43 C.F.R. § 420.11 Requirements—vehicles.
Title 43 - Public Lands: Interior
Each off-road vehicle that is operated on Reclamation lands shall meet the following requirements: (a) It shall conform to applicable State laws and vehicle registration requirements. (b) It shall be equipped with a proper muffler and spark arrestor in good working order and in constant operation. The spark arrestor must conform to Forest Service Spark Arrestor Standard 5100–1a, and there shall be no muffler cutout, bypass, or similar device. (c) It shall have adequate brakes and, for operation from dusk to dawn, working headlights and taillights.
Title 43: Public Lands: Interior
PART 420—OFF-ROAD VEHICLE USE
Subpart A—Operating Criteria
§ 420.11 Requirements—vehicles.

