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ahtd-inspect-1-lo.jpg Photo: Rusty Hubbard/Arkansas State Highway and Transportation Department

Speed limiters: State agencies question federal role, roadside details

Commercial vehicle enforcement agencies share many of the same real-world concerns expressed by carriers and drivers in formal comments on the DOT-proposed truck speed limiter mandate, such as the safety risks posed by speed differentials and “elephant races” on the freeways. But the enforcement side of the regulation also have concerns unique to their roles, ranging from roadside technical details to whether or not the federal government has any business imposing a one-size-fits-all speed limit on states that better understand their own highway systems.

The Commercial Vehicle Safety Alliance, which represents local, state, provincial, territorial and federal truck safety officials and industry representatives, says it generally supports the deployment of proven safety technologies.

“The proposal on speed limiters represents an encouraging step towards addressing CMV-related crashes and fatalities,” the alliance writes. However, CVSA points to several “questions and concerns” that should be addressed, and requests the agencies issue a “supplemental” notice of proposed rulemaking answering their questions along with those from other stakeholders before issuing a final rule.

Concerning a “lack of clarity regarding scope of enforcement,” CVSA argues FMCSA’s directive that enforcement be conducted in a “targeted manner, periodically or randomly” may result in confusion and inconsistent levels of enforcement across states.

“Does FMCSA anticipate enforcement only take place when a CMV is observed speeding over the set speed?” the comment asks. “Or should enforcement of the speed limiter requirement be conducted as part of inspections roadside and at inspection facilities?”

CVSA would also like agency to add a speed-limiter check to roadside inspections, giving enforcement personnel the option of carrying a verification device, “similar to how states incorporate performance-based brake testers” into their inspection process.

The alliance also would like clarification of FMCSA’s position on “prima facie” violations, when a vehicle is observed exceeding the maximum set speed.

As to malfunctioning devices, the proposal represents “a departure from protocol” for CMV inspections and may result in making the proposed rule “vulnerable to fraud” because it allows drivers and carriers to avoid violations by not speeding.

“The proposed provision makes the rule unenforceable at roadside,” CVSA says. “FMCSA should clarify that a malfunctioning device is a violation and that drivers cannot avoid documentation of the violation, if identified by an inspector.”

CVSA also notes that members have suggested the use of speed limiter device readers could create a conflict with some electronic logging devices (ELDs). “Currently, some CMVs have ELDs that are not hardwired to the electronic control module (ECM) and are instead plugged into the same port that enforcement would need to plug the speed limiter reading device into. This forces inspectors to disconnect the ELD, which is problematic.”

And CVSA supports adding a retrofit requirement to the rule, simply because so few vehicles would be subject to the mandate if it only applies to new trucks.

The Texas Dept. of Public Safety points to a 2006 study by the University of Arkansas, and cites several findings in its comment on the speed limiter proposal:

  • While slower speeds increase vehicle performance (braking, maneuverability, etc.) they also mean that trucks are moving slower than cars which increases the number of vehicle interactions (cars passing trucks) which can decrease safety;
  • Slower vehicle speeds increase the amount of driving time and increase driver fatigue;
  • Increased driving time increases the amount of time it takes to deliver goods, and causes goods to cost more; and
  • Split speed limits decrease fuel economy in cars and non-regulated trucks by causing them to decelerate and then reaccelerate to pass regulated trucks.

“The Texas Highway Patrol recognizes that a mandatory speed limiter (60 mph, 65 mph, or 68 mph) would create a split speed limit on most rural highways and have negative effects on rural highway safety and congestion,” the comment reads, noting that Texas highways have varying maximum posted speed limits as authorized by the Legislature, the Texas Department of Transportation and local entities and often vary between 70 mph and 85 mph—resulting a potential, legal and “dangerous” speed differential up to 25 mph.

Texas DPS points to highway congestion, as well.  “Anyone who has driven on rural highways with two lanes going in the same direction has been caught behind one truck passing another truck at speeds below the posted speed limit. This backs up car traffic behind them and causes frustration which can lead to aggressive driving.”

The comment also notes that Texas previously had different speed limits for passenger cars and commercial vehicles. The Texas Legislature changed that to the current speed laws.

“In summary, the Texas Department of Public Safety believes that speed limits should be set and managed by the State of Texas and its leadership, and not as a one-size fits all interstate commerce regulation,” DPS says.

The Michigan Dept. of Transportation worked with the Michigan State Police, Commercial Vehicle Enforcement Division, to develop it comments, and MDOT, too, contends that proposed rule amounts to a “federally-mandated national speed limit” for trucks—one that doesn’t take into account “varying conditions and geography” among the states and preempts existing laws in at 35 states.

This comes as Michigan State Legislature is considering raising truck limits above some of the set speeds proposed in the rule, MDOT notes.

“This rule would be contrary to the intent of Congress to relieve states from mandated speed limits, as expressed in the National Highway System Designation Act of 1995, which repealed the national maximum speed limit,” the agency says. “MDOT believes that the ability to establish and amend speed limits should be left to each state as Congress intended. Therefore. MDOT recommends that no rule be issued at this time that would require speed-limiting devices to be installed in new trucks, nor in existing trucks.”

MDOT also points to the risk of increased interactions and the speed differentials between slower-moving trucks and other traffic on the freeways, and to the delay of light-duty vehicles by trucks overtaking other trucks “at very small differences in speed,” already a problem on the state’s major interstates. “A mandated maximum speed will likely lead to a large number of trucks operating at almost exactly the same speed, further worsening this problem.”

MDOT concludes that delays would be minimized by a set speed of 68 mph or higher, “allowing operators some freedom” to select individual speeds. A national truck speed limit of 65 mph would require some Michigan carriers to “adjust operating practices,” the comments stat6es, while a set speed of 60 mph would “impose significant costs” on Michigan truck operators and shippers, and would “worsen congestion, delay, and crash risk” on Michigan freeways.

TAGS: News Safety
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