The Safety Goals view is by a system Architect and is used for identifying safety goals that will mitigate the hazardous events that have been identified. They are basically the resulting output from the HARA work. Functional safety requirements will refer to safety goals to fulfill the functional safety goals of the project. A safety goal points to hazardous events. The inherited ASIL of the safety goal is based on the highest ASIL of the referenced hazardous events. This article describes how to work in the view.
- Getting Acquainted with the View
- Creating a Safety Goal
- Adding an Existing Safety Goal
- Editing a Safety Goal
- Deleting a Safety Goal
- Mapping Item Status
- Fixing a Version Mismatch
- Handling Mapping Errors
Safety Goals can refer to Safe Modes. A safe mode is the state that the system is switched into
to avoid risk. In the safety model, only existing safe modes can be referenced under a Safety Goal. No new Safe Modes can be created here. The reason is to keep the data persistent in the database and between different groups.
Getting Acquainted with the View
|Note: There may be hazardous events in the analysis area structure tree that are not displayed in the view. This is because the view can be configured to only display events with an ASIL value of a certain level, e.g., !=QM.|
Creating a Safety Goal
If a hazardous event has been identified and there is no existing safety goal in the server that already mitigates it, you will want to create a new safety goal. New safety goals should only be defined if the hazardous event is not already mitigated by an existing safety goal. To create a new goal, right-click on a hazardous event and select Create Safety goal.
In the Add new mapping dialog, a Name suggestion will be provided, but it can be changed as needed. Enter values for any attributes that are presented as well. Click OK to create the safety goal mapping item. It will display both in the tree and in the view.
Adding an Existing Safety Goal
If a safety goal is identified as being applicable for multiple hazardous events, it can be applied multiple times. To reuse an existing safety goal, right-click on the hazardous event and select Add existing Safety goal....
Editing a Safety Goal
Deleting a Safety Goal
To delete a safety goal, right-click on it and select Delete Safety goal. Multi-select is not supported.
The selected safety goal is removed. If it is not being used for another hazardous event, it will also be removed from the server.
Mapping Item Status
Fixing a Version Mismatch
A version mismatch occurs when the version of the hazardous event in the safety goal mapping item is different from the version of it in the
To fix, right-click on the safety goal and select Fix version. Then select the option to change the version in the model to match the version in the view.
Handling Mapping Errors
Out of Scope
After creating a safety goal, if a new hazardous event is added to it that is not in the master list of hazardous events, the safety goal will be highlighted red in the view to indicate that one of its items is out of scope. In the below example, a new hazardous event "High speed highway rain of IV hazard 2" was added via the tree to the "XYZ of High speed highway snow of IV hazard 2" safety goal. However, it is not in the master list.
To fix, copy the hazardous event and add (Paste) it to the master list under the harzard identification item ("Cruise control").
If one of the required items is missing in the tree for a safety item in the view, the safety item will appear dark gray. In the below example, the safety goal is missing a hazardous event as noted by the error message above the safety goal.
To fix, add the missing hazardous event to the safety goal in the tree.