Kavach 4.0 functions as an Automatic Train Protection system. It controls train speed, prevents Signal Passed at Danger (SPAD), and reduces chances of head-on or rear-end collision

Indian Railways has commissioned Kavach 4.0 on the Bajwa (Vadodara)–Ahmedabad rail section in Gujarat. The system is now operational across the 96-km route, covering 17 stations, according to the official announcement.
The work includes the setup of 23 towers, 20 Kavach buildings/huts, 192 km of optical fibre cable, and installation of 2,872 RFID tags.
The first train to run on the Kavach-enabled section was Sankalp Fast Passenger (59549/59550), operated with WAP-7 locomotives and 11 LHB coaches.
Kavach 4.0 functions as an Automatic Train Protection system. It controls train speed, prevents Signal Passed at Danger (SPAD), and reduces chances of head-on or rear-end collision.
The system supports loco pilots by automatically applying brakes if the train exceeds permitted speed or when safety is at risk. It includes SOS support and automatic horn activation at level crossing gates.
Kavach has been implemented on more than 2,200 route kilometres across the network. The system is indigenously developed and certified to Safety Integrity Level–4. The new version has been approved by RDSO after safety assessments and field experience.
Key upgrades in Version 4.0 include more accurate train location tracking, improved signal information in complex yards, optical fibre based station-to-station connectivity, and integration with electronic interlocking systems for better coordination. The system has been cleared by the Independent Safety Assessor to meet global safety norms.
The commissioning of Kavach 4.0 on this section marks continued deployment of Indian Railways’ indigenous safety technology and supports safer train movement and reliable operations across the network.