Heavy-duty trucks would be required to have automatic emergency braking under new US rule

Semi trucks and other heavy-duty vehicles would be required to come standard with automatic emergency braking (AEB) under a new rule proposed today by the Biden administration. The announcement follows a similar rule for all new passenger vehicles proposed last month and is part of a larger effort to slow the increase in fatal traffic crashes in recent years.

The new rule would require heavy vehicles that weigh in excess of 10,000 pounds to come equipped with AEB, a technology that uses forward-facing cameras and other sensors to automatically apply the brakes when a crash is imminent. The system would be required to bring a vehicle to a complete stop at speeds as low as 6mph and as high as 50mph, the National Highway Traffic Safety Administration (NHTSA) said.

“We have been focused on this rule making really for many, many years,” NHTSA Chief Counsel Ann Carlson said at a press briefing Thursday.

Making AEB standard in all vehicles, both passenger and commercial, was included as part of the Bipartisan Infrastructure Law, which passed in late 2021. Supporters called it an important step toward the broader goal of improving road safety and reducing the number of vehicle crashes annually.

According to NHTSA, there are approximately 60,000 rear-end crashes a year involving a heavy vehicle striking another vehicle. Under the proposed rule, the agency estimates 19,118 crashes would be prevented, saving 155 lives and preventing 8,814 injuries annually.

After a 60-day public comment period, NHTSA will analyze the responses and make any necessary changes — a process that could take a few months. Carlson said she expects the final rule to go into effect sometime in 2024, at which point a phase-in period kicks off for truck manufacturers. For the heaviest trucks, Class 7 and 8, which typically weigh over 26,000 pounds, the effective date is three years from the rule going into effect.

Research has shown that current AEB systems are decent at preventing low-speed rear-end crashes but are less effective when vehicles are traveling at fast but still average speeds. The American Automobile Association (AAA) has been testing AEB systems for years and found a variety of common scenarios in which the braking technology completely fails to do the job as advertised.

T-bones and left-turn collisions, which account for around 40 percent of fatal crashes, are still almost impossible to prevent using AEB. Likewise, many AEB systems are crap at stopping vehicles from running over children, and at night, many of them are basically worthless.