In the trucking industry and commercial vehicle law enforcement, we have become accustomed to federal agencies, like the Federal Motor Carrier Safety Administration, creating regulations. We often forget that we have the power to petition for a new rule as well.

One company didn’t forget. Daimler Trucks North America (DTNA) wanted its automatic emergency braking (AEB) monitoring hardware installed on the inside of truck windshields. However, FMCSA regulations sought to protect driver vision by controlling the space where carriers can mount certain “Advanced Driver Assistance Systems” and allow only defined “vehicle safety technology” within that area. DTNA petitioned FMCSA to increase that approved area of the windshield and change the regulatory definition to accommodate AEB and other technologies.

DTNA won – and it didn’t.

FMCSA issued a final rule approving the greater windshield area sought by DTNA and the expanded definition of “vehicle safety technology.” At the same time, FMCSA excluded AEB from the expanded definition, deferring the possible inclusion of AEB until it conducts a congressionally-mandated rulemaking on automatic emergency braking.

Effective May 6, 2022, here are the changes made in the final rule:

Windshield Area

Federal Motor Carrier Safety Regulations (FMCSRs) prohibit obstruction of the driver’s field of view by devices mounted at the top of the windshield. Antennas and similar devices must not be mounted more than 6 inches (152 mm) below the upper edge of the windshield and must be outside the driver’s sight lines to the road and highway signs and signals.

An exception is allowed for defined “vehicle safety technology.” Those devices were allowed to be mounted:

  • not more than 4 inches (100 mm) below the upper edge of the area swept by the windshield wipers, or
  • not more than 7 inches (175 mm) above the lower edge of the area swept by the windshield wipers, and
  • outside the driver’s sight lines to the road and highway signs and signals.

With the final rule, devices with approved vehicle safety technology may be mounted on the inside of a truck windshield 8.5 inches (216 mm) below the upper edge of the area swept by the windshield wipers.

“Vehicle safety technology”

The old FMCSRs defined “vehicle safety technology” as systems and items of equipment to promote driver, occupant, and roadway safety. They included: fleet-related incident management systems, performance or behavior management systems, speed management systems, forward collision warning or mitigation systems, active cruise control systems, and transponders.

With the final rule, that definition is expanded to include: lane departure warning systems, braking warning systems, braking assist systems, driver camera systems, attention assist warnings, Global Positioning Systems, and traffic sign recognition. Vehicle safety technology includes systems and devices that contain cameras, lidar, radar, sensors, and/or video.

FMCSA also concluded that devices which had been granted temporary exemptions in the past would no longer need to apply for renewals.

What now for AEB?

DTNA may argue that AEB does “promote driver, occupant, and roadway safety.” FMCSA could bear that in mind when it conducts the automatic emergency braking rulemaking. Meanwhile, due to DTNA, the truck windshield is open to more safety devices over a greater area than before.