false alarm

false alarm

A benign situation initially mistaken for an emergency. Mary thought she was going into labor, but it turned out to be a false alarm. When the smoke detectors started beeping, we thought the building was on fire, but it was just a false alarm caused by faulty wiring.
See also: alarm, false
Farlex Dictionary of Idioms.

false alarm

A warning signal that is groundless, made either by mistake or as a deliberate deception. For example, The rumor that we were all going to get fired was just a false alarm, or Setting off a false alarm is a criminal offense. This expression, first recorded in 1579, today is often used for a report of a nonexistent fire.
See also: alarm, false
The American Heritage® Dictionary of Idioms by Christine Ammer.

a false aˈlarm

a warning of something, especially something unpleasant or dangerous, which does not in fact happen: They thought the packet contained a bomb but it was a false alarm.
See also: alarm, false
Farlex Partner Idioms Dictionary
See also:
  • a false alarm
  • raise the alarm
  • sound the alarm
  • upset
  • I don't want to alarm you, but
  • identity
  • mistaken
  • case of mistaken identity
  • a case of mistaken identity
  • get (one's) head out of the sand
References in periodicals archive
On average, 75% of tornado warnings in the United States are false alarms. The southeastern United States experiences frequent, short-lived tornadoes and the highest tornado fatalities in the nation.
CRY WOLF EFFECT? FALSE ALARMS AND PUBLIC RESPONSES TO TORNADO ALERTS
He was finishing a round of golf in Florida when he was told of Hawaii's false alarm. The president has 46.6 million followers on Twitter, and could have provided quick reassurance to people in Hawaii and on the mainland.
38 minutes of high anxiety
Basketball game interrupted by message urging Hawaii residents to 'seek immediate shelter' during missile threat false alarm
Hawaii residents said 'I love yous' and 'goodbyes' thinking they had just minutes to live after bogus missile warning; The warning turned out to be a terrifying false alarm but for 38 minutes terror reigned and people on the island scrambled for shelter, believing they were about to die
A spokesman for Holyhead Coastguard said the incident was being treated as a "false alarm with good intent".
Rescuers' search over 'false alarm' [...]
"But Kilrush RNLI would rather launch to a false alarm, rather than be called out too late to an emergency situation."
SILLY BILLIES; Bleating goat sparks false alarm sea rescue operation
On 1 June EgyptAir received a false alarm suggesting that there was a bomb on board flight MS960 heading to Bangkok.
EgyptAir flight makes emergency landing in Uzbekistan due to false alarm
"The call-out was a false alarm due to the activation of an intruder alarm.
Worker sets off alarm; NEWS WIRE
This resulted in fire engines being mobilised on blue lights 18,000 times - almost ten a day - to what turned out to be a false alarm.
Alarm over rules on responses to alarms
This resulted in fire engines being mobilised on blue lights 18,000 times -- almost ten a day - to what turned out to be a false alarm.
Changes to Tyne and Wear firefighter alarm call-outs criticised by Fire Brigades Union; Fire Brigades Union believe changes to overnight alarm call-outs due to cuts culture and will increase risk to property
After weeks of testing and thousands of samples, the customer informed us that the QS-B220 had the lowest false alarm rate out of all of the tested systems.
Implant Sciences gets order for 75 detections systems
The new Magic PDM-IXx12/T and PDM-IXx18/T dual motion detectors offer reliable detection of intruders and high false alarm immunity.
Siemens detectors cut false alarms
The official definition of a false alarm is "a fire signal resulting from a cause other than fire".
False alerts cost region's fire service PS2m a year; Hospitals prove worst offenders for call-outs costing PS400 a time
PATIENTS and staff at the Jidhafs Health Centre were yesterday evacuated following a false alarm.
Health centre is evacuated after fire alarm panic
The alert prompted a response from Eastbourne and Hastings inshore RNLI lifeboats at around 8.30am this morning - only for them to find it was a false alarm.
Sea swimmer's partner a seal
"The images from the two cameras [infra-red and RGB] are combined using computer classification software to produce real-time alerts with the lowest possible false alarm rate."
Baggage screening for humans: how can you prevent criminals from beating security channels by sneaking through the baggage system? Tom Allett explains Vanderlande's new heat-sensitive detection system