What Happens When a 911 Emergency Call Goes Silent?

Open-line calls have long plagued emergency dispatchers, who handle about 240 million calls in more than 6,000 communications centers across the country, according to Trey Forgety, government affairs director for the National Emergency Number Association, a trade group.

The advent of cellular technology has only expanded the potential for confusion. To those on the receiving end of the line, the silence can signify a prank, a pocket-dial or, just as easily, something haunting. Even in the land-line age, open-line calls provided a singular vexation. Modern dispatchers work under banks of video screens, answering calls with a mouse click, speaking into headsets and monitoring digital mapping programs. About 70 percent of their calls come from cellular phones, which tend to provide only a vague indication of the caller’s whereabouts, according to the Federal Communications Commission.