False alarm
- For more generic meaning, see False positive.
A false alarm is the phony report of an emergency, causing unnecessary panic and/or bringing resources (such as fire engines) to a place where they are not needed. Over time, repeated false alarms in a certain area will cause its inhabitants to start to ignore all alarms, knowing that each time it will likely be a fake. The concept of this can be traced as far back as the story of The Boy Who Cried Wolf, where many episodes of a boy falsely yelling "wolf" caused the townspeople to ignore his cries when a real wolf came.
In addition, false alarms have the potential of diverting emergency responders away from legitimate emergencies, which could ultimately lead to loss of life. In industrial alarm management, a false alarm could refer either to an alarm with little information content that can usually safely be eliminated, or one that could be valid but is triggered by a faulty instrument. Both types are bad because of the "cry wolf" effect described above.
In (signal) detection theory, a false alarm occurs where a non-target even exceeds the detection criterion and is identified as a target.
One tragic example of the consequences of continued false alarms was at Boland Hall at Seton Hall University on January 19, 2000. Months of false alarms caused many students to start ignoring the fire alarms. However, when an actual fire broke out, three students who ignored the alarms died, and many others suffered injuries.
False alarms could also refer to situations where one becomes startled about something that isn't true.