Page 68 - 捷運技術 第43期

62 Andrea Colini 系統保證歐規與美規之介紹

3eCenelec Standards

European Standards can be applied systematically by a railway authority and railway support

industry, throughout all phases of the lifecycle of a railway application, to develop railway specific

RAMS requirements and to achieve compliance with these requirements.

For railway applications, the European Committee for Electrotechnical Standardization,
CENELEC, has produced a number of standards addressing the functional safety of railway

applications.

Whilst EN 50126 (RAMS) applies to the total railway system, the remaining standards, EN
50129 (safety), EN 50128 (software) and EN 50159 (communication) are applicable to a "complete

railway signalling system" including its individual sub-systems and items of equipment.

Figure 1cCoverage of CENELEC Standards

EN 50126 is the top-level document that covers the overall process for the total railway system.
It defines a comprehensive set of tasks for the different phases of a generic life cycle for a total

rail system and provides baseline information on the subject of RAMS and RAMS Engineering,

linking RAMS to Quality of Service. It identifies the elements of railway RAMS and "defines a
process to support the identification of factors which influence the RAMS of railway systems". It

then describes "the means to achieve RAMS requirements" and the concepts of risk, safety integrity