Within hours after the 9-11 attacks and prior to Congress allocating billions of dollars for anti-terrorist measures, government and military officials were already rushing deliveries of barriers and bollards, which will stop and destroy a truck with 30,000 pounds traveling at 50 mph. Such barricades can be raised or lowered at will to stop traffic or let it through. In an emergency, the thick steel plates or bollards pop out of the ground within 1.5 seconds.
Because of terrorist threats and tactics, vehicle barriers have become essential elements in an effective physical security program. When integrated properly into a total system, including fences, lights, alarms, gates, and other security components, vehicle barriers satisfactorily meet this threat to sensitive resources. (Pictured, installation protecting the New York Federal Courthouse was put in place just prior to the trial for the original Twin Towers parking garage bombing.)
Vehicle barriers should be used at vehicle access points to sensitive areas. Supplemental gate and fencing reinforcements may also be needed to optimize vehicle barrier effectiveness. Levels of force, number of personnel involved, tools and methods used vary and are determined by the perpetrator.
Delta barricades employ a patented design configuration in which a heavy steel weldment is rotated into guard position with its lower edges locked in linear sockets in the foundation. When the raised face of the ramp is impacted, the energy is first partially absorbed by the ramp and then is transmitted through the weldment into the foundation.
This design also permits the rapid cycling of the barricade from the full up to full down position or the reverse, typically in less than three seconds. Thus, it can be used to control normal authorized traffic with a minimum of delay but, in an emergency, the barricades can be raised to the guard position at maximum speed, between 0.6 and 1.5 seconds depending on barrier size. A surface barricade or gate capable of absorbing the same amount of energy would be many times larger and require tremendous amounts of energy to operate at the same speeds.
