Keep them out, and better yet, keep them from even considering trying to get in. And if they try, make them take enough time for you to respond.
A simple enough concept, and in industries dealing specifically with security, these thoughts are reflected in the three “Ds:” Deter, Detect, and Delay.
Terrorist plots against high-risk targets – such as government facilities, power plants, and transportation nodes – underscore the importance of perimeter control to prevent or mitigate unauthorized parties from breaching the perimeter of a wide range of facilities, from commercial properties to critical infrastructures.
Thousands of chemical and petrochemical facilities are subject to U.S. Department of Homeland Security (DHS) regulation under the Chemical Facility Anti-Terrorism Standards (CFATS). Certain industrial facilities that ship or receive particular classes and quantities of hazardous materials by rail are also facing new security requirements for freight rail security implemented by the Transportation Security Administration, another component of DHS.
Industrial Security Fencing
For example, a chemical facility that ships chlorine or anhydrous ammonia must take specific steps to ensure the chain of custody and control between the facility (as shipper) and the railroad (as carrier). Keeping rail cars containing certain hazardous materials in a so called “rail secure area” is one requirement of the regulations. Of course, many facilities will use industrial security fencing to demark and protect their “rail secure areas.”
Addressing the threats to all types of facilities, fencing, the core element of perimeter control, has evolved to address the challenges of perceived and real needs, reflecting improvements in strength, modularity, and aesthetics. These developments have resulted in systems far superior to previously held standards, providing solutions for commercial, industrial, governmental, and ultra-high security applications.
Additionally, there is a greater recognition of fencing as a central aspect of a “system of systems,” requiring integration with complementary security measures, such as tamper detection, surveillance, and lighting.
Mesh Panel Fencing
In particular, security mesh panel fencing has emerged as the material of choice among many security experts, architects, and installation contractors because it offers unparalleled anti-cut, anti-climb strength and security as well as availability, affordability, and diverse architectural qualities across a range of mesh material options.
Fencing constructed with anti-cut, anti-climb security mesh panels have gained popularity in the U.S. – after years of being the standard in Europe and other parts of the world – because they incorporate small openings that prevent a would-be intruder from effectively gaining a hand or foot hold with which to climb. Small mesh openings also resist cutting tools – and the substantial thickness of most mesh resists all but the most substantial cutting tools.
Field tests have demonstrated the strength of rigid metal mesh against cutting attacks. When common tools such as a wire cutter, bolt cutter, axe, or crowbar were applied, the mesh demonstrated a substantial delay in penetration; in some cases, entirely resisting the creation of a useable gap. Tests showed that a double-layer welded wire mesh offers the most protection – preventing the formation of a gap large enough to insert cutters and withstanding prying attempts with a crowbar.
Aesthetic goals can be achieved by powder coating the fence barrier, including posts, rails, and fixtures. Advances in powder coat materials protect the barrier from sun (U.V. rays are especially damaging to many low-grade paints and coatings), wind, and moisture. This, in turn, increases the service life of the fence while maintaining its visual appeal for many years.
Recent developments in the construction of anti-cut, anti-climb mesh fencing – utilizing horizontal railing running continuously along the entirety of the fence line to support the mesh – allow the seamless integration of surveillance, tamper detection cabling, lighting, even communications.
The result is a anti-cut, anti-climb mesh “smart fence” that offers not merely a barrier but the framework upon which to build the overall site security plan reflecting all three ‘Ds’ of security (i.e. Deterrence, Detection, and Delay).
Importantly, this smart fence can be created without the added expense of trenching and intrusion detection cabling is protected from weather, vandalism, and tampering because it is contained within the fence’s rails. This type of integration is uncommon in chain link, ornamental, and palisade-style fencing because any horizontal members within the fence framework typically terminate at each post point.
This same development in fence technology – employing a system of horizontal rails within the framework of the barrier itself – also enables easy and affordable retrofitting of chain link fencing without removing the existing posts. The result is a more secure barrier at a cost that is lower than a complete replacement of the existing posts.
The Three ‘Ds’
Whether a fence, gate, or partition, a security barrier must achieve security’s three “Ds”:
Deter: Preventing an attack from occurring, or diverting it to a more appealing target, is the most effective perimeter security tool, and for effective deterrence, size matters. The fence must eliminate attack by presenting a formidable-looking obstacle that discourages attempts to penetrate or circumvent the barrier, which is usually achieved through barrier height, barrier weight, complementary barrier technology (e.g., tamper detection) and security enhancements (e.g., barbed tape concertina). Deterrence can be achieved in various ways, and does not exclude maintaining a visually appealing barrier appropriate to the architecture of the facility.
Detection: Should someone attempt to breach the barrier – over it, through it, or below it – knowing that an attack is occurring in real time is critical for mitigation and response. Ideally, detection will include information regarding when, where, and with what force an attack is happening. Indeed, the physical security barrier should be considered a fully integrated component that works in concert with an overall site security plan and include tamper detection, surveillance, and lighting.
However, even simple steps, such as maintaining visibility, add substantially to detection capabilities. Hedges and other landscape greenery may be attractive along a fence-line, but offer blind spots for attackers to breach a barrier unseen or, alternatively, hide and conduct surveillance.
Delay: A tall and heavy barrier – such as anti-climb, anti-cut rigid mesh fencing – will hinder penetration attempts and increase the probability of detection and response by security personnel or law enforcement. Similarly, heavy rail vehicular-resistant fencing and gates can defeat or substantially delay an attack, allowing time for response.
In the case of anti-climbing resistance, barrier height has a direct and measurable effect on delay; doubling the fence height increases climbing time by a factor of 10. So, if it takes 10 seconds to scale a 10-foot fence, it will take around a minute-and-a-half to scale a 20-foot fence.
With respect to anti-cutting resistance, the weight, the type and the general design of the barrier material all impact delay time. Some materials may be heavy, but can be relatively easy to disassemble, such as many offerings of chain link material.
Taking the Next Step
Once the threat to a facility is defined and barrier types analyzed and ranked, the next step often involves consulting a firm experienced in designing security barriers. Qualified fence manufacturers can engineer a solution to fit an application’s requirements while assisting in the development of a barrier specification that adheres to performance standards specific to geographic, environmental, and government-mandated security regulations.
Performance standards are critical. Ultimately, a facility’s security is measured against the ability to meet or exceed performance standards and protect the asset (e.g., U.S. Department of Homeland Security regulation under the Chemical Facility Anti-Terrorism Standards [CFATS]). Security standards for barriers are only one of many considerations, but appropriate fencing is critical – the success or failure of a site’s overall security plan often begins or ends at the perimeter line.
John F. Payne, president of Payne Fence Products, LLC (a member of the Betafence group), has overseen the development of revolutionary fence and barrier systems, five of which are currently pending U.S. and/or international patents. He has been active through ASTM International in developing physical barrier industry standards for homeland security, impact testing, and architectural metal fence. Payne has worked with U.S. Customs and Border Protection (CBP) and the U.S. Army Corps of Engineers (USACE), to develop physical security solutions for the country’s southern border and U.S. Department of Homeland Security (DHS) detention centers.
Steven E. Roberts began working in the area of critical infrastructure protection in 1999 and now is an attorney practising homeland security law and regulation. He is a columnist for the National Law Journal and Chemical Week, and is a regular guest instructor at the U.S. DHS’s Federal Law Enforcement Training Center (FLETC) in Glynco, Georgia. Roberts is also a lecturer at the University of Houston Law School.