audible intruder alarm
audible intruder alarma burglar alarm that makes a noise and is thus subject to special regulation. In particular there is a power of entry to silence the device if the alarm has been sounding continuously for more than twenty minutes or intermittently for more than one hour, the sounding of the alarm is likely to give persons living or working in the vicinity of the premises reasonable cause for annoyance, and, if the premises are in an alarm notification area, reasonable steps have been taken to get the nominated key-holder to silence the alarm.
Collins Dictionary of Law © W.J. Stewart, 2006