Seeing is Believing

Oct. 27, 2008
Visual verification bolsters alarm credibility

In most communities when a burglar alarm is activated police are dispatched by a central monitoring station to a specific location to determine the cause of the signal and check on the well-being of occupants. However, because of the fact that many alarms are false (caused by some sort of human error) and police and responding authorities are overloaded and understaffed, some municipalities are experimenting with verified response or non-response if an actual intrusion cannot be verified.

To counterbalance this dangerous policy the security industry developed a widely accepted procedure called Enhanced Call Verification (ECV), which helps reduce false dispatches while still protecting citizens. ECV requires central station personnel to attempt to verify the alarm activation by making a minimum of two phone calls to two different responsible party telephone numbers before dispatching law enforcement to the scene.

The first alarm-verification call foes to the location the alarm originated. If contact with a person is not made a second call is placed to a different number. The secondary number, best practices dictate*, should be to a telephone that is answered even after hours, preferably a cellular phone of a decision maker authorized to request or bypass emergency response.

In-the-field proof that ECV practices are the best solution for false-alarm reduction while maintaining the safety of taxpayers comes from the state of Florida. As of July 1, 2006, the implementation date of the nation’s first statewide ECV law, the Palm Beach County Sheriff’s Department reduced dispatches from 12,712 between October 2005 and December 2005 to 8,802 during the same period in 2006.

Palm Beach County Deputy Charlie Mosher estimated that 80 percent of the department’s dispatch reduction can be attributed to ECV, allowing officers to spend more time in trouble spots and be more proactive on patrol. According to the Alarm Association of Florida other counties in the state have shown a similar reduction in false dispatches as well.

Following the success of Florida’s program, in May 2007 Tennessee passed legislation that requires the practice of ECV throughout the state.

To complement ECV another method the security industry developed to satisfy the requirements of verified response is cross-zoning, first introduced as a software solution for protected premises that consistently requested unwarranted dispatches.

Cross-zoning satisfies the requirements of verified response without endangering civilians who would otherwise have to determine the source of an alarm before police will respond.

To build a cross-zoned alarm system, the designer must define a protection strategy capable of sending at least two separate signals for the protection of one area. The way cross-zoning works is that identifiable signals are generated at the premises to be sent to the central station.

With multiple sensors in place to monitor one area, central-station software analyzes input from various sources to confirm if there is an intruder. If a motion detector trips in one area, the signal is recorded and the central station notifies the subscriber and others who are listed as being responsible for the alarm system. A second alarm signal, received in an adjacent zone in close time proximity (variable based on community), is the confirmation the central station needs to request a dispatch. This builds in increased protection and a fail safe for alarms caused by a door blown open or a bird rattling an exterior window.


One hardware solution to verify the need for law enforcement is impact-activated audio detection that when triggered by glass breaking or other sounds sets off a silent alarm and enables central station operators to “listen in” to sounds at the protected premises.

A second hardware solution incorporates a series of cameras to provide visual verification of the need for emergency dispatch.

Video verification documents a change in local conditions by using cameras to record video signals or image snapshots. The source images can be sent over a communication link, usually an Internet protocol (IP) network, to the central station where monitors retrieve the images through proprietary software. The information is then relayed to law-enforcement and recorded to an event file, which can later be used as prosecution evidence.

An example of how this system works is when a passive infrared or other sensor is triggered a designated number of video frames from before and after the event is sent to the central station.

A second video solution can be incorporated into to a standard panel, which sends the central station an alarm. When a signal is received, a trained monitoring professional accesses the on-site digital video recorder (DVR) through an IP link to determine the cause of the activation. For this type of system, the camera input to the DVR reflects the alarm panel’s zones and partitioning, which allows personnel to look for an alarm source in multiple areas. 


When a business or residence is unattended, central station monitors can “look in” on any camera connected to the system and perform a video guard tour of the area to report exceptional conditions, events or unauthorized entry.

Without a doubt, there are economic benefits of security and IT systems integration, including shared infrastructure. Due to the maturation of alarms-over-Ethernet technology, AHJs across the country are learning that IP-based systems provide secure, redundant and reliable communication.

Sidebar: ANSI/SIA CP-01-2000 Panels

The American National Standards Institute (ANSI), New York and the Security Industry Association (SIA), Alexandria, Va., have created a standard that recommends features for control panels and associated arming and disarming devices to reduce false alarms.

The Control Panel Standard—Features for False Alarm Reduction, ANSI/SIA CP-01-2000, establishes requirements to address false alarms caused by end users, initiating devices and by power failures. It was developed with input from manufacturers, service providers and other industry stakeholders, including Underwriters Laboratories (UL), which lists compliant products and allows these to bear a UL Classification marking. (SIA is currently seeking input for an updated version of the standard,

Understanding that most false alarms occur when there is human interaction with the system, ANSI/SIA CP-01-2000 control panels take aim at user error. This is done by building in extra precautions to minimize unwarranted dispatch of emergency responders.

Modifications include an extension of time for exiting, with 60 seconds as the default and 45 seconds as the minimum. To hasten exiting, a progress annunciation function emits a different sound during the last 10 seconds of delay and the exit time doubles if the user disables the pre-warning feature. Other CP-01 “rules” address failure to exit premises, which results in arming all zones in Stay Mode and a one-time automatic restart of exit delay. However, if there is an exit error, an immediate local alarm will sound. The features are applicable to both residential and commercial properties.

Security installing dealers and integrators should take a leadership position in the fight against false alarms by advocating cross-zoning, ECV and the use of ANSI/SIA CP-01-2000 control panels. The alternative, if local officials believe police are being stretched too thin, is adopting a policy of non-response unless there is confirmation of an emergency. Some major metropolitan areas, including Salt Lake City and Dallas, have resorted to this drastic measure to reduce false alarms. However, after just one year, the Dallas City Council overturned their decision and shelved verified response effective October 1, 2007.

Dallas Mayor Tom Leppert explained his and the council’s position on verified response. “It’s the wrong policy for the pocketbooks of the people of Dallas,” Leppert told the Dallas Morning News. “I think it’s the wrong policy of where we’re going in the future. And I think it’s clearly the wrong message in how we’re talking to our citizens and what the role of the police department is in protecting them.”

Kevin Lehan is the Manager of Public Relations for EMERgency24 and has a decade of experience writing about security systems for the built environment.