Functional Safety Documentation: What Auditors Ask For
The four documents
| Document | Content |
|---|---|
| Safety requirements specification | Functions, required PL/SIL, reaction times |
| Design file | Architecture, components with declared PL/SIL, wiring |
| Verification record | Calculation plus measured stopping times |
| Validation record | Each function tested, dated, signed |
Questions that expose weak files
- Which standard edition did you apply, and why?
- How was the required performance level derived?
- Show the measurement of the achieved stopping time.
- What changed since the last validation?
A calculation that does not match the wiring on the machine fails audit. Keep as-built drawings in the same folder as the calculation.