Verbal Warning Systems
Another facility offered in conjunction with a CCTV installation, is the ability to give a message, via a loudspeaker, when an intruder sets off a detection sensor. Messages are designed for each location but, if it is in an area where the public should not be, it could be along the lines of "LEAVE NOW! The police have been called and you are being recorded on video".
Research has shown that although people will only obey a written notice to leave in 7% of cases they will obey an audible command 92% of the time.