##### Asked by: Fousseni Tudo

asked in category: General Last Updated: 12th March, 2020# How do you measure CFM with an anemometer?

**anemometer**, a test instrument that

**measures**air velocity is used to determine the average air speed in the duct. Then the average feet per minute is multiplied by the area of the duct in square feet to determine the airflow moving through the duct.

Click to see full answer.

Similarly one may ask, how do you use a CFM meter?

Press the UNITS button to select the desired air flow units: CMM (cubic **meters** per minute) or **CFM** (cubic feet per minute). NOTE: At power up the **meter** will display the last unit of measure previously entered. 3. To begin entering the area in m2 or ft2, press and hold the AREA button until it beeps twice.

Also Know, what is the formula of CFM? **CFM** = FPM x Duct Cross Sectional Area Finding the Flow Velocity, typically expressed in feet per minute (FPM), is the first step in filling in our **equation** variables. To find the Flow Velocity, we use the **equation**: FPM = 4005 x √ΔP (The square root of the Velocity Pressure).

Accordingly, how do I know the CFM of my exhaust fan?

You **measure** the velocity at a points in the duct and find the average velocity in the **exhaust** duct is 400 FPM. Multiply 400 Feet per Minute times the area of the duct, which is . 35 square feet, to find 140 **CFM exhaust fan** airflow.

How many CFM can a 6 duct handle?

100 cfm