Driverless Truck Warning Beacons and the New Exemption
Published
Exemption in effect October 7, 2026 through October 7, 2031. Law checked through October 18, 2026.
Aeschylus opens the Agamemnon with a watchman on a palace roof, waiting for the chain of beacon fires that would carry news of Troy's fall across the Aegean. Light has always been the fastest warning a stopped force can send. The federal motor-carrier rules, written for a world with a driver in every cab, assumed something slower: a person walking back along the shoulder to set out triangles or flares.
A driverless truck has no one to walk. In a notice published October 9, 2026, at 91 FR 64736, the Federal Motor Carrier Safety Administration granted a five-year exemption from the warning-device rules in 49 C.F.R. §§ 392.22(b), 393.25(e), and 393.95(f) for trucks operated by a Level 4 automated driving system. The agency had refused similar relief in 2024 and later issued short-term waivers; this decision, effective October 7, 2026, runs to October 7, 2031.
The conditions are specific. The truck must carry amber, forward- and rear-facing flashing beacons mounted at least 100 inches above the ground, powered with redundancy, and activated within five minutes of an unplanned stop, along with the ordinary hazard flashers. It must stay within its validated operational design domain and may not carry passengers or hazardous materials, operate where a human driver would need certain endorsements, or pull more than two 28-foot trailers. Carriers must report any crash in which the beacons were or should have been on within five calendar days and file annual reports on use and malfunctions. Aurora may use the exemption directly; any other carrier must first notify FMCSA in writing, with a certification under penalty of perjury that it meets every condition.
Texas is the proving ground. The exemption's notice also states that, while it is in force, states may not enforce conflicting rules against interstate operations of carriers using it.
Limits
The exemption excuses three warning-device rules and nothing else; every other federal motor-carrier regulation still applies. FMCSA may revoke it for noncompliance or if safety declines.