Page 69 - Security Today, July/August 2020
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“Designing an effective access control system means bringing together numerous systems that are engineered to work together as a cohesive unit.”
add-ons to address some of these weaknesses, such as barbed or razor wire along the top of the fence to reduce the likelihood of somebody scaling the boundary. But unfortunately, this doesn’t do much to improve the aesthetics of the fence and may actually discourage customers from wanting to enter. A better option for a security fence is something both more attractive and heavy duty.
CHOOSING THE RIGHT FENCING SOLUTION
For data facilities that are looking to protect the occupants and contents, a fence that is classified as a high-security is a better option than the commonly seen razor wire-lined chain link fence. Several factors differentiate a standard fence from a high-security fence: the materials it is made from, the way those materials are as- sembled and the specific design features it offers.
For a fence to be considered a high-security option, the mate- rial that the primary components are manufactured from should be high-strength metals such as steel. Steel panels have several notice- able distinctions from the aluminum or wrought fencing commonly seen around homes or apartments.
They are heavier weight and generally have the vertical and horizontal components integrated, instead of individually attached pickets seen in a wrought iron fence. Since each panel is built from steel and attached to the rest of the fence, it is more difficult to cut or remove sections of the fence.
In addition, high-security fences are composed of pales rather than standard pickets. A pale is a roll-formed steel shape that is larger in size and gauge of steel, which creates a visual deterrence, as well as presents significant difficulties in cutting or accessing the property. Pales are typically spaced at 3 inches or 1 7/8 inches, along a C-channel rail. Pales also generally extend all the way to the ground, which adds structural stability and makes it more difficult for an intruder to crawl underneath. The rail is a second key com- ponent in a high security fence as its design is intended to not only withstand severe mid-span downforce but also to prevent climbing.
ANTI-CLIMB AND ANTI-FORCE
The materials and manufacturing process combine to give high- security fences anti-climb capabilities and the ability to integrate reinforcements.
Anti-climb is a function of two separate components: the shape of the rail and the spacing of the pales. The C-channel rail has a se- verely sloped upper side that is intended to inhibit a foot from fitting on top of the rail, which discourages climbing of the fence panel. Fences that are anti-climb are generally taller than normal fences — often more than eight feet tall. Additionally, the tops of the fences are curved, split or spear-shaped, which further discourages trespass- ers. Furthermore, the pales are spaced closer together with higher rails, which keeps the horizontal rails from being used as leverage.
This combination of tighter spacing of the pales, strong C-channel rails and high-strength steel also make it so that these fences can han- dle the weight of multiple people trying to breach them. But should a security fence need additional strength, builders can utilize a number of methods to reinforce the anchor points of a fence during installa- tion. The Whole Building Design Guide specifies several methods for
utilizing cement to secure the vertical pieces during installation. Additionally, reinforcement methods such as a concrete dead- man at strategic points and corners offer more integrated strength.
Designers can also add a secondary fence for additional security.
BUILDING THE REST OF THE ACCESS PUZZLE
When designing an access control system, the points of entry are a key component of the fence’s design and how it is installed. Designers should take into account the number of cycles of people and/or vehicles that will pass through a gate when deciding the best method for access control at a facility’s gates or entry points. Whether it’s cantilevered gates, bollards or crash barriers, numerous systems that are effective at controlling access and integrate into the broader design are available.
Many high-security fences have features engineered into their design that enable the integration of other security systems such as video monitoring, motion detection or badge scanners.
Some fencing manufacturers are able to add to increased security measures by building cable runs into the channels of the rails and pales so that cameras, badge scanner pads or RFID monitors can be installed. Physical cables can also be added on the back side of a high-security fence to harden the perimeter and add crash protection. Those cables are typically attached to the back rail through threaded inserts and placed inside the rails on the interior side of the fencing.
Other design best practices can be used to increase the security performance and access control abilities of a high-security fence. Crime Prevention Through Environmental Design (CPTED) incor- porates fencing and other building and environmental elements as part of their methods of reducing the chances of crime occurring.
According to CPTED best practices, building designers should avoid chain link fencing and razor-wire fence topping, as it com- municates the absence of a physical presence and a reduced risk of being detected. Steel and aluminum security fencing easily inte- grates into most landscapes and can support the addition of other elements such as shrubbery as well, making it an ideal solution for these crucial areas.
Designing an effective access control system means bringing to- gether numerous systems that are engineered to work together as a cohesive unit. But it starts at the fence line. Utilizing a steel fence that incorporates anti-climb and other access control
features will help to create a safe and secure space for your employees and your data. Are your physi- cal access control systems built to withstand the threats?
Toby Bostwick is the vice president of product and brand at Fortress Building Products.
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