This part of the first defense focuses on preventing operator's actions that might divert the operational situation from normal to exceptional. It is applicable to certain types of operational errors, such as activating the wrong function.
The guidelines for preventing operator's errors are borrowed from the discipline of cognitive engineering.
To prevent such errors, except for special cases, the commands available to the operator should be restricted to suit the stage in the operational procedure, which implements the task in the active scenario. This implies that the operator's control over the machine should be limited .
Updated on 09 Mar 2017.