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Train Dispatch and Preventing Start Against Signal SPADs
03/03/2020
A Start Against Signal SPAD occurs when a train proceeds from a stand towards a signal and passes it at danger. This type of SPAD can occur if when at a station the driver is inadvertently given an indication by station staff, or the guard, that platform duties are complete. If the driver does not check the signal before proceeding, a SPAD will result.
Research into dispatch risk demonstrates the risk of collision from Start Against Signal SPAD (SAS-SPAD) due to train dispatch is minimal. This is because errors from both the driver and person dispatching the train must happen for a SAS-SPAD to occur. SAS-SPADs are a problem because the signal may not be fitted with Train Protection & Warning System (TPWS), and if the driver is not aware of the signal aspect, they may continue taking power after the SPAD.
