ABSTRACT
In many buildings, it is necessary to have a system of calling staff who are on duty in an office or staff room to go to rooms elsewhere in the building. This happens, for example, in hotels, hospitals and retirement homes. In the case of hospitals, patients wish to call a nurse who is in the ward office to their own beds, and in hotels guests may wish to call staff to their rooms. In retirement homes, a resident may wish to summon either domestic or nursing staff. All such systems can be arranged electrically and form part of the electrical services in a building.
