CFM → 20 in class (lnk_class_20).

Details

Volume 5,000; 5000×8/60≈667; ≤4800 → 20 in.

Tools

≈4,200 CFM → 20 in class (lnk_class_20).

Details

Volume 16,800; 16800×15/60=4200; ≤4800 → 20 in.

Tools

≈5,600 CFM → 24 in class (lnk_class_24).

Details

Volume 28,000; 28000×12/60=5600; >4800; ≤7500 → 24 in.

Tools

≈9,600 CFM → 30 in class (lnk_class_30).

Details

Volume 48,000; 48000×12/60=9600; >7500; ≤12000 → 30 in.

Reference

≈24,000 CFM → NO_MATCH.

Details

Volume 96,000; 96000×15/60=24000 exceeds 12,000.

Guides

Volume, ACH, and grill safety explained.