On June 3 of this year, the U.S. Transportation Department announced that electronic stability control (ESC) systems will now be required on heavy trucks (truck tractors) and large busses weighing more than 26,000 pounds (FMVSS No. 136). But the initiative doesn’t stop there: the National Highway Traffic Safety Administration is attempting to expand the requirement to target medium-sized vehicles between 10,000 and 26,000 pounds as well. The rule is representative of widespread efforts to utilize technology for greater safety and efficiency on U.S. roadways.

The Federal Motor Vehicle Safety Standard No. 136 was put forth and finalized by NHTSA, and compliance with the new ruling will be carried out over the next four years, providing enough time for manufacturers to make necessary alterations. For most heavy trucks, compliance will be required in August 2017, but buses larger than 33,000 pounds will be given three years for compliance, while those weighing between 26,000 and 33,000 pounds will be given four years. The ruling comes as no great surprise, but indicates a positive focus on safety in the trucking industry.

What the ESC Ruling Means

The new ruling is expected to prevent an estimated 1,759 crashes a year and is seen as a step forward in safety precautions for both the public and trucking logistics. ESC technology is an electronic circuit that acts as a safety mechanism, automatically maintaining directional control of the vehicle if a driver is unable to brake or steer adequately to avoid wrecking. For example, during sudden lane changes or while turning a corner at high speeds, ESC can help prevent jackknifing, flipping, or skidding by automatically reducing engine power and applying selective braking.

The goal of the technology is to maintain directional stability, reducing the number of untripped rollovers while also rectifying severe understeer or oversteer conditions, which lead to a loss of vehicle control. By using a controlled closed loop algorithm, the computer in an ESC can correct yaw movement and enhance rollover stability.

There are two types of stability control systems that have been developed for heavy vehicles: ESC and Roll Stability Control (RSC), which prevents on-road untripped rollovers. ESC includes RSC and prevents Loss of Control (LOC) crashes. Rollover and LOC crashes have constituted a significant number of truck tractor and bus crashes over the years, but ESC is expected to reduce that number significantly.

Although still a growing technology, ESC’s are not new to the trucking industry. Light-duty vehicles have been required to include ESC’s ever since 2012. The NHTSA was urged to consider ESC requirements for motor coaches (which are now required) back in 2012 under the Moving Ahead For Progress in the 21st Century Act (MAP-21). ESC’s have been receiving greater recognition as vehicle safety technologies continue to develop and expand.

ESC Costs & Benefits

NHTSA Administrator Mark Rosekind champions the new ruling as one of both preventative safety and sound economic sense. Reducing the number of crashes each year not only saves lives, he argues, but it also makes transportation more efficient by reducing traffic delays and property damages caused by crashes. Because heavy trucks have more mass, varied cargoes, and often travel on large highways, heavy truck crashes cause greater property damage and more significant travel delays. As the logistics and trucking industry are under pressure to deliver products quickly and accurately, ESC’s aid in safe and efficient business.

According to the agency’s 2011 research note on the effectiveness of ESC’s, the systems are 28-36% effective in reducing untripped rollover. In the press release, U.S. Transportation Secretary Anthony Foxx noted that the ruling should provide net economic benefits of more than $300 million annually. The NHTSA estimates that 649 injuries and 49 fatalities will be avoided each year, and that 56%of untripped rollover crashes will be prevented. The net cost per equivalent life saved is estimated to range between $1.5 million and $2.6 million. Of course, the cost savings do come at a price: it’s estimated (in 2010 dollars) that an ESC system would cost roughly $1,160, including all components of the technology, with average incremental installment costs at $746 per vehicle.

Not only do ESC’s prevent accidents, they also act as a conduit for other life-saving technologies like collision avoidance systems, including Autonomous Emergency Braking (AEB). According to a Special Investigation Report (SIR) by NTSB on The Use of Forward CAS to Prevent and Mitigate Rear-End Crashes, commercial vehicles should have a ESC system in place first in order to receive the full benefits of AEB. Commercial vehicles equipped with both AEB and ESC systems would guard against more rear-end collisions. By making ESC’s a required feature of heavy trucks and busses, it may become easier to implement other precautionary technologies.

Robert Molloy, PhD, the Acting Director of the NTSB’s Office of Highway Safety considers the act to be a good first step. However, he points out the difficulties of applying the rule to all vehicles over 10,000 pounds, given that hydraulic ESC systems for commercial vehicles have only recently been deployed. Although the ruling is a step in the right direction, Molloy maintains that until the ESC ruling is expanded to vehicles under 26,000 pounds, unnecessary deadly crashes will continue to go unprevented. But in the mean time, the trucking industry will continue on with a greater focus on safety.