GSO ISO 14511:2021
Measurement of fluid flow in closed conduits — Thermal mass flowmeters
This document gives guidelines for the specification, testing, inspection, installation, operation and calibration of thermal mass gas flowmeters for the metering of gases and gas mixtures. It is not applicable to measuring liquid mass flowrates using thermal mass flowmeters.
This document is not applicable to hot wire and other hot film anemometers, also used in making point velocity measurements.