Car appointments
Car and landing controls illuminate when the desired floor button is pressed. A battery-operated emergency light and alarm are standard features.
[http://www.accessind.com/flexilift.html]

Public Building Package (emergency stop switch, alarm and battery powered emergency lighting

Battery Backup Emergency Light : In the event of a power
failure, the inside of the elevator is illuminated by a battery powered light
[www.accessind.com/docs/ downloadmanuals/om.flexi-lift.pdf]


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Note added at 4 hrs 53 mins (2004-07-30 13:56:19 GMT)
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An intercom would not normally need its own power supply. Like telephones, they are powered by some ethereal substance that just whizzes down the lines, between telephone poles, and has no visible origin ;-)

However, it might so happen that ALL the wires between the lift car and the outside are severed, in which case some sort of \"mobile intercom\" might be useful. However, an audible alarm would serve the same purpose of establishing contact and would also enable people outside to locate the lift, wherever it might be (if all cables are severed, there would be no indication of which floor(s) it was on or between). Having established its position, people could then talk to the trapped people from nearby.

Question: What is the minimum decibel level that should be generated by the audible signaling device as measured from outside the hoistway with the doors closed?
A17.1, A17.2 or ASME interpretations are silent on how the sound level is to be determined and the test procedure to be employed. The code only requires that audible signaling devices have a sound pressure rating of not less than 80-db and not more than 90-db as measured at a distance of 10-ft. (3050-mm). The rule states that
the device must be audible in the car and outside the hoistway, but gives no specific sound levels for these locations. It is not clear as to where, and under what conditions the sound level is to be verified.
The intent of the alarm device is to call attention to an emergency involving the elevator. It is reasonable to presume that the sound level outside the hoistway should be loud enough to attract attention. In most cases, the alarm button will be activated when the elevator doors are closed. Many variables will account for how effective an alarm is based on the operating environment for the elevator. Thus, the alarm’s effectiveness lies in the inspectors’
judgement and will be based on the operating environment. In extreme cases, it may be necessary to provide a supplemental audible or visual device to call attention to the elevator alarm.
[www.cbs.state.or.us/external/bcd/ tag/interp/audible_signaling_device2000_007.pdf]