A type of Lockout SystemA system which allows a person requiring access to the track to provide personal protection by restricting or preventing the signalling of trains. More that allows a PatrolmanA person who patrols/inspects a section of line. More, with the permission of
the SignallerA person responsible for the operation of the Signalling System, to safely control the passage and regulation of trains, usually located in a Signal Box. More, to prevent the signalled movement of traffic, for example, in
one direction only on a Bi-Directional LineA line on which the signalling permits trains to be signalled normally in either direction. See Bi-Directional Signalling More.