The National Highway Traffic Safety Administration (NHTSA) announced yesterday it will begin a rulemaking procedure to mandate speed-limiting devices on heavy-duty trucks. The NHTSA action was a rather delayed reaction to petitions filed with the agency over four years ago by two trucking lobbys.

In 2006, both the American Trucking Assns. (ATA) and Road Safe America petitioned the highway-safety agency to look into devices that would set the top speed for heavy trucks at 68 mph.

Mandatory speed limiters, though, remain far from imminent. NHTSA does not expect to issue a formal Notice of Proposed Rulemaking before2012. While the rulemaking process is no guarantee of a rule ultimately being promulgated, the NHTSA announcement does put the devices front anc center before trucking.

Speed-limiters are already on the books in the Canadian provinces of Ontario and Quebec. The rules there require devices that limit trucks to running no faster than 105 km/h (65 mph).

“NHTSA’s announcement to conduct further research is the right move, especially as it considers the impact of improved fuel economy," David Kelly, a former Acting Administrator of NHTSA and now president of safety consulting firm Storm King Strategies, told Fleet Owner.

"While there is debate about whether speed limiters are an effective countermeasure to reduce fatalities, NHTSA will hopefully be able to answer that question definitively [in this rulemaking process]," Kelly said. "What we do know is that NHTSA will not move forward with a regulation if there is not a safety benefit [attached to it].”

Steve Keppler, executive director of the Commercial Vehicle Safety Alliance (CVSA), advised that “We’ve had a conversation about speed limiters for some time within our membership; we're still in a 'wait and see' mode regarding this proposed regulation. We haven't come out more publicly about speed limiters because it is not a simple issue."

For example, pointed out Keppler, consider the issue of aftermarket speed-limiter technology vs. OEM systems. "That is a complex issue in and of itself," he explained. "You have integration issues to look at, and what if the technology stops working? That brings up the other key part of this -- enforceability. How do we enforce speed limiters and ensure they are being used properly? That's another critical piece of this."

Make no mistake, Keppler stressed, speed is a major factor in highway crash fatalities. Therefore CVSA firmly holds that efforts to reduce speeding are vital. Yet he added that CVSA members are concerned that requiring speed limiters could create new safety hazards even as they address speeding. A key one is that speed differentials among different types of vehicles is already a major safety issue.

"That's why we think NHTSA is wise to take the path they are; this proposed rule won't be out until 2012,” added Keppler. “[That] gives time for people to look more closely at these issues -- to bump the speed-limiter conundrum up on their priority list, as it were."

At least one trucking lobby has come out strongly against the proposal. “Speed limiting a truck at 68 miles per hour, or at any other speed, will not improve highway safety,” said Todd Spencer, executive vp of the Owner-Operator Independent Drivers Assn. (OOIDA). “All credible highway research shows that highways are safest when all vehicles travel at the same speed and that different speeds for cars and trucks actually increase the likelihood of accidents.”

Spencer cited a study conducted by the University of Arkansas that showed “speed limit differences between trucks and cars increase speed differentials, which create more dangerous interactions between trucks and cars.” He also said another study, conducted by the University of Michigan Transportation Research Institute, shows that speed-limited trucks are “overrepresented in rear-end fatalities involving large trucks,” noting that just 4% of all trucks are speed-limited, yet half of the rear-end fatalities involving trucks were with speed-limited trucks.

He said that OOIDA contends that economics and the current per-mile pay structure for drivers is the “real motivation” to reduce the ability of trucks to run with the flow of traffic. “Hiring the most experienced drivers and paying them professional wages isn’t a priority for most large motor carriers and it’s cheaper to just govern the engine,” Spencer said.

“This isn’t a safety measure NHTSA is proposing” he Spencer. “It’s a permission slip for big trucking companies to remain unaccountable.”