铁路应用 可靠性、可用性、可维护性和安全性(RAMS)的规范与论证 第1部分：通用RAMS流程

[中文适用范围]： IEC 62278-1:2025 专门针对铁路领域的具体需求，有效控制和管理RAMS（可靠性、可用性、可维护性和安全性）元素之间的冲突。本文件规定了以下内容： a) 基于系统生命周期及其内部任务的RAMS管理流程； b) 一种可依据系统类型和规模进行调整的系统化流程，用于规定RAMS要求，并证明这些要求得以实现。 本文件未规定以下内容： c) 针对特定铁路应用的RAMS目标、数量、要求或解决方案； d) 与本文件要求相符合的铁路产品认证相关的规则或流程； e) 铁路利益相关方的审批流程。 本文件适用于铁路应用领域，包括信号系统、机车车辆和固定设施，并特别适用于以下内容： f) 对所有铁路应用的RAMS进行规定和验证，包括从完整的铁路系统到主要系统，以及这些主要系统内的各个子系统和组件（包括含软件的系统）； - 特别适用于新系统； - 适用于集成到已获认可的现有系统中的新系统，但仅限于新系统与新功能相关的部分； - 对于现有系统未修改的部分，本文件不适用； - 在合理可行的范围内，适用于已获认可的现有系统的修改和扩展，但仅限于系统被修改的部分； - 对于现有系统未修改的部分，本文件不适用； g) 应用生命周期的所有相关阶段； h) 适用于铁路责任方和铁路供应商。 本文件不适用于以下情况： i) 现有系统的任何未修改部分； j) 未作修改的现有系统，包括已符合IEC 62278:2002的系统。 本版文件（与IEC 62278-2一起）取代并取消了IEC 62278:2002。本版文件为技术修订版。与前一版相比，本版文件包括以下重大技术变化： a) 增加了第5.2节，关于多层次系统方法； b) 增加了第5.3节，关于铁路系统概述； c) 增加了第5.9节，关于风险降低策略； d) 更新了第6.2节中RAMS管理流程与系统生命周期之间关联的内容； e) 增加了第6.4节，关于组织要求； f) 增加了第6.5节，关于本文件的应用及其对项目范围和规模的适应性； g) 增加了第6.8节，关于独立安全评估； h) 增加了第8章，关于安全案例； i) 增加了附录D，提供系统定义的指导。 IEC 62278系列是IEC 61508在铁路领域的具体应用之一。IEC 62278、IEC 62279和IEC 62425在铁路通信、信号和处理系统方面，构成了IEC 61508系列的铁路领域等效标准。一旦证明符合这些文件的要求，就不需要进一步评估符合IEC 61508系列的要求。所有IEC 62278系列的文件清单，标题为《铁路应用 – 可靠性、可用性、可维护性和安全性（RAMS）的规定与验证》，可在IEC网站上找到。 [外文原描述]： IEC 62278-1:2025 addresses railway specifics, enables conflicts between RAMS elements to be controlled and managed effectively. This document specifies: a) a process, based on the system life cycle and tasks within it, for managing RAMS; b) a systematic process, tailorable to the type and size of the system under consideration, for specifying requirements for RAMS and demonstrating that these requirements are achieved. This document does not specify: c) RAMS targets, quantities, requirements or solutions for specific railway applications; d) rules or processes pertaining to the certification of railway products against the requirements of this document; e) an approval process for the railway stakeholders. This document is applicable to railway application fields, including signalling, rolling stock and fixed installations, and specifically: f) to the specification and demonstration of RAMS for all railway applications and at all levels of such an application, as appropriate, from complete railway systems to major systems and to individual and combined subsystems and components within these major systems, including those containing software; in particular: - to new systems; - to new systems integrated into existing systems already accepted, but only to the extent and insofar as the new system with the new functionality is being integrated. It is otherwise not applicable to any unmodified aspects of the existing system; - as far as reasonably practicable, to modifications and extensions of existing systems already accepted, but only to the extent and insofar as existing systems are being modified. It is otherwise not applicable to any unmodified aspect of the existing system; g) at all relevant phases of the life cycle of an application; h) for use by railway duty holders and the railway suppliers. This document is not applicable to: i) any unmodified aspects of the existing system; j) existing systems which remain unmodified, including those systems already compliant with IEC 62278:2002. This first edition, together with IEC 62278-2, cancels and replaces IEC 62278:2002. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition: a) added 5.2 on multi level system approach; b) added 5.3 on railway system overview; c) added 5.9 on risk reduction strategy; d) updated the content of correlation of RAMS management process and system life cycle in 6.2; e) added 6.4 on organizational requirements; f) added 6.5 on application of this document and adaptability to project scope and size; g) added 6.8 on independent safety assessment; h) added Clause 8 on safety case; i) added Annex D providing guidance on system definition; The IEC 62278 series forms part of the railway sector specific application of IEC 61508. IEC 62278, IEC 62279 and IEC 62425 comprise the railway sector equivalent of the IEC 61508 series so far as railway communication, signalling and processing systems are concerned. When compliance with these documents has been demonstrated, further evaluation of compliance with the IEC 61508 series is not foreseen. A list of all parts in the IEC 62278 series, published under the general title Railway applications – Specification and demonstration of reliability, availability, maintainability and safety (RAMS), can be found on the IEC website.