30 C.F.R. § 56.9319 Going over, under, or between railcars.
Title 30 - Mineral Resources
Persons shall not go over, under, or between railcars unless: (a) The train is stopped; and (b) The train operator, when present, is notified and the notice acknowledged.
Title 30: Mineral Resources
PART 56—SAFETY AND HEALTH STANDARDS—SURFACE METAL AND NONMETAL MINES
Subpart H—Loading, Hauling, and Dumping
Safety Devices, Provisions, and Procedures for Roadways, Railroads, and Loading and Dumping Sites
§ 56.9319 Going over, under, or between railcars.

