A method and system for maintaining operator alertness comprises a detector for detecting a physical status of an operator. The physical status indicates a first level of operator alertness. A user interface requests a second level of operator alertness from a self-evaluation of the operator at a request time. An evaluator measures at least one of an accuracy of the operator response to the requested input and a response time of the operator from the request time. An alert module generates alarm data or an alarm signal to alert the operator based on the first level of operator alertness indicating an inattentive state and at least one of the measured accuracy and operator response time indicating the inattentive state.