Air Velocity Calculator (FPM)

Air velocity measures how fast air moves through an industrial duct system, measured in feet per minute (FPM). Maintaining the proper conveying velocity is critical for industrial dust collection. If air moves too slowly, heavy dust drops out of the airstream and clogs your ductwork. If air moves too fast, you waste fan horsepower, generate excess noise, and accelerate pipe wear.

Air Velocity (FPM) = Airflow Volume (CFM) ÷ Duct Cross-Sectional Area (sq. ft.)

• Light dust and fumes (welding, smoke): 2,000 to 2,500 FPM
• Medium industrial dust (sawdust, plastic, grain): 3,500 to 4,000 FPM
• Heavy dust and abrasives (metal grinding, sand, lead): 4,000 to 4,500 FPM