Signals passed at danger | Office of Rail and Road

A signal is passed at danger (SPAD) when a train passes a stop signal when not allowed to do so.

SPADs are one of the potential precursors to railway accidents. Since the train protection and warning system (TPWS) was introduced serious SPAD incidents and the risk arising from SPADs have been greatly reduced.

We produce quarterly safety reports which include a summary of SPADS, this can be found on our data portal.

There are many SPADs each year, but most have little or no potential to cause harm because they are the result of minor misjudgements of distance or braking capability, or they occur at low speed. In most cases, the trains stop within the safety overlap provided at the signal.

The overlap is a clear section of track beyond the signal, usually 183 metres long, which protect against minor overruns. Generally, trains have to run past the safety overlap before there is any potential of collision or derailment.

SPADs are only one of the potential precursors to railway accidents. Since the train protection and warning system (TPWS) was introduced serious SPAD incidents and the risk arising from SPADs have been greatly reduced.