The S-111 staff station includes an on/off tone switch that can be passed, green LED to indicate normal call, and red LED to indicate emergency call. It is also furnished with a pull-string to place a call on the system. S-111 has a tone on-off switch that is provided to silence the audible alert by staff. Normal calls are indicated with a steady green LED and slow intermittent tone. Emergency calls are indicated with flashing red LED and rapid tone.