I'm trying to formulate some requirements using the ISO/IEC/IEEE 29148 standards. I know that the following is correct according to the standards.
The system [Subject] shall stop [Action] only when the stop-button is pressed [Condition].
I'm trying to do the same but for two conditions, as follows:
The system shall stop only when either the stop-button is pressed or when the x-things is reached.
I don't feel like this is correct but maybe it is? I couldn't find any straight-forward answer to my question in the standards but maybe someone here has some experience with writing formal requirements?