Since 1921 the American Society of Mechanical Engineers (ASME) have issued the A17.1 Safety Code for Elevators and Escalators; the definitive safety code for elevators in the USA and Canada (since being harmonized with CSA B44 in 2000).
A17.1 is typically updated every two to three years to ensure the latest safety requirements are captured; 2009 saw a major change to SECTION 2.27 EMERGENCY OPERATION AND SIGNALING DEVICES, with the introduction of a clause requiring verification of the means of communication used to connect the elevator emergency telephone to the outside world. This is typically referred to as ‘line monitoring’. The 2009 Addendum should be used to replace the pages in the 2007 edition of A17.1
Always check with your local Authority Having Jurisdiction (AHJ) for current Code enforcement and specific interpretations in your state and local area.
The line monitoring requirement was introduced following reports of trapped passengers being unable to call for help due to “communication failures”. When these incidents were investigated it was found that the most commonly cited causes of failure were disconnected phone lines and changes to dialing plans (e.g. “Dial 1 for an outside line…”, etc.) and not a failure of the equipment itself.
Regular manual testing of the elevator emergency telephone is widely acknowledged as the best method to establish if the system is in working order. However, it’s not practical to have a building employee regularly and manually test each emergency telephone in most buildings. Therefore A17.1 requires an automatic test of the means of communication at least daily.
The reason ‘means of communication’ is used as opposed to ‘telephone line’ is that the code acknowledges that other means such as cellular gateways and Voice of Internet Protocol (VoIP) systems can be used to connect emergency telephones.
The automatic test must verify if the communication means is operable and, in the event of a failure occurring, trigger an alert in the building; the alert has both an audible and visual component.
Testing is done in a variety of ways. When connecting to analog telephone lines, detecting a loss of line voltage is often used to indicate a failure. Cellular gateways can be designed to generate line voltages and/or analog dial tones and, in the event of cell signal falling below the point at which a call can be place, to cut these signals. VoIP systems can also be setup to provide a communication failure signal in the event of a network failure.
The visual component (often a red LED) of the alert will illuminate intermittently until the communication means is restored. The audible component sounds every 30 seconds until the communication means is restored or it is silenced by authorized personnel. To ensure only authorized personnel can silence the alert a key is typically required to operate the silence function. If the means of communication is not restored by the time the next automatic test is performed the audible alert is reactivated.
Code requires that the visual and audible alert be installed in the vicinity of the fire recall switch and visible to elevator users. A label reading “ELEVATOR COMMUCNAITON FAILURE” in 0.25in (5mm) tall letters is also required. The minimum requirement is for one visual and audible alert per group of elevators controlled by the fire recall switch.
Janus Elevator provides a wide range of A17.1, ADA and A117.1 code compliant elevator emergency telephones and accessories including Line Monitoring Units.