There can hardly be a driver in America who hasn't been cruising down the highway when the regular programming on the radio is interrupted for a test of the Emergency Broadcast System. A brief warning that a test is about to occur is followed by a burst of tones that sounds like it's coming from a dial-up computer modem followed by a reminder that what was just aired was a test.

Or, perhaps you live a tornado-prone section of the country like I do. If so, we probably share this similar experience. Absorbed in the work at hand, you hear a whine in the distance that at first startles you and then makes you look at a clock and a calendar to confirm it's 11 a.m. on the first Tuesday of the month --the time local government authorities test the city's emergency warning sirens. If it isn't, you know your next step is to grab a portable radio and flashlight and head for the basement.

I'm not sure exactly when this loose network of government officials, broadcasters and local sirens coalesced into an organized system for alerting the public of an impending emergency - although it probably was the same time the USA entered into a protracted Cold War with the Soviet Union. However, I am certain the original planners of the system did not envision the existence of thousands of private TV channels and digital signage networks.

Yet, that's exactly where technology has taken us today. The existence of these networks gives corporations, universities, colleges, secondary and even primary educators, government agencies, the military and other institutions the opportunity

to inform people within the reach of their private TV and digital signage networks of an unfolding emergency situation.

I would argue that in some situations the ability of these networks to deliver highly targeted messaging to a select audience makes them even more valuable than a

blaring siren or even a broadcaster. It's a sad fact of life that we live in a time when a lone person or a small group can perpetrate an act of evil so deplorable that tens, hundreds or even thousands of innocent people can come face to face with peril and

possibly death. In those situations, knowing where to go and what to do can mean the difference between life and death.

In a school, at an airport, in a post office, in a hotel, at a shopping mall, around the campus of a large corporation or even the confines of a small business, a digital signage network or private TV network can be used as a closed-circuit Emergency Alert System. "Terror Alert: Evacuate Terminal A," "Emergency: Gunman in North Wing of Building," or "Warning: Fire On Third Floor -Use West Stairway to Evacuate." These are all vital, yet simple messages that these networks of flat panels and TVs can display to stack the odds in favor of saving lives.

Additionally, with the right software, hardware and interface, the media servers used to schedule and playback digital signage networks and private TV channels can be tied directly into the Emergency Alert System (EAS) to playback warnings of larger dangers, like tornados, flash floods and civil emergencies.

In the next couple of columns, I will lay out some of the technical details of setting up a digital signage network or private TV channel to support the EAS system. (Don't worry. You won't need to be an engineer or computer programmer to understand what's required and how to employ it.) I'll also offer a few tips you might find valuable in preparing for emergencies.

Often in our professional lives we get so focused on our core task -be it selling more widgets, posting our school's social activities, class schedules and menus or welcoming visitors to our companies- that it is easy to lose sight of the bigger picture. We are professional communicators first. We have a powerful medium at our disposal, and we can help to make a difference and possibly save lives when an emergency situation presents itself.