Proliferation of new technologies like Voice over Internet Protocol making it difficult for emergency dispatchers to find callers.
They can't send you help if they can't find you. That's the problem confronting 911 dispatchers across the country.
In some densely populated areas like California's Silicon Valley, a 911 call from a cellphone may be routed to one of several potential recipients. Each time a call gets rerouted delays the time emergency aid can be dispatched.
VoIP users may wish to verify with their provider that a 911 call will even make it to a dispatcher. Many VoIP providers have not yet been able to provide access to the 911 phone networks.
The state of Texas sued Vonage over this issue, after a Houston teenager tried to call 911 for help during a home invasion and instead got a message saying 911 wasn't available.
New cellphone features like Enhanced 911 have been coming to market. E911 helps route a call to the right place by virtue of having a global positioning chip in the handset. Other E911 phones tell the dispatch center which cell tower handled an incoming call.