I was traveling through Europe when the Barcelona attacks occurred last August. The Barcelona terrorist drove a van into the Las Ramblas, a tree-lined pedestrian mall popular with tourists. In a separate vehicular attack in Nice, France, on July 14, 2016, a truck plowed into and killed 86 Bastille Day vacationers. On August 7, 2017, in Stockholm, a terrorist hijacked and crashed a truck into a department store killing five people and wounding 14 others.
As I passed through several capital cities where similar attacks had occurred, I was apprehensive, but the engineer in me kept asking, “What are the simplest, most effective and low-cost countermeasures to prevent future vehicle attacks?”
Terrorism’s current weapons of choice are vehicles ranging from 2,400 lb. up to heavy trucks of 65,000 lb. or more. How effective are bollards and other vehicle barriers in stopping vehicular terrorist attacks? What are the vehicle crash rating test standards for these vehicular barriers? Are there additional countermeasures and emerging technologies for hostile vehicle mitigation (HVM) to prevent future pedestrian deaths?
While vehicles alone can be deadly, a VBIED, or vehicle-borne improvised explosive device, can cause even more destruction. VBIEDs can breach security systems without detection and deliver an explosive payload to unsuspecting occupants. The loss of life and suffering from vehicles can be stopped by increasing the deployment of simple pedestrian protection technologies such as bollards or other vehicle barriers. Barcelona esplanade is not protected by bollards (France 24 Video).
Terrorist attacks using vehicles have resulted in more casualties compared to bombing, shooting and stabbing attacks. Just Terror Tactics sections in jihadist magazines such as Rumiyah and Inspire actually provide grim instructions to terrorists on how to use vehicles to attack. These publications encourage terrorists to strike parades, open market squares, parks, university campuses, central business districts, shopping malls, strips, concerts, athletic arenas and other soft targets using large trucks.
Even without the consideration of terrorism, many pedestrian fatalities occur every year when vehicles collide into storefronts due to causes such as accidents, medical issues, DUI and ram raids. Accidental vehicle crashes into commercial, public and retail buildings occur more than 60 times per day in the U.S. based on the Storefront Safety Council’s statistics. Storefront crashes result in as many as 500 fatalities and more than 4,000 serious injuries annually. According to the Storefront Safety Council, over $100 million dollars in claims were paid in 2015 and 2016 because of vehicle-into-building crashes. The vehicle attacks on New York City's Times Square (May 2017) and New Orleans Mardi Gras (February 2017) were undertaken by deranged or intoxicated individuals.
Bollards and Barrier Countermeasures
NYC had installed bollards in October 2016 around Times Square, which is credited with saving many lives during the May 2017 attack. Cities around the world need to surround their soft targets or the busiest, most crowded areas with active or passive protective vehicle barriers.
Passive vehicle barriers are permanently closed. Active vehicle barriers (AVBs) open and close to allow passage of emergency, maintenance, personnel and delivery vehicles at certain times. AVBs can raise, lower, slide, swing or fold using hydraulic, pneumatic, electric, friction/gravity-drive or manual actuation. The barrier can be permanently fixed or temporary. Permanent barriers make sense for open market squares, parks, university campuses, central business districts, shopping malls, athletic arenas and strips. A variety of crash-rated vehicular barriers types are available such as bollards, cable barriers, drop arms or crash beams, inertial barriers, netting barriers, plate or wedge barriers and specialized proprietary barriers. Bollards or barriers can be fixed or removable. Gates, fences and guardrails can also be separate and protect pedestrians from traffic depending on their design. However, many fences, gates and guardrails are designed for perimeter protection or other purposes. Spike strips and speed bumps may not completely stop a vehicle, but they will slow down and reduce control.
According to the Department of Homeland Security's (DHS) Guide to Active Vehicle Barrier Specification and Selection Resources, AVB equipment, installation and maintenance costs are much higher compared to passive vehicle barriers.
The installed costs of active vehicle barriers ranged from $22,000 to $100,000 in the DHS guide. DHS recommends the use of good site design (traffic calming, minimizing entrances) and passive barriers. Active barriers are also more susceptible to tampering and degradation from the environment.
Passive vehicle barriers such as fixed bollards, concrete planters, Jersey barriers and impaler barriers had equipment costs ranging from $435 to $2,550 in the National Institute of Building Sciences’ Physical Security Design Manual for VA Facilities—Cost Estimates for Physical Security Enhancements publication.
Some vehicle barriers are designed to be mobile or portable. Mobile vehicle barriers are wheeled devices towed or driven to a site. Portable barriers are transported by truck or trailer. Mobile or portable temporary barriers should be installed to separate and protect pedestrians from vehicles around parades, political rallies, concerts and other transitory outdoor events.
Mobile or rapidly deployable barriers are required for parades, runs or marathons, festivals, carnivals, open markets, concerts, rallies or other transitory gatherings. The barriers need to be removed after the event ends. Mobile wedge barriers, cable barriers, net barriers, drop arms, crash beams and certain inertial barriers might be deployed to protect temporary assemblies or events.
Strategically deploying spike strips along potential attack routes can halt an assault as well. The Nice attacker drove for more than 1.5 km (one mile) before his killing spree was cut short.
Barrier Crash Rating Test Standards
Barriers are crash rated based on their stopping effectiveness in regards to the amount of kinetic energy (vehicle speed and mass) and penetration past the barrier. The kinetic energy of a 50 mph vehicle is 2.8 times higher than a 30 mph vehicle of equal mass. Barriers are evaluated based on kinetic energy ratings (DOS K ratings, ½mv2) and penetration ratings (DOS L ratings or ASTM P ratings). The penetration rating indicates the distance the front of the vehicle will go past the back end of the barrier. The U.S. Department of Defense (DOD), U.S. Department of State (DOS) and ASTM have testing standards for crash rating vehicle barriers. While the older DOS SD-STD-02.01 standard is now discontinued, many products still list barriers rating to this K-rating standard.
The ASTM F2656-07 Standard Test Method for Vehicle Crash Testing of Perimeter Barriers has superseded the DOD and DOS K-ratings system. DOD and DOS have both adopted the ASTM F 2656-07 standard for the certification and approval of vehicle barriers. The ASTM F2656-07 standard document outlines the differences of the most recent standards such as the CWA 16221:2010, ASTM F2656-07, BSI PAS 68:2013 and ISO IWA 14-1:2013. ASTM’s barrier rating system designates the vehicle mass and speed with a series of letters M, C, PU and H followed by the vehicle speed (30, 40 or 50 mph). An H50 rating corresponds to a 65,000 pound, heavy-goods vehicle traveling at 50 mph.
ASTM penetration ratings indicate the test vehicle's maximum dynamic distance of penetration after impact with the barrier. Typically, the dynamic distance is barrier face to the front of the cargo bed. The penetration rating indicates how far the front of the vehicle will travel past the back end of the barrier. If the building or pedestrian area is a safe distance from the barrier, then a higher ASTM penetration rating with a longer penetration distance could suffice and provide the required level of protection.
A detailed assessment of the potential threats needs, pedestrian traffic, vehicle access requirements, buildings and roadways needs to be undertaken before protective countermeasures can be designed for a city or facility. Department of Homeland Security’s Guide to Active Vehicle Barrier Specification and Selection Resources and other government-issued references below provide detailed guidance on site planning, design and barrier selection.
An additional countermeasure would be to slow down or calm traffic near areas crowded with pedestrians through enforced speed limits signage or physical deterrents such as speed bumps or additional turns in the roadways. Parking lots should be designed so a direct path does not exist to an area in front of or within a building where many people congregate. Parking spaces should point away from buildings and crowds of people. A slower vehicle does much less harm because impact damage is related to the kinetic energy (mv2), which scales with the square of the vehicle speed. Physical features of the site (natural terrain features such as trees, bodies of water, ditches) can serve as barriers.
Restricting access and vetting vehicles and drivers as they enter city areas can reduce terrorist incidents. London established a so-called "ring of steel" years ago when IRA terrorists were plaguing the city. The city of London's protective shield restricts vehicular access by only permitting entry at a handful of electronic checkpoints. Checkpoints could be set up around events where authorities would carefully inspect vehicles before permitting them to enter secure perimeters. The ring of steel consists of a contemporary defense system utilizing CCTV cameras, sentry boxes, bollards, one-way systems and planters to create an effective barrier. Up to four million CCTV cameras trace and capture the movements of people across Britain every day.
The lines of people entering checkpoints at concerts or events need to be protected as well. Checkpoints or screening stations require guardhouses, security systems, access control systems and security personnel.
Another countermeasure is making car and truck rental companies more rigorous in checking for fake IDs, counterfeit licenses and false insurance documents. If the weapon can be kept out of the hands of the terrorist, then the threat will be neutralized. Car and truck owners should not leave their vehicle running or unlocked. Jihadists will steal or hijack a vehicle for their suicide attacks. The terrorist in the vehicular attack in Stockholm in April 2017 hijacked a truck from a brewery. In the United States, a commercial driver's license is required for vehicles larger than 11,800 kilograms (26,000 pounds). Obtaining a commercial license requires a deeper vetting process, so perhaps the requirement for a commercial license should be applied to lower weight trucks as well. In the United States, the American Association of Motor Vehicle Administrators (AAMVA) provides a Driver's License Data Verification (DLDV) Service, which can be used by electronic ID verification devices and systems.
In Europe and the Middle East, Islamist extremists are more prevalent. In the United States, the vehicle ramming terrorists are not all radical Islamist extremists. The Charlottesville terrorist attack on August 12, 2017, was perpetrated by a white supremacist and neo-Nazi terrorist. In fact, a 2017 U.S. GAO report based on data from the U.S. Extremist Crime Database (ECDB) found three times as many fatalities causing extremist attacks were perpetrated by far right wing extremists compared to radical Islamist extremists between September 2001 and December 2016. Stopping the dissemination of extremist and Jihadist propaganda, blocking terrorist recruiting websites and deprogramming radicalized individuals are additional preventive countermeasures. Social media engagement and community counseling needs to be undertaken to counter and deter individuals from pursuing violent extremism. In the United States, local authorities may want to consider increased vetting before allowing extremists, fanatics or radicalized individuals entry into their cities. Limiting access may prevent future clashes between right-wing extremists and liberal city residents.
Emerging and Future Countermeasures
A long-term countermeasure could be autonomous emergency braking (AEB) systems, which would automatically stop a vehicle when a pedestrian is detected in front of the vehicle. Some vehicle OEMs already offer AEB as an option. In 2015 in the United States 35,000 people died from car accidents. According to NHTSA, research shows that 94 percent of crashes are tied to a human choice or error. Thirty years from now, most vehicles will be intelligent or autonomous and connected via wireless networks. On March 17, 2016, the U.S. DOT and IIHS announced a historic commitment from 20 automakers, who represent 99 percent of the U.S. auto market. The automakers agreed to make automatic emergency braking (AEB) standard on virtually all new vehicles no later than Sept. 1, 2022.
Today, electronic dog fences keep pets contained without a physical barrier. Perhaps laws could be passed to equip all vehicles or at least heavy trucks with GPS asset tracking technology to allow remote surveillance and eventually enable electronic car fences or geo-fenced virtual vehicle barrier zones. Police or security personnel would remotely demarcate the virtual geo-fence around esplanades, shopping areas, campuses or crowded arenas. Networked, autonomous vehicles would automatically slow down when entering a city or approaching geo-fenced zones. The connected vehicles would be incapable of intentionally driving into pedestrian crowds. A geo-fence could also detect and prevent an intelligent vehicle carrying a GPS-located firearm from entering a protected zone. Onboard AEB systems would provide an additional line of pedestrian protection. Compared to physical vehicle barriers, virtual vehicle barrier zones could be more rapidly and cost-effectively deployed around parades, concerts and other temporary gatherings. Vehicle autonomy and networking technology should be accelerated, so the age of intelligent vehicles and virtual vehicle barrier zones can become a reality sooner.
Today, the increased use of bollards and other vehicle barriers could shield innocent bystanders from intentional vehicular terrorist attacks and accidental collisions. Simple, permanent barriers such as bollards or inertial barriers can be deployed for a fraction of the cost of active vehicle barriers using hydraulic or electrical actuation. Passive barriers like bollards should have lower maintenance costs and better resistance to the environment. Active barriers like wedges, cable barriers or crash beams require warning lights and sirens to warn pedestrians and vehicles during actuation. Removable bollards might be the lowest cost protective option when vehicles only need to pass through infrequently. The design of bollards, planters, trees, decorative walls or large bronze sculptures can be thoughtfully integrated into the environment, so the subtle protection is provided without turning the city into a fortress. Cost-effective barrier countermeasures need to be more widely deployed in our cities and communities to stop future heavy vehicle attacks. In the long term, wider deployment of intelligently-networked vehicles could cost-effectively provide the best line of defense.
Protection against Malevolent Use of Vehicles at Nuclear Power Plants
Physical Security Design Manual for VA Facilities—Cost Estimates for Physical Security Enhancements
Anti-Vehicle Barriers for Public Transit—APTA Standards Development Program Recommended Practice, American Public Transportation Association
Australians seem to be jumping on the bollard bandwagon (https://www.youtube.com/watch?v=XHBmnX5nnUM and https://www.youtube.com/watch?v=tel99hcQftU )
Enough is Enough: The Times Square Crash Shows Need for More Bollards
Stopping Vehicular Attacks
The Bollard: Non-Crash and Non-Attack-Resistance Models
Preventing Vehicle Impact to Buildings
Front Parking Spaces and Building Protection
Parking Lot Safety and Traffic Flow
Rethinking Bollards: How Bollards can Save Lives, Prevent Injuries and Relieve Traffic Congestion in New York City