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Barriers are used in physical security to define boundaries, delay or prevent access, restrict movement to a particular area, obscure visual observation into or from an area, and prevent technical penetration of an area. When barriers are selected and installed properly, they can represent not only a physical impediment but also a psychological deterrent to an attacker.

Image of indoor benches made of concrete and wood placed to direct pedestrian traffic flow as well as provide a seating area.

Manmade structural barriers and natural barriers are two general types of barriers. Often, both types are used to secure Forest Service facilities. Other types of barriers (human barriers, such as guards; animal barriers, such as dogs) are beyond the scope of this Web site.

Manmade structural barriers include fences and walls, doors, gates, turnstiles, vehicular barriers, glazing (usually glass), and nearly all building materials.

Image of a visitor center that sits on the very edge of a steep cliff.

Natural barriers include berms, rocks, trees and other foliage, water features, sand and gravel, and other natural terrain features that are difficult to traverse or that expose an attacker.

Barriers, whether natural or manmade, must be tested regularly and maintained. Barring any unusual occurrences, an inspection every week or two generally is adequate.

To the greatest extent possible without sacrificing security, barriers should be esthetically compatible with your facility. This is more than a “look nice” issue. Physical security measures should not attract undue attention to your facility. Putting an eight-foot chain link fence with twisted and barbed top selvage topped with barbed tape obstacle (BTO) around your facility and then illuminating the facility like Yankee Stadium is an extreme example of how security might attract unwanted attention. On the other hand, very large rocks or boulders can be just as effective as manmade bollards in blocking vehicular intrusion without causing someone to wonder why such security measures were needed. Foliage can be a highly effective visual and physical barrier.

The barriers you select and install to keep attackers out also may keep rescuers out. Work closely with public safety first responders to ensure they know the barriers you have used and where they have been deployed.

Barriers also can work against you psychologically. The more imposing the barrier and the more impenetrable it looks, the more likely employees are to presume that anyone inside the barrier (inside the “secure” area) belongs there. An effective barrier does not immediately guarantee everyone inside is supposed to be there.



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