How can this be tested?
Jingling keys, dog barks, screaming, dishes/glasses in the sink?
Try a cheap piece of glass( $1 glass plates and cups can be obtained at dollar stores), and actually break it near window/door in a box with say a hammer to simulate a break in /glass shatter.
Or obtain a glass break tester: https://www.google.com/search?q=glass+break+tester&ie=&oe=
Hmmm - I tried some of that and it doesn’t activate unless I’m very close to it, and it’s on the most sensitive setting.
Well, glass breaks really are not all that dependable. Shock sensors are what you really want. Also make sure you don’t have heavy curtains on Glass door/windows (heavy curtains will render the GB’s near useless).
Glass breaks can be defeated with a $5 roll of duct tape (tape glass door/window with duct tape than break it)
My recommendation is to go with an Image Sensor which can be configured to capture motion events without activating alarms, for example if you have pets. GB’s are meant as a third line of defense after perimeter and interior motions, not as a primary.
Jingling car keys is a good test but it usually only works at a short distance. It also helps to clap your hands just before jingling the keys to simulate the initial thump before the shattering of glass.
Aside from actually breaking a window, the best way to test is with a glass break sound generator.
This is what professional installers use to test at realistic distances.