Vehicle Barriers vs Resistance Barriers for Transportation Projects

Resistance barriers come in many forms, but they all share one purpose: to stop or slow a vehicle while reducing risk to its occupants. These systems are engineered to capture and decelerate an oncoming vehicle in a controlled manner, using energy absorption to safely dissipate kinetic energy. The result is greater protection for drivers, passengers and the vehicle, with a reduced likelihood of severe injury or structural damage.

How Barrier Crash Testing Works

Regardless of application, crash testing is a precise and highly controlled process. Independent third-party facilities use vehicles of specified weight—defined by the standard—and launch them at the barrier at a set speed and angle. Evaluators then measure performance outcomes, including:

• Vehicle type and weight
• Impact speed and angle
• Vehicle penetration (how far a vehicle moves past the barrier after impact)
• Structural damage to the vehicle and cabin

This rigorous methodology ensures that energy absorption barriers meet the highest levels of safety, reliability, and consistency.

ASTM Crash Standards vs. MASH Standards

Unlike ASTM F2656 Standards, commonly used for pedestrian safety and anti-terrorism, the MASH Crash Standards for resistance barriers are different as they as focused on roadway environments, driver protection, and minimizing crash severity. This distinction is critical when determining which standard best applies to a project.

• ASTM F2656 Standards – In the United States, the most widely recognized crash test standard for vehicle barriers is ASTM F2656 (preceded by the U.S. Department of State crash standards). Unlike MASH standards, ASTM products are not primarily designed to protect drivers or passengers; they are engineered to stop vehicles and protect the surrounding environment. Their goal is to safeguard pedestrians, property, and critical infrastructure from intentional or accidental vehicle intrusions.

For example, the City of Las Vegas installed ASTM M50-rated bollards along sidewalks on the Las Vegas Strip to shield pedestrians from vehicle intrusion, while New York City similarly placed ASTM crash-rated bollards along bicycle lanes to protect cyclists.  To ensure the protection of pedestrians and cyclists on the other side of the bollards – the design teams selected bollards tested with a 15,000 lb. vehicle traveling at high speeds and with less than 3 feet of penetration.  These vehicle barriers are also commonly used to protect city events that take place in city streets, i.e., tourist areas, farmers markets, parades, protests, etc. So aside from their standard security applications, they are also a best practice for minimizing the risks of vehicle intrusion in high risk pedestrian corridors. 

In addition, the USDOT Safe Streets 4 All (SS4A) Grant Team formally recognizes their application as acceptable for implementation grants if the requesting municipality meets the requirements and has a safety action plan.  Should interested municipalities not have a safety action plan, the grant can additionally fund that as well.

• MASH Standards – On the other hand, the MASH (Manual for Assessing Safety Hardware) Standards, established by the U.S. Department of Transportation (DOT), are designed specifically for roadway and traffic environments. These include highways, movable bridges, managed lanes, and other transportation corridors with heavy vehicle traffic. The focus of MASH testing is on protecting vehicle occupants and reducing crash severity, while also minimizing vehicle damage. In short, MASH is about driver and passenger safety in everyday traffic scenarios.

What to Know About MASH Crash Ratings

The long-standing NCHRP Report 350 has been replaced with the AASHTO Manual for Assessing Safety Hardware (MASH). This transition updates testing to reflect today’s vehicle fleet and creates clearer, more consistent standards for roadside safety hardware.

MASH testing applies to guardrails, crash cushions, bridge barriers, and other roadside hardware, ensuring that these systems perform effectively when struck by vehicles at specific speeds and conditions.

The MASH Resistance Barrier crash test evaluates the performance of the resistance barriers to ensure they can safely stop or redirect vehicles.   The rating ranges from TL1 – TL6, with TL1 being the least resistance and TL6 being the most resistance.  The higher the rating, the more challenging the vehicle must be to stop or redirect within the barrier’s design.

Types of MASH Rated Resistance Barriers on US Roadways

On U.S. roadways, you’ll find a wide variety of barrier systems, including:

• Guardrails (W-beam and thrie-beam)
• Cable barriers
• Concrete barriers (jersey and F-shaped)
• Crash cushions / impact attenuators
• Bridge end & guardrail terminals
• Median barriers
• Movable bridge resistance barriers
• Managed lane resistance barriers

When sourcing a barrier for a movable bridge or managed lane, agencies must carefully evaluate their impact scenarios. For managed lanes, this often means designing around inbound and outbound lane restrictions.  B&B Roadway has Vertical Lift Resistance Barriers, and many other vertically and horizontally operated resistance barriers to accommodate just about every design application.

MUTCD Standards for Movable Bridges

For movable bridges such as draw bridges and swing bridges, the MUTCD Manual (Part 41) outlines standards for Warning Gates, including design, placement, and lighting requirements:

• Gate Arm Design – Must meet or exceed railroad gate dimensions, with 16-inch diagonal red and white reflectorized striping.
• Location Requirements – Gate arms must extend across the full roadway width; on divided highways, all approach lanes must be covered.
• Lighting & Signals – Flashing red lights (per railroad standards) must be mounted to the gate arm and activated when closing or closed. If warning and resistance barriers are both present, the warning gate must still include flashing lights.
• Additional Guidance –
  • Placement ideally within 50 feet of the gate.
  • Gate arms must be lightweight with sufficient clearance when raised.
  • If traffic may back up onto a railroad crossing, additional signs or devices are required.
  • When stopping immediately at the bridge isn’t feasible, gates should be placed one span away, with a second set ~100 feet from the span if the distance exceeds 330 feet.

At B&B Roadway, we manufacture a full line of crash-certified arm and net-style barriers, including dual-rail and tri-rail barrier arms, vertical lifts, and horizontal-swing net barriers. For over 40 years, our systems have been trusted on bridges and managed lanes nationwide—providing proven performance, long-term durability, and reliable protection for critical transportation infrastructure.