CLEARSY
The CLEARSY company
CLEARSY was founded on January 1, 2001 by the team of engineers responsible for the industrialisation of the formal modelling tool called Atelier B, used in the railway sector to produce safety software.
CLEARSY: safety systems engineering
We are a French SME, specialised in the realisation of safety systems and software from level SIL1 to SIL4. We develop complex systems by ensuring their design, their validation, verification and safety study, right up to their commissioning.
CLEARSY produces safe systems and software in the railway, automotive, military, space and nuclear fields.
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News
CLEARSY Safety Platform, a computer for the safe control of equipments
7 October 2025 | Component
CLEARSY Safety Platform, a computer for the safe control of equipments. In 2021, CLEARSY pass the certification of its SIL4 […]
The B WORKBOOK is now available
1 October 2025 | Computer science
The user manual for B Method, the B WORKBOOK, is now available on CLEARSY’s GitHub: (https://github.com/CLEARSY/BWORKBOOK). After several months of […]
Artificial Intelligence and safety
30 September 2025 | R&D
In a recent study conducted under the direction of the Operations and Safety Department of the International Union of Railways […]
Safety is not an option: it is a requirement
23 September 2025 | Offers
Safety is not an option: it is a requirement. French railway operator RATP has once again demonstrated this by choosing […]
Let’s go for the CLEARSY’s lessons 2025-2026 in french universities
17 September 2025 | Company
To mark the start of the new academic year, CLEARSY is launching its 2025-2026 university course programme. Our teams will […]
CLEARSY provides an onboard computer simulator and an onboard test bench
16 September 2025 | ERTMS
CLEARSY is proud to share a contract with SBB CFF FFS for the supply of a simulator of the On-Board […]
Safety software and systems
All our security systems and software available below. If you have a specific problem, contact us.
operational systems
