Abstract
This paper proposes an operation navigation based on the operation procedure in an abnormal situation of a plant to prevent human comission errors by utilizing the advantageous feature of the control panel equipped with visual display units. An operation navigation system does not allow an operator action without following the operations described in operation manuals. This paper describes representation of the operation procedures specified in the operation manuals, algorithms for the operation navigation technique, and implementation for a pressurized water reacter plant.