The First Line of Defense
The first line of defense against any intrusion to a facility is the perimeter. Concentric rings of protection comprise the strategy for the design and implementation of an overall security plan. Deciding how to balance perimeter security needs with access needs and to integrate both into the overall security program begins with an overall examination of different perimeters and what technologies exist to protect them. This article will provide guidelines for analyzing and designing more effective perimeter security — from the furthermost edge of the facility down to the core.
Protecting fence or property lines
Fence lines usually run along the outside edge of a facility or property. Technologies that can assist with this part of the security initiative include:
- Fences
From standard chain link to smaller-gauge and unclimbable; fencing is available in a wide range of prices. Razor wire can be added for a relatively small investment.
- Bollards
Available in many shapes, sizes and styles, these range from simple fixed concrete or steel bollards to more complicated hydraulic and electric versions to protect gates and roadways.
- Barriers
An effective deterrent that makes it more difficult for an intruder to get to a particular area, barriers can be as simple as an earthen mound or hill or as elaborate as a steep slope. Concrete walls also form a good barrier.
Fence detection systems
There are a multitude of fence detection systems on the market today; here are just some of them:
- Mechanical or magnetic switch
- Photo electric beam
- Microwave
- Fiber-optic wall
- Audio sensors
- Passive or active ultrasonic
- Passive or active infrared
- Passive IR/ Microwave
- Fence vibration
- Electric field
- Capacitance sensor
- Strain sensitive cable
- Taut wire
- In-ground fiber optic
- Ported coax buried line
- Balance buried pressure
- Buried geophone
- Video motion detection
- Radar
- Acoustic detection
With any of these alternatives, it is always good practice to incorporate two or more technologies to reduce the number of false alarms and for a higher level of protection. For example, a fiber-optic fence system can enhance the potential for intrusion detection and reduce potential false alarms. Buried geophone or in-ground sensors can also be installed within the protected fence area to provide another level of detection and verification. Video motion detection cameras mounted inside or outside a protected fence area will also increase detection potential and verification, and allow security personnel to visually assess any alarm. An additional way to enhance the security of a fiber-optic fence is to mount a volumetric motion detection device such as a microwave or active infrared sensor.
While adding multiple technologies to a perimeter solution will increase the complexity and cost of a security program, the advantages of increased effectiveness and the reduction in false alarm costs can be worth the investment.
Video surveillance and intelligent sensors
Surveillance has changed and new solutions are being integrated into sophisticated video management systems. With Integrated Security Management Systems (ISMS), video can now leap past simple motion detection to the new field of analytics and statistical analysis. These new technologies and integration enable end-users to respond effectively, verify and track possible security violations, thus making security more efficient and effective by responding to real — not false — alarms. There also has been considerable advancement in thermal imaging, which enables the end-user to see in the dark better than ever. Thermal imaging until recently had been limited to high security facilities due to its cost. Today, there are many cost-effective solutions that can meet most security budgets where thermal imaging may be needed.
Simple rules for perimeter security
When planning perimeter security, here are a few rules to guide design and implementation:
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Start with a comprehensive plan that incorporates what violations and intrusions have been experienced and/or that may occur;
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Create a physical barrier or obstacle to reduce the ease of penetration or intrusion through the perimeter;
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Consider integrating two or more technologies to ensure greater protection and reduce costly false alarms;
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Use good video surveillance practices and new technologies; and
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Use an ISMS solution to bring higher levels of response and automation to the perimeter security — resulting in greater overall effectiveness and longer-term cost effectiveness.