atcomsystems.ca/forum Forums General General Telephone & Systems Information Emergency Elevator phone using cellular communication?

I've not found that to be true except with the cable companies or something like FiOS. Of course there is always the possibility of things going wrong between the terminal and your house with a copper plant. But other than that the chances are, barring a catastrophic failure, of more than one pair developing a problem at a time are mitigated because they don't all travel the same route.

-Hal