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What Are Truck Speed Limiters and Why Aren’t They Mandatory Yet?

What Are Truck Speed Limiters and Why Aren’t They Mandatory Yet?The Federal Motor Carrier Safety Administration, or FMSCA, is set to unveil its final proposal on speed limiters for commercial trucks later this year. Right now, speed limiters, which restrict vehicles from going above a certain speed, are not required on commercial vehicles in the United States. However, the plan is to make this technology mandatory over the coming years – a safety measure we applaud.

In April of last year, the FMCA announced a Notice of Intent of their plan to make speed limiters mandatory in commercial motor vehicles (CMVs), stating in part:

FMCSA is moving forward with this rulemaking because of concerns about the number of CMV crashes and fatalities traveling at high speeds. In 2019, there were 860 fatal crashes in areas with posted speed limits of 70 to 75 miles per hour. Twenty-four fatal crashes in areas with posted speed limits between 80 to 85 miles per hour. Approximately 20 percent of fatal crashes occur in areas with posted speed limits in these ranges. The rule will help reduce crashes and save lives on our nation’s roadways.

After this announcement, reactions were mixed. Critics of the program say speed limiters can cause more truck accidents. They believe that if commercial trucks are not permitted to travel at the same rate of traffic, the differential in speed could be dangerous. For example, if trucks are in both lanes of traffic traveling at the speed limit, they could cause a “rolling roadblock.” Other drivers might get frustrated at slower commercial vehicles and cause accidents trying to pass them improperly.

Safety advocates, however, talk about the benefits speed limiters can offer, like added safety and fuel savings. For example, the Truck Safety Coalition reports that speed specifically is a “significant factor in fatal crashes and speed management [is] a primary tool to reduce serious injuries and fatalities.”

The Coalition also notes that over 1,000 Americans are killed annually as a result of speeding trucks. And, speed limiters are effective in other countries and don’t seem to cause accidents:

An Ontario Ministry of Transportation study found that speed-related, at-fault collisions involving large commercial vehicles fell by 73% after the speed limiter requirement went into effect.

The same study ALSO found there is “absolutely no evidence” speed limiters contributed to an increase to inadvertent crashes w/passenger vehicles due to differences in speed.

The United States is the only leading country without standard commercial vehicle speed limiters. Further, rulemaking requiring the use of speed limiters in CMVs has been delayed over 20 times in the past 10 years. The Truck Safety Coalition states – and we absolutely agree – the “FMCSA must expeditiously complete rulemaking to require compel the use of speed limiters installed on Commercial Motor Vehicles.”

You can read more about the FMCSA’s Notice of Intent to proceed with the use of speed limiters on CMVs here.

How do speed limiters work?

Speed limiters on commercial trucks are designed to restrict the maximum speed at which the vehicle can travel. They work by using electronic controls to limit the amount of fuel and air that the engine can take in, thereby “capping” the top speed of the truck. Here’s the general way speed limiters work on commercial vehicles:

  • The vehicle’s computer reads the truck’s current speed through the use of sensors.
  • If the truck’s speed exceeds the preset limit, the computer sends a signal to reduce the amount of fuel and air entering the engine.
  • This reduces the engine’s power output, and the vehicle slows down to a speed below the preset limit.

Speed limiters can be set to different maximum speeds, depending on the type of vehicle and the regulations in the jurisdiction where it operates. They are usually preset by the manufacturer, but can be adjusted by a qualified technician if needed.

Will speed limiters help reduce truck accidents?

It’s likely speed limiters will help reduce truck accidents, which is why the FMSCA is recommending them. Speed limiters can reduce the risk of speed-related accidents, as well as the severity of those accidents that do happen. This can help reduce catastrophic injuries in the event of a serious truck accident. Finally, commercial trucks outfitted with speed limiters can potentially help truck drivers learn safe driving habits and reduce speeding and reckless driving.

The Savannah truck accident attorneys at Harris Lowry Manton LLP are keeping a close eye on this news and will be sure to keep you informed when the FMSCA unveils their final requirements. If you have been injured in a truck accident, we want to help. Talk to us today about how we can help you fight for compensation for your damages and losses. To schedule a consultation with an experienced attorney, call our offices or complete our contact form today. We have an additional office in Atlanta, and serve clients throughout Georgia.

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