One of the most cost efficient anti-ram options to create perimeter security as well as protect buildings and their occupants is a cable barrier or passive cable barrier because it is fixed in place and has no moving parts, unlike an active device like a wedge barrier or retractable bollard.
These tension cable systems use extremely strong, steel barrier cables strung between less resilient posts allowing the wire barrier to absorb the kinetic energy of a motor vehicle and thus prevent complete penetration.
Many cable barriers are used along highways to prevent vehicles from leaving the roadway or colliding with cars traveling in the opposing direction. These types of barrier cable systems are held to testing standards created by the National Cooperative Highway Research Program (NCHRP) and examine three main factors, structural adequacy, occupant risk and vehicle trajectory. NCHRP 350 guideline has six testing levels depending on the vehicle size/type, speed and impact angle. Interestingly, testing level three, for small cars traveling at 60 mph, encompasses the majority of U.S. automobiles. Not surprisingly, most of the traffic-dedicated barrier cable is rated at NCHRP TL-3 and TL-4. However, TL1-6 is not the same as anti-ram rated cable barriers. Therefore, when contacting cable barrier systems suppliers, be sure to indicate whether your project requires an anti-ram rated cable barrier.
Crash-rated, anti-ram cable barriers are used to protect high-value targets like embassies, military installations, nuclear plants, petro-chemical facilities or airports and data centers.
An anti-ram cable barrier system is designed and engineered to prevent an intentional Hostile Vehicle Attack (HVA) by stopping incursion as fast as possible. Often these intentional attacks are at high speed and directed head-on at their target(s). Minimizing the penetration distance of an HVA is critical because often the car or truck is carrying an explosive payload. Denying penetration creates a greater the standoff distance from an explosion making it safer for people and building.
Cable barrier systems designed for less intentionally criminal actions like accidents or road hazards. When protecting drivers, the NCHRP 350 employs a different strategy than the ASTM’s anti-terrorist concerns. A highway tension cable system is engineered for more incremental control of the impact or crash. The goal here is to mitigate damage and reduce injury by having the barrier cable absorb as much of the car’s energy as possible rather than immediately and catastrophically stopping the vehicle in its tracks. Such a violent, instanteous halt at high speeds would, more often than not, seriously injure or kill vehicle occupants, even with airbags. In fact, traffic cables are often specifically designed to avoid the car directly impacting an anchored post which cause more severe damage.
The simplest way to think about the difference between the goal of ASTM standards and NCHRP 350’s is the former is almost exclusively concerned with protecting what is OUTSIDE the hostile vehicle – innocent pedestrians, buildings, etc. The NCHRP 350 is focused on protecting what is insde the vehicle – drivers and passengers – while insuring that the crash itself does not adversely impact what is outside – namely other cars and drivers.
Many anti-ram vehicle barriers are extremely expensive and often designed to protect access entry points. These products can be gates, crash arms, wedge barriers or retractable bollard arrays. Cable barriers also work well in these locations, and they have the added advantage of being capable of combined use with perimeter security fencing. Most cable barriers are not only less expensive, but they often are easier to install and thus offer additional cost savings.
Protogetic offers the largest selection of anti-ram cable barriers in the protective design industry, allowing our Users to search the important details their project requires. We even make it simpler by offering an incredible Compare Tool that displays your cable barrier choices side by side for easier evaluation. And if you have questions, with one click, you can chat directly with a manufacturer representative. Finding the best cable barriers has never been easier. Join us today at Protogetic.com!