2. General approach

Before tackling the specific problem of dynamic systems, it is useful to recall the general approach of a dependability study.

It's an iterative process involving more or less the same stages:

• 1. precise definition of the system to be studied ;

• 2. definition of the purpose of the study to be carried out ;

• 3. system functional analysis ;

• 4. dysfunctional analysis: identification and prioritization of risks, modeling; qualitative analysis; quantitative analysis ;

• 5. discussion with specialists/synthesis and decisions ;

• 6. results: specifications; test programs; maintenance policy; assessment of residual risk/production losses.