欧洲铁路系统风险评估标准解析

Interpretation of Railway System Risk Assessment Standards in Europe

为了更好地理解欧洲铁路市场相关要求和以RAMS为关注点的欧洲铁路系统风险评估体系,介绍欧洲铁路系统风险分析评估框架,明确其风险评估的目的是得出可使铁路系统达到其安全目标的安全措施;以此为基础,解释了风险评估相关的风险分析、风险评价、风险接受原则、安全措施、安全需求等概念,介绍EN 50126等标准与欧盟CSM、TSI法规的关系。THR是铁路业主向承包商/设备商提出的定量安全要求,电气/电子功能安全是欧洲铁路系统安全性的重点和难点。TFFR是THR中可定量的功能安全失效部分,TFFR、SIL针对电气/电子安全相关功能,BI适用于TFFR大于1E-5 h^(-1)的安全相关功能和非安全相关功能;对于安全相关功能,SIL应根据最底层独立功能的TFFR进行分配,以体现SIL的功能属性。电气/电子功能安全以RAM知识为基础,仅关注其THR/TFFR不充分,应从其功能的RAM各方面全面考虑。

In order to better understand the relevant requirements of the European railway market and the risk assessment system of the European railway system focusing on RAMS,this paper introduces the risk analysis and assessment framework of the European railway system,clarifying that the purpose of its risk assessment is to derive safety measures that can enable the railway system to achieve its safety objectives;on this basis,it also interprets the concepts of risk analysis,risk evaluation,risk acceptance principle,safety measures and safety requirements related to risk assessment and introduces the relationship between standards such as EN 50126 and EU CSM and TSI regulations.THR is a quantitative safety requirement put forward by railway owners to contractors/equipment suppliers,and electrical/electronic functional safety is the focus and difficulty of European railway system safety.TFFR is the quantifiable functional safety failure part in THR,TFFR and SIL are for electrical/electronic safety-related functions,and BI is applicable to safety-related functions and nonsafety-related functions with TFFR greater than 1E-5 h^(-1);for safety-related functions,SIL shall be allocated according to the TFFR of the lowest independent function,which reflects the functional attributes of SIL.Electrical/electronic functional safety is based on RAM knowledge,and only focusing on its THR/TFFR is not enough.It shall be comprehensively considered from the RAM aspects of its functions.