Every fume hood on campus is equipped with a flow meter and/or controller, which can help determine if the fume hood is operating properly or if it may need service. A flow meter is a device that measures actual air flow in the hood, whereas a flow controller is able to manipulate a valve to alter flow. Some hoods are also equipped with sash sensors which can change air flow based on sash height to maintain proper face velocity. If your flow meter is not working properly, please put in a work request through the physical plant here and then report the issue to EH&S at email@example.com. This guide will walk through some of the types of meters that may be encountered on the hoods on campus. There are many different types on campus, and if there are ever any questions about specifics not covered in this guide, please contact EH&S.