India, May 11 -- Last calls for boarding and lost-item announcements aren't the only things to listen for over an airport's loudspeakers. The facility-wide paging systems can also be used for critical, time-sensitive alerts when acting fast could potentially save a life. Knowing what to do when you hear one can make a difference to the situation's outcome-and help keep you and those around you calm while the scenario unfolds.

One such announcement you may hear in an airport is a Code Adam, a protocol employed when a child is reported missing. "Code Adam is designed to locate missing children quickly with an immediate and coordinated search, often resolved within minutes," says John Bischoff, vice president of the Missing Children Divisi...