EN 50126-1:1999

This European Standard: defines RAMS in terms of reliability, availability, maintainability and safety and their interaction; defines a process, based on the system lifecycle and tasks within it, for managing RAMS; enables conflicts between RAMS elements to be controlled and managed effectively; defines a systematic process for specifying requirements for RAMS and demonstrating that these requirements are achieved; addresses railway specifics; does not define RAMS targets, quantities, requirements or solutions for specific railway applications; does not specify requirements for ensuring system security; does not define rules or processes pertaining to the certification of railway products against the requirements of this standard; does not define an approval process by the safety regulatory authority. This European Standard is applicable: to the specification and demonstration of RAMS for all railway applications and at all levels of such an application, as appropriate, from complete railway routes to major systems within a railway route, and to individual and combined sub-systems and components within these major systems, including those containing software; in particular: to new systems; to new systems integrated into existing systems in operation prior to the creation of this standard, although it is not generally applicable to other aspects of the existing system; to modifications of existing systems in operation prior to the creation of this standard, although it is not generally applicable to other aspects of the existing system at all relevant phases of the lifecycle of an application; for use by Railway Authorities and the railway support industry. NOTE: Guidance on the applicability is given in the requirements of this standard