What is AT/FP Fence? And Related Perimeter Security?

Posted by Dawn Lowndes on Sun, Dec 05, 2010

In Fence Design, Perimeter Security, ATFP, Gates, Specifications, Military Fence, Government Fence

ATFP FENCEAnti-Terrorism/Force Protection (ATFP) is generally defined as a federal security program formed to protect personnel, information, and critical resources from outside attacks.  These attacks could be attempted by the use of Rocket Propelled Grenades (RPG), truck bombs, or any means of weighted attack force. Areas of planned security could include law enforcement personnel, intelligence and training. For our purposes we will only discuss the physical security of a site. 

The standards set by the federal government can be used to protect areas such as military vicinity, state and local courthouses, banking centers and certain corporate areas. Corporations can deal with very security sensitive matters like financial markets and Internet service providing computer farms.

ATFP secured structures can actually be made better able to prevent blasts from having a great effect. This can be done by ‘hardening’ the exterior of the structure by blast proofing the walls and glass. The can be achieved with the addition of concrete and steel wall supports. A “progressive collapse” structural design can be created to limit the likelihood of a complete building collapse in the event of an attack.

Perimeter security is typically created by the addition gates and entry areas and is most often delineated by a fence. ATFP fence can be a standard fence that is upgraded or one that is originally manufactured to ATFP fence specifications. ATFP perimeter security can be of a very different nature.  

ATFP Entry Systems or Gates are created by using passive and/or non-passive barriers.  These systems are specifically designed for the level of protection that the facility mandates.

Passive Barriers allow the passage of entering vehicles at all times. This can be achieved by placing jersey wall barriers in away that creates a maze for the vehicle to maneuver.  This effectively forces the vehicle to slow down while permitting access.  This is only one example of this type of passive barrier.

Non-Passive Barriers are actually permanent entry obstacles. These are things like bollards, wedge barricades, drop arms, slide gates and newly designed net systems. These Barricades can be used in conjunction with fence gates or can actually be mounted to fence gates. They are used more often than passive barriers because they can be moved in and out of their location with ease. This allows instant entry and immediately re-barricaded areas.

ATFP passive perimeter security can be accomplished with the use of steel cables or steel guardrails. This can also be setup by any combination of natural and manmade features when natural barriers are not sufficient or present. Distance can be a great ATFP device when used in combination with an uneven or bumpy surface. This can also be achieved with ditches and berms, or large bolder (3ft. x 5ft.) placement and forestation. This will slow down any moving vehicle or a truck bomb that is attempting to implode a building surface. Remember that AT/FP perimeters are specifically intended to stop only vehicle traffic. This perimeter prevents a bomb threat, not theft.  

Bear in mind that it is much easier to implement the AT/FP standards when working on new construction rather than attempting to retrofit the system into an already existing environment.  When retrofitting, much of the plan design work will be required to be done onsite and in an emergent way. This can lead to extreme design difficulties and can turn out to be very costly. Conceiving a building or site around AT/FP barrier implements is much easier than situating the AT/FP elements around already existing structures. Imagine attempting to widen the distance between a building and the adjacent road line. It would be much easier to initially plan this rather than propose it at a later point in time.

Some additional research should be done to understand ‘K ratings’ (K4|K8|K12). These ratings are somewhat complex and are standards set by the government to quantify and ensure the inflexibility of implemented AT/FP barrier devices.  Read ‘K ratings’ (K4|K8|K12 Fence) Informational Blog

Article contributed by fence professional John Lowndes.