barrieranti-ram barrieranti-terrorism
perimeter securityhomeland securitybuilding protectionPRO Barrier Engineeriing, LLC
facility protectionAbout Ussecurity planningEmploymentvehicle barrierContact Usbollard
lorry barriersbarrierbarriercrash barrier
mobile barrierpermanent barrierportable barrier
Advancing the science of anti-terrorism vehicle access control


Vehicle Barriers Vehicle Barriers
Engineering Services Engineering Services
  What are the Different Types of Vehicle Barriers?
  How Important Are Barrier Aesthetics
  Is My Facility a Candidate for Vehicle Barrier Protection?
  How Does the U.S. Government Certify Barrier Stopping Power?
  Is Certification Essential?

Frequently Asked Questions

Q: How Does the U.S. Government Certify Barrier Stopping Power?

Stopping PowerA: Vehicle barrier certification is the responsibility of the U.S. Department of State. They have to protect U.S. installations around the world. Many of those facilities — embassies, consulates, and so on — are old buildings in dense urban areas. Sometimes the adjacent streets are only yards from the buildings or the grounds. This proximity of the traffic means the agency needs barriers that can stop an attacking vehicle dead in its tracks, not merely slow down or partially disable it. As a result, the department assumed the responsibility to develop standards for crash testing and certifying what it commonly calls anti-ram barriers.

Crash BarrierThe department released the first standards in 1985, and revised them in 2003. They were based on the mass and the speed of the attacking vehicle (really the vehicle's kinetic energy), and how far past the point of impact any significant piece of the vehicle traveled. They required a supplier to conduct a full-scale crash test at a State Department certified facility. Many certified vehicle access control barriers on the market today were tested to the 1985 standards and were given one of the ratings shown below. Note that these standards allowed vehicle penetration distances of up to 50 feet beyond the impact point. Certification confirms the utility of vehicle barriers for Anti-Terrorism Force Protection (ATFP).

Summary of U.S. Department of State 1985
Certification Standards
(outdated, see 2003 below)

If a barrier stopped a 15,000-pound truck traveling at a certain speed and the truck penetrated the barrier a certain distance, it was given a combination letter and number rating according to the table below.

Speed at Impact
Speed Rating
Penetration Distance
Penetration Rating
30 mph
< 3 ft
40 mph
3 - 20 ft
50 mph
0 -50 ft

For example, if a barrier stopped a 15,000-pound truck traveling at 40 mph and the truck penetrated six feet beyond the impact point, the barrier received a K8/L2 rating.

Vehicle BarriersIn 2003 the State Department released a revised certification standard, which is summarized below. In the intervening years the agency had identified a number of deficiencies in the earlier version, including:

  • Significant design differences between gasoline and diesel trucks. The new standard requires diesel test trucks.
  • More realistic requirements for attaching the payload to the truck. Rather than using a concrete monolith to achieve the desired weight as the old standard allowed, test trucks must now have 55-gallon drums filled with sand or soil and strapped to the truck's open, flat bed.
  • Penetration distance is now measured from the cargo bed's leading edge, not the front of the truck. This is because the State Department is ultimately concerned about explosives in the cargo area, not vehicle penetration per se.
  • The need for more stringent penetration limits. The new standard limits the penetration of the front of the cargo bed to 1-meter (3.3 feet). Further penetration means the barrier fails the test.

Summary of U.S. Department of State
2003 Certification Standards

If a vehicle access control barrier stops a 15,000-pound truck traveling at a certain speed, AND the front edge of the truck's cargo bed does not penetrate more than one meter beyond the pre-impact inside edge of the barrier, then it is given a rating according to the table below.

Speed at Impact
Barrier Rating
30 mph
40 mph
50 mph

For example, if a barrier stops a 15,000-pound truck traveling at 40 mph and the front of the cargo bed penetrated one foot beyond the impact point, the barrier receives a K8 rating.

Note that the new anti-ram barrier ratings do not allow any penetration beyond a nominal three feet. The State Department adopted this provision because — as noted above — many of their facilities are close to public access roads, and the pressure pulse on a nearby building from an explosion increases significantly as the distance to the building decreases.

With these new standards, portable or mobile vehicle access control barriers will no longer meet the 1-meter criteria because they dissipate impact energy by sliding on the road surface. These barriers have become quite popular in recent years for temporary security, particularly at military bases and high-profile events. This has complicated procurement because the purchaser of a portable barrier may be getting exactly the technology needed, but will not get the often-required certification to the latest State Department standard. This is an example where certification is not always an advantage to the end user. (See Is Certification Essential?)

In partial response to this change in State Department standards, the American Society for Testing and Materials (ASTM) has established a standards committee to develop a new vehicle barrier standard to complement — not supplant — the State Department one. This standard will probably allow some degree of vehicle penetration, and will identify alternative attack vehicles, including automobiles and light trucks. It may even extend the standard up to barriers rated to withstand the impact of a 60,000-pound truck.

In addition, the Department of Defense, the U.S. Navy, and the Department of Energy have separate standards targeted to specific applications. Our Vehicle Barrier Seminar discusses the new State Department standards in detail, explains these alternative certification efforts, and covers a broad range of other practical vehicle barrier topics.



PRO Barrier Engineering LLC / 100 Brown Street #24 / Middletown, PA 17057
717-944-6056 /

Home / About Us / Employment / Contact Us
Vehicle Barriers / Engineering Services / Frequently Asked Questions
What's New / Barrier Briefs Blog / Just For Fun