A very good question.
It is very important to check your Personal Locator Beacon properly. Especially before you head out into a potentially risky situation.
Personal Locator Beacons should never be activated unless you are in grave and eminent danger. So do not push the ON or Emergency Button. Only use the test button.
The reason that you should never activate your PLB, no matter how briefly, is that the emergency signal will be picked up by the Search and Rescue Satellite System. Rescue forces will then attempt to contact you and if they can’t they will come looking for you.
This happens on a daily basis in the United States taking up the time of rescue workers who try to determine if each and every distress signal that comes in id real or not. Don’t contribute to this problem!
406 MHz emergency beacons should only be tested using the “self-test” feature of the beacon or the beacon should be taken to an authorized dealer or test facility. Check the documentation that came with your distress beacon on how to test your specific model correctly.
If you do accidentally activate your beacon you should call the U. S. Air Force Rescue Coordination Center at (800) 851-3051 to advise them that you have set off your PLB accidentally. They will want to know your PLB’s 15 digit Hexidecimal ID (some manufacturers call this the UIN).
A Personal Locator Beacon is a great Safety Device, and should be treated responsibly.
Also be sure to register your Personal Locator Beacon!
This site recommends that you buy a PLB with GPS capability! Don’t try to save a few bucks, you life is worth much more!