Obstruction

Obstruction and its cognate expressions include a train, vehicle or obstacle on or fouling a line, or any condition which is dangerous to trains. (G.R. 1.02(43))

While dispatching/receiving a train into/from block section, it is must to ensure that line is free from any condition that is unsafe to train.

A section of track already occupied with a train, big stones on track, rail breakage, floods, trees fallen on track, level crossing gates in open condition etc., are some of the examples of obstructions.

In such occasions, generally trains shall not be dispatched without extra precautions.