Safety approval process

The approval process can be parted into three different types of approvals.

1) A "Generic Product (GP)" approval (the platform).

2) A "Generic Application (GA)" approval (the type).

3) A "Specific Application (SA)" approval (the installed product).

This is shown at Figure 9 in EN50129:2003, see below:


Interpretation

If e.g. Windows for PC was used as a railway product in e.g. a supervisory system, then the approval process could be parted into e.g.:

GP; the platform: This could e.g. be an American version of Windows, running on a PC.

GA; the type: This could e.g. be a Spanish version of Windows version, running on the platform PC.

SA; the installed product: This could e.g. be the Spanish Windows version physically installed at a supervisory centre at a site.

It works well in the theory, but it is difficult to part a complex system like Windows, a train or an interlocking system sharply into the three different systems definitions, GP, GA and SA.

Most often an approval process is connected to a contract concerning a specific application (SA). Everybody works hard to make the system ready and in this process the different System Definition's GP, GA and SA gets mixed with ambiguous interfaces.

But the basic idea is well-thought in order to approve a basic system in different country specific variants in the European countries and the parting should be strived towards.

Next chapter >> 3.1 EN 50126 key documents

Focus on the sources (EN 50129:2003)

Chapter 5.5.2, "Safety approval Process" describes the approval process. The approval concepts of GP, GA and SA are shown in EN50129:2003 at Figure 8 (see below and please excuse the quality).