As Americans, we are becoming more and more dependent on our cell phones. Many of us never leave home without them. There are two places, however, that require that we shut them off-at a hospital and on an airplane. As annoying as this policy might be to some people, once they understand the reasons behind these bans it is actually a reasonable request.

Most people have experienced talking on a cordless phone and suddenly picking up a conversation from another phone or even a truck driver talking on his CB. Or you may be dialing number on your cell phone number only to hear it coming through your radio. These situations are caused by the fact that all transmitting equipment can transmit lower power signals on harmonic side bands at close range. Even if your cell phone is not in use, as long as it is turned on the phone will continuously send and receive signals to and from the cell tower to maintain the connection between the two. While this form of interference between transmitters in your home is annoying, the situation takes on a more serious role in hospitals and on airplanes.

In our society of modern technology, airplanes have become more advanced as the years have gone by. There are numerous radios in the cockpit that allow the pilot to talk to the air tower. He can also talk to the tower where the airplane is going to land. During the flight, these aviators are in constant contact with air traffic controllers, who map the flight paths for hundreds of planes that are in the sky at the same time. The pilots also use their own radar systems in case there are any obstacles that the controllers may have missed. Another feature of today's aircraft is computers that alert the cockpit to any malfunctions within the plane itself. With all this communication going on, just imagine how dangerous the situation could become if any interference garbled any one of these channels of communication. This is the reason that upon boarding an airplane, the airlines ask that you shut off your cell phone, obviously for good reason.

The problem with cell phone usage in a hospital setting is similar to that of an airplane. Many pieces of hospital equipment such as vital statistics monitors are wireless and send signals from the equipment in the patient's room to a monitor at the nurse's station. If a patient's blood pressure or heart rate rises or falls to dangerous levels, the nurses are alerted immediately and can take the appropriate measures. Any interference with these signals could lead to a patient's death without the nurses even being aware that anything was wrong. Interference from cell phones can also disrupt communication between hospitals and emergency vehicles, such as ambulances and rescue helicopters.

So the next time you start to get upset when you are asked to turn your cell phone off at a hospital or on an airplane, keep in mind the possible consequences if you do not. It is well worth a few missed phone calls.