Line monitors are a handheld instrument that safety professionals use to measure and monitor the sound level generated by a machine, process or other noisy activity in an industrial environment. Often called a db (decibel) meter, they essentially measure noise levels.
Line monitors are used for measuring acoustics (sound waves that travel through air). They are usually hand-held instruments with a microphone. The diaphragm of the microphone responds to changes in air pressure caused by sound waves and displays them on the screen of the monitor.
Line monitors are available in two classes: class one and class two. These monitors function in the same way but vary when it comes to their ability to tolerate errors present in the devices being measured.
Class one line monitors have a broader frequency range that makes them suitable for monitoring high-precision sound measurements (in a scientific laboratory, for example).
Class two line monitors have greater tolerance for noise production and so are suitable for more industrial environments.
Seaward 136A917 Line Monitor 1600Hz