OMEGA: “Measuring Air Flow in Ducts, Pipes, Hoods and Stacks”

Simple Guide produced and published by OMEGA.com on techniques for measure airflows in ducts, hoods, stacks etc. It is US published – so units are imperial.
Very useful and straightforward guide for example for choosing to the number of traverse points and their position when monitoring air velocities (using Pitot/Manometer) in ducts.
Copy may be downloaded here:- Airflow Measurement; Omega.com