49 C.F.R. § 229.123 Pilots, snowplows, end plates.
Title 49 - Transportation
After January 1, 1981, each lead locomotive shall be equipped with an end plate that extends across both rails, a pilot, or a snowplow. The minimum clearance above the rail of the pilot, snowplow or end plate shall be 3 inches, and the maximum clearance 6 inches.
Title 49: Transportation
PART 229—RAILROAD LOCOMOTIVE SAFETY STANDARDS
Subpart C—Safety Requirements
Cabs and Cab Equipment
§ 229.123 Pilots, snowplows, end plates.