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Seismic perimeter security

The application of security measures is tailored to the needs and requirements of the facility to be secured. The security approach will be influenced by the type of facility or material to be protected, the nature of the environment, and the client’s previous security experience and any perceived threat. These perceptions form the basis for the user’s initial judgement, however, these perceptions are rarely sufficient to develop an effective security posture.

The nature and tempo of activity in and around the site or facility, the physical configuration of the facility/complex to be secured, the surrounding natural and human environment, along with the fluctuations and variations in the weather, as well as new or proven technologies are all factors which should be considered when planning a security system.

Exterior intrusion detection sensors detect intruders crossing a particular boundary or entering a protected zone. The sensors can be placed in clear zones, e.g. open fields, around buildings or along fence lines. Exterior sensors must be resilient enough not only to withstand outdoor weather conditions, such as extreme heat, cold, dust, rain, sleet and snow, but also reliable enough to detect intrusion during such harsh environmental conditions.

With the advent of modern day electronics, the flexibility to integrate a variety of equipment and capabilities greatly enhances the potential to design an intrusion detection system to meet specific needs. The main elements of an intrusion detection system include: a) the intrusion detection sensor(s), b) the alarm processor, c) the intrusion/alarm monitoring station, and d) the communications structure that connects these elements and connects the system to the reaction elements.

However, all systems also include people and procedures, both of which are of equal and possibly greater importance than the individual technology aspects of the system. In order to effectively use an installed security system, personnel are required to operate, monitor and maintain the system, while an equally professional team is needed to assess and respond to possible intrusions.

In the process of evaluating individual intrusion detection sensors, there are at least three performance characteristics which should be considered: Probability of Detection (PD), False Alarm Rate (FAR), and Vulnerability to Defeat (i.e. typical measures used to defeat or circumvent the sensor).

A major goal of the security planner is to field an integrated intrusion detection system (IDS) which exhibits a low FAR and a high PD and is not susceptible to defeat.

• Probability of Detection provides an indication of sensor performance in detecting movement within a zone covered by the sensor. Probability of detection involves not only the characteristics of the sensor, but also the environment, the method of installation and adjustment, and the assumed behaviour of an intruder.

• False Alarm Rate indicates the expected rate of occurrence of alarms that are not attributable to intrusion activity. ‘False alarms’ and ‘nuisance alarms’ are included under the overall term ‘False Alarm Rate’, although technically there is a distinction between the two terms. A nuisance alarm is an alarm event which the reason is known or suspected (e.g. animal movement/electric disturbance) was probably not caused by an intruder. A false alarm is an alarm when the cause is unknown and an intrusion is therefore possible, but a determination after the fact indicates no intrusion was attempted. However, since the cause of most alarms (both nuisance/false) usually cannot be assessed immediately, all must be responded to as if there is a valid intrusion attempt.

• Vulnerability to Defeat is another measure of the effectiveness of sensors. Since there is presently no single sensor which can reliably detect all intruders, and still have an acceptably low FAR, the potential for “defeat” can be reduced by designing sensor coverage using multiple units of the same sensor, and/or including more than one type of sensor, to provide overlapping of the coverage area and mutual protection for each sensor.

Regardless of how well designed and installed, all intrusion detection systems are vulnerable to power losses, and many do not have an automatic restart capability without human intervention. Potential intruders are aware of this vulnerability and may seek to cut power if they cannot circumvent the system via other means. It is critical that all elements of the system have power backups incorporated into the design and operation to guarantee uninterrupted integrity of the sensor field, alarm reporting, situation assessment, and response force reaction.

SensoGuard

SensoGuard is an Israeli company that develops seismic sensor-based protection systems. The company’s products provide comprehensive protection solutions for a variety of sites. The security systems recognise threats whenever fluctuations are sensed in their vicinity and send an early warning before the intrusion actually occurs. These threats may include footsteps, moving vehicles, digging, use of physical force, drilling, cutting actions and explosions.

SensoGuard’s advantages include:

• Easy to install – plug & play.

• Maintenance free, user friendly.

• Detection and classification - footsteps, vehicle.

• Smart adaptive algorithm.

• Hidden underground.

• Reliable systems – low FAR.

• Ultra low power – works on batteries.

• Automatic restart capability without human intervention.

Watch a Youtube video about the technology at https://www.youtube.com/watch?v=98RiKDEShcE

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