A few points on Warning and Degradation Concepts in ISO 26262.
- Warning and Degradation concepts are defined as Functional Safety Requirements, and can be elaborated with specific requirements in system, hardware and software requirements.
- Warning and Degradation concepts should only be mentioned if it is not possible to reach safe state within the fault tolerant time interval(FTTI).
- Warning and Degradation concepts reduce the risk exposure time to an acceptable limit.
- Warning Concept: Warn driver regarding the inability to reach safe state and about the reduced functionality (if degradation has kicked in). For example: engine malfunction indicator lamp, ABS fault warning lamp.
- Degradation Concept: Reduced the functionality to reach the safe state. The driver should be able to handle the degraded functionality in a proper way.
- Degradation Concept: Reduced the functionality to reach the safe state. The driver should be able to handle the degraded functionality in a proper way.
- Emergency operation is a part of Warning and Degradation concepts.
- The Warning and Degradation concepts should be validated with System FMEA (after identifying Single point).
