Modern Living: The Highway Helpers

While driving south on Interstate 75 in Florida, Mary O'Rourke of Jacksonville Beach, her daughter and grandson suddenly felt dizzy and nauseated. Sighting a sign reading MOTORIST AID CALL BOX, O'Rourke braked to a stop and followed the simple instructions on the box. Then she lost consciousness. Minutes later, a rescue unit arrived and rushed the family to a nearby hospital, where doctors treated them for carbon-monoxide poisoning caused by a faulty muffler.

The O'Rourkes are among the thousands of motorists who credit emergency call boxes with saving their lives on the nation's highways. The devices made their first appearance in Massachusetts...