Quantifying situation awareness of control room operators using eye-gaze behavior

•Loss of operator's situation assessment is a typical precursor to process safety incidents and accidents.•We seek to develop proactive strategies to assess operators' situation assessment.•Operator's eye gaze behavior is a direct indicator of operator's cognitive processes, especially during abnormal situations.•A entropy based measure is proposed to quantify eye gaze dynamics.•Experimental studies are conducted which validate the proposed entropy measure.

In an attempt to improve process safety, today's plants deploy sophisticated automation and control strategies. Despite these, accidents continue to occur. Statistics indicate that human error is the predominant contributor to accidents today. Traditionally, human error is only considered during process hazard analysis. However, this discounts the role of operators in abnormal situation management. Recently, with the goal to develop proactive strategies to prevent human error, we utilized eye tracking to understand the situation awareness of control room operators. Our previous studies reveal the existence of specific eye gaze patterns that reveal operators' cognitive processes. This paper further develops this cognitive engineering based approach and proposes novel quantitative measures of operators' situation awareness. The proposed measures are based on eye gaze dynamics and have been evaluated using experimental studies. Results demonstrate that the proposed measures reliably identify the situation awareness of the participants during various phases of abnormal situation management.