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 at the Heart of RSSRail 2025
19 November 2025 | Company
CLEARSY at RSSRail 2025: a key role in the organization and scientific program. CLEARSY will play a leading role at […]
HEXANA entrusts CLEARSY with the definition of sodium reactor control system
18 November 2025 | Company
CLEARSY has been assisting French start-up HEXANA with the design of the control system for its sodium-cooled reactor since May […]
Increased reliability with CLEARSY’s relays on the Paris Metro line 14
13 November 2025 | Company
CLEARSY’s RS4 safety relays are used by RATP for the safe management of platform screen door closure in metro stations. […]
CLEARSY: French railway safety in the spotlight at the Élysée Palace
13 November 2025 | ERTMS
On 15 and 16 November 2025, the autonomous train ECOTRAIN, selected for the “Made in France” exhibition at the Élysée […]
SIL2 safety development of the temporary signalling server (GEST) for ARGOS RBC
4 November 2025 | ERTMS
CLEARSY is carrying out the safety development with a SIL2 requirement level for the temporary signalling server for Compagnie des […]
CLEARSY systems in Volume 5 of ‘Railway Signalling and Automation’ book
29 October 2025 | Offers
In this reference work, the chapter entitled ‘Full automation of a metro line’ refers to two CLEARSY safety systems without […]
Safety software and systems
All our security systems and software available below. If you have a specific problem, contact us.
operational systems
