The two-way voice communication device inside an elevator car connected to a permanently attended monitoring centre, enabling trapped passengers to call for help and receive a response at any time.
Full Definition
EN 81-20 requires every elevator to be equipped with a means of two-way communication between the car and a permanently attended rescue service — not merely a building reception or a voicemail system. The alarm signal must be capable of being raised by the passenger without knowledge of the car's position (a simple push-button); the communication link must be able to summon help; and the rescue service must be able to speak back to the car. EN 81-28 (Remote Alarm on Passenger and Goods Passenger Lifts) extends this by standardising the remote alarm protocol, message format, and connection to a monitoring centre. Requirements under EN 81-28: the alarm must be transmitted even if the normal telephone line fails (dual-path transmission — GSM/GPRS and PSTN); the monitoring centre must acknowledge within 60 seconds; and the centre must be able to initiate a two-way voice call to the car. In accessible lifts (EN 81-70), a visual acknowledgement indicator (typically a flashing green light or display) must confirm that the alarm call has been received, for the benefit of deaf or hard-of-hearing passengers. The emergency call button must be yellow, identified by a bell symbol, and illuminated.
