Glossary

T-12

The ability of passengers to obtain travel information, make reservations and book tickets in advance is affected by changes to the timetable caused by Network Rail taking possession of lines in order to maintain, renew and enhance the network. Under Condition 2 of its network licence, Network Rail is required to ensure that accurate timetable information is available to train operators at least twelve weeks in advance. 

TOC on TOC

Where a delayed train service of one train operator delays those of another train operator.

TOCs

Train operating companies: run the (passenger and freight) trains and services on the network. The representative body for the passenger operating companies is the Association of Train Operating Companies (ATOC).

TOPS

Total operations processing system.

Track circuit

Track circuits are designed to detect the presence of a train, by use of an electrical circuit which is completed by train wheels and axles.

Track circuit failure

Failure of a track circuit or associated equipment, including axle-counter failures.

Track geometry

The level and alignment of the track.

TSR

Temporary speed restriction imposed for safety reasons. This can arise from the poor condition of track, structures, earthworks, hot weather effects, or following track relaying until the track bed is stabilised.

TSR (COT)

A type of Temporary speed restriction that has been imposed specifically due to the poor Condition of track (COT).