An incident where a train crew fails to stop short of a signal displaying a stop indication. This is one of the most serious operating rule violations in railroading, as it immediately compromises block safety and risks a catastrophic collision. It triggers immediate investigations, crew suspension, and mandatory drug testing.
Heard on the job
The dispatcher had to stop all traffic in the subdivision after that westbound freight had a signal passed at danger at milepost forty.
Insider tip
North American railroaders usually just call this 'running a red' or a 'stop signal violation', while SPAD is the formal regulatory term in the UK.
Also heard as
- SPAD