Full Product Manual

Useful Equations and Conversions
Area equation for rectangular or square ducts
Area equation for circular ducts
Cubic equations
NOTE: Measurements made in inches
must be converted to feet or meters before using the above formulae.
Width (W)
Height (H)
Area (A) = Width (W) x Height (H)
CFM (ft
3
/min) = Air Velocity (ft/min) x Area (ft
2
)
CMM (m
3
/min) = Air Velocity (m/sec) x Area (m
2
) x 60
Radius
Area (A) =  x r
2
Where = 3.14 and r
2
= radius x
radius