49 U.S.C. § 20501

Definition

In this chapter, “signal system” means a block signal system, an interlocking, automatic train stop, train control, or cab-signal device, or a similar appliance, method, device, or system intended to promote safety in railroad operations.

( Pub. L. 103–272, § 1(e) , July 5, 1994 , 108 Stat. 883 .)