The National Highway Traffic Safety Administration (NHTSA) and the Federal Motor Carrier Safety Administration (FMCSA) are jointly proposing an automatic emergency braking standard for all heavy vehicles above 10,000 pounds (vehicle classes 3-8).

Commonly referred to as AEB, the technology uses cameras and radar to detect stopped, decelerating, or slower vehicles in the path of a truck. It then sends a visual and audible warning to the truck driver and automatically applies the brakes. If the truck driver manually applies the brakes, AEB supplements the driver’s effort as needed.

Under the proposal, manufacturers would also equip all included medium and heavy vehicles with electronic stability control (ESC). ESC modulates individual brakes and engine torque to reduce potential rollover and swerving. Trucks and most buses in classes 7 & 8 (26,000 pounds and above) are already required to have ESC under Federal Motor Vehicle Safety Standard (FMVSS) No. 136.

NHTSA has authority over new vehicle standards. Its portion of the joint proposal covers the equipment requirements and testing procedures. FMCSA, in turn, proposes the presence and activation of AEB and ESC in the affected heavy vehicle classes and the ongoing maintenance of the equipment for the useful life of the vehicle.

NHTSA and FMCSA do not propose retrofitting of AEB for existing heavy vehicles which already have ESC, or AEB plus ESC for vehicles not already subject to FMVSS No. 136. Instead, the joint proposal would require truck tractors and large buses currently subject to FMVSS No. 136 to meet the proposed requirements within three years of the final rule publication. It also calls for those heavy vehicles not presently covered by ESC regulations to meet all requirements within four years. Small-volume manufacturers, final-stage manufacturers, and alterers would be allowed one additional year, for five in total.

The cost/benefit analysis in the NHTSA/FMCSA Notice of Proposed Rulemaking (NPRM) weighs heavily in favor of benefits. Experts expect the proposed rule to substantially decrease risks associated with rear-end, rollover, and loss of control crashes. The NPRM predicts AEB and ESC together will prevent 19,118 crashes each year, including 5,691 crashes involving class 7 & 8 heavy vehicles. The proposal will save an estimated 155 lives annually and avoid 8,814 non-fatal injuries. The cost: $353.3 million at the time of new vehicle purchase, with safety benefits reaching nearly $3 billion.

NHTSA and FMCSA acknowledge that AEB is not 100% effective in all crash situations. The cost/benefit numbers in the NPRM were accordingly adjusted for AEB effectiveness. Driver alertness is still a necessity for optimum highway safety.  Still, AEB and ESC will reduce overall fatalities, injuries, and property damage even where a rear-end crash is not completely avoided.

NHTSA recently issued a similar AEB proposal for light vehicles, including the detection of pedestrians by passenger cars.  That light vehicle proposal would be effective four years after its final rule.

Comments on the NHTSA/FMCSA heavy vehicle automatic emergency braking proposal are due by Sept. 5, 2023.

The PrePass blog and podcasts are published as a public service of PrePass®, the most reliable and technologically advanced weigh station bypass and integrated electronic trucking toll payment platform in North America. PrePass also includes INFORM™ Safety and INFORM™ Tolling software for improving truck safety scores and lowering toll costs.