Add Time To The Security Event Clock

Securing a building’s perimeter with sensors gives staff more time to react if a threat is detected.

By Brad Martin
From the October 2022 Issue

Of all the responsibilities that comprise facility management, physical security often receives little attention—that is, until something bad happens. Threats range from relatively benign, such as trespassing or unauthorized parking, to very serious, such as break-ins and theft, or even worse, physical threats to on-duty staff. Electronic access control systems, working alongside video surveillance, can provide substantial protection. However, when these systems typically alert monitoring staff of a potential threat, the intruder(s) can be at, or even inside, the building—a critical moment at which the security event clock starts ticking, and there is little time for a proactive response.

But what if we extend the secure area out to the perimeter or even beyond? Detection at the perimeter provides the additional time needed to deploy active deterrents like reactive security lighting or outdoor loudspeakers, as well as greatly enhancing assessment and response capabilities by tracking intruders before they reach the buildings.

Security Starts At The Perimeter

Traditionally, facility security consists of fences, surveillance cameras, access control, and on-site personnel. These measures provide a solid foundation, but security gaps exist—a fence by itself only keeps out opportunistic intruders, cameras record incidents but don’t stop them, and security personnel need to be deployed strategically at larger facilities. Physical security technologies can augment the effectiveness of both physical infrastructure and security personnel. When designed and deployed correctly, it is a cost-effective element of a facility’s risk-management program.

Security Event Clock
Fence-mounted sensors can turn existing fences into smart fences. (Photo: Senstar)

Perimeter intrusion detection systems form the first line of defense, detecting intruders before they get inside. There are many types of technologies, each with their unique strengths. When looking at different systems, consider these factors:

  • Coverage—Does the system protect the entire perimeter (e.g. no blind spots)?
  • Probability of detection—Does the system quickly and accurately detect attempts to breach the perimeter each and every time?
  • Nuisance alarm rate—Does the system only generate alarms for real (or simulated) intrusion attempts? Too many false or nuisance alarms may lead to alarm fatigue and complacency.
  • Ease of installation and maintenance—How easy is the system to install and maintain over its lifespan? Does the manufacturer provide comprehensive service and support plans?
  • Integration with Security and Video Management Systems (SMS/VMS)—Can intrusion events be presented in a way that improves situational awareness? For example:
    • Can the security system display intrusion location alongside access control alarms and other security events?
    • Can the alarms be integrated with video surveillance for automated camera callup?
    • Is there full logging of activity so that incident reports can be generated?

Perimeter Security Options

Fence-mounted sensors (accelerometer-based, fiber optic, or cabled RF) are popular because they offer a cost-effective solution. Simply put, they turn existing fences into smart fences by detecting and locating attempts to cut, climb, or lift the fence fabric. They are field-proven, difficult to defeat, and work reliably in rain, snow, and wind. Generated alarms (which typically include the intrusion zone or precise location) can be used to trigger on-site security resources, including automated camera call-up and deterrence devices like sirens, loudspeakers, or security lights.

Fence-mounted sensors turn an existing fence into a smart fence, detecting locating intrusions at the perimeter, before the intruders reach a sensitive area or building.   

Now, there are several new trends in perimeter security. One is intelligent, low-voltage lighting, which can be installed on the fence. LED-based luminaires provide uniform, wide-spectrum illumination targeted along the fence line. This improves the quality of video feeds by avoiding hot spots, while LED-based lighting reduces electrical and maintenance costs. The “intelligent” component comes from sensors embedded in the luminaires that detect intrusion attempts. In addition to notifying the site’s security system, the luminaires in the immediate area can instantly switch to full power or strobe. Knowing they are detected, potential intruders may rethink their actions.

Another trend is the advances in AI computer vision research that have led to the development of sophisticated video analytics software optimized for outdoor/indoor people tracking, left/removed object detection, PTZ auto-tracking, face and license plate recognition, crowd detection, and more. These software modules may be included as part of video surveillance software or embedded into individual cameras or dedicated appliances.

Video analytics can alert staff of people and vehicle activity, ensuring that suspicious activity both outside and inside a facility is monitored.

Sensor Fusion: The Next Step Forward

A challenge that facility managers must address when deploying security solutions is balancing detection ability with nuisance alarm generation. To ensure sites are protected against stealthy or sophisticated attacks, sensors and analytics are often tuned to quickly generate alarms under the widest range of circumstances. This approach, however, can lead to an increase in nuisance alarms, especially during extreme weather events or in high-activity areas. Advances in signal processing and AI classification technologies can help significantly, but for high-security sites, the added cost and time for performing a proper assessment and response means that any nuisance alarm is one too many.

True sensor fusion is a unique technology that can defeat nuisance alarms once and for all. Simply put, sensor fusion synthesizes data from multiple systems to generate actionable information. More than a simple Boolean logic integration, a sensor fusion engine accesses low-level data from fence sensors and video analytics to intelligently characterize potential risks. Data synthesis enables the system to achieve levels of performance that exceed those of the individual sensors, ensuring that real intrusions are correctly detected while nuisance alarms generated by weather, non-threat activity, and even animals are avoided.

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Sensor fusion can defeat nuisance alarms once and for all by using low-level data from multiple sensors and video analytics to better characterize potential security threats.

Situational Awareness Enables A Faster Response

Adding intelligence to the perimeter provides the starting point for a faster response. But an effective solution does not stop at sensors. The data from the sensors needs to be presented as actionable information, so that monitoring personnel can minimize the time between detection, assessment, and response.

Regardless of the event’s severity, the overall process remains the same: reliable, early detection at the perimeter adds time to the security event clock. During this critical period, intruders can be dissuaded or slowed down by on-site deterrence mechanisms, while operators maintain situational awareness of the entire facility.

Security Event ClockMartin is the Director of Product Management for Senstar. He has also worked as an FPGA developer, Software QA Team Lead and Program Manager. Brad holds a degree in Electrical Engineering (B.Eng) from Lakehead University and a Masters of Business Administration (MBA) from Wilfrid Laurier University.

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Check out more technology and facility management news in previous Facility Executive Tech & FM Columns.