
CFM Measurements
Measure the area of the duct using the diagrams below for rectangular and circular ducts (If the
duct measurements are made in inches, divide the inches by 144 to get the area in square feet).
Plug the area value (in square feet) in the cubic equations below. Note that the air velocity must be
plugged into the cubic equations also.
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
Warranty
Triplett / Jewell Instruments extends the following warranty to the original purchaser of
these goods for use. Triplett warrants to the original purchaser for use that the products
sold by it will be free from defects in workmanship and material for a period of (1) one
year from the date of purchase. This warranty does not apply to any of our products
which have been repaired or altered by unauthorized persons in any way or purchased
from unauthorized distributors so as, in our sole judgment, to injure their stability or
reliability, or which have been subject to misuse, abuse, misapplication, negligence,
accident or which have had the serial numbers altered, defaced, or removed.
Accessories, including batteries are not covered by this warranty
Copyright © 2021 Triplett
www.triplett.com