Glossary · Change, versions and configuration
Impact analysis
Also known as: Change impact analysis
In systems engineering and functional safety, impact analysis is the analysis of which requirements, risks, interfaces, tests, documents and operations may be affected by a change. It determines the scope of reassessment and re-verification.
- Systems engineering
- Functional safety
- Verification
In one sentence
Impact analysis determines which requirements, risks, interfaces, tests, documents and operations a change may affect before it is approved.
Example
Before replacing a safety laser scanner on an AGV with a newer model, the impact analysis identifies the changed response time, the affected protective field calculation, the validation tests and the service manual pages.
How it applies
- Functional safety: IEC 61508 expects the effects of a modification on functional safety to be analyzed before it is carried out. The result decides which safety lifecycle phases are repeated.
- Machine safety: Check the change against the risk assessment: new hazards, changed risk estimates, affected safeguards.
- Evidence: Use traceability to find affected tests and claims. Record why unaffected evidence remains valid.
- Technical documentation: Include instructions, warnings, training material and translations in the analysis. They are often forgotten because they are not in the engineering tools.
Impact analysis vs. risk assessment
A risk assessment evaluates the risks of the machine. An impact analysis evaluates what a change touches, which can include the risk assessment itself. It does not replace updating the risk assessment where risks change.