An alarm gives an audible or visual warning about a problem or condition.Alarms include:
burglar alarms, designed to warn of burglaries; this is often a silent alarm: the police or guards are warned without indication to the burglar, which increases the chances of catching him or her.
alarm clocks can produce an alarm at a given time
distributed control manufacturing system or DCSs, found in nuclear power plants, refineries and chemical facilities also generate alarms to direct the operator's attention to an important event that he or she needs to address.
alarms in an operation and maintenance (O&M) monitoring system, which informs the bad working state of (a particular part of) the system under monitoring.
safety alarms, which go off if a dangerous condition occurs. Common public safety alarms include:
tornado sirens
fire alarms
"Multiple-alarm fire", a locally-specific measure of the severity of a fire and the fire-department reaction required.
car alarms
community