Perimeter Security and Physical Barriers Flashcards

The US Department of State's K-rating system for anti-ram barriers tests a vehicle at 50 mph. What does a K12 rating indicate?

Answer: The barrier stops a 15,000 lb vehicle traveling at 50 mph

A K12 rating means the barrier successfully stopped a 15,000 lb vehicle (medium-duty truck) traveling at 50 mph with no more than 3.3 feet of penetration beyond the face.

What is the recommended minimum distance between parallel rows of concertina wire on a high-security perimeter fence to slow intruder movement?

Answer: The rows should not be parallel but staggered

Staggering concertina wire rows in a pyramid or box configuration is more effective than parallel rows, as it entangles intruders more effectively and is harder to defeat.

Which fence type is recommended by ASIS for high-security applications due to its rigidity and resistance to cut-through attacks?

Answer: Welded wire mesh panel fence

Welded wire mesh panel fences (such as 358 anti-cut mesh) offer superior resistance to cutting and climbing compared to chain-link due to their rigid construction and small aperture size.

A security assessment reveals that an 8-foot chain-link fence has a gate that takes 90 seconds to close and lock. What vulnerability does this represent?

Answer: Perimeter delay vulnerability — insufficient closure speed allows vehicle intrusion

A slow-closing gate creates a perimeter delay vulnerability where a determined adversary can drive or run through before the gate secures, defeating the purpose of the barrier.

According to FEMA and DoD perimeter security standards, what is the recommended minimum clear zone width on BOTH sides of an outer perimeter fence?

Answer: 20 feet (6m) inside, 20 feet (6m) outside

A 20-foot clear zone on both sides of the perimeter fence provides unobstructed surveillance and eliminates concealment cover for approaching intruders.

What is a 'hostile vehicle mitigation' (HVM) strategy and when is it required in US federal facility security planning?

Answer: Physical measures to prevent vehicle-borne attacks; required when standoff distances cannot be met

HVM encompasses physical countermeasures (bollards, walls, ditches) to stop or deflect hostile vehicles, required by ISC standards when minimum standoff distances cannot be achieved.