Sound beacon is a navigation device for blind or visually impaired people. The device emits a periodic sound that allows a person with limited vision to locate the object (for example, entrance to the building). These devices can be attached to doorways of buildings, public transport cabin doors, traffic lights, etc. The system is "last meters solution" and works on audible distances ~5..20m.

Blind people (as any other people), use government buildings, shops, cafes, hospitals, postal offices, transport vehicles etc. Sound beacons greatly simplify navigation for them. The beacon makes your location more accessible. While this itself is a good thing to do, this may also be a requirement in many jurisdictions.

Our beacons are silent, until they need by approaching blind user.
No noise = no complaints from surrounding people.