Asking Users: A Continuous Usability Evaluation on a System Used in the Main Control Room of an Oil Refinery Plant

This paper presents a case study that observes usability issues of a system currently used in the main control room of an oil refinery plant. Poor usability may lead to poor decision makings on a system, which in turn put thousands of lives at risk, and contributes to production loss, environmental impact and millions dollar revenue loss. Thus, a continuous usability evaluation on an existing system is necessary to ensure meeting users’ expectation when they interact with the system. Seeking users’ subjective opinions on the usability of a system could capture rich information and complement the respective quantitative data on how well the system is in supporting an intended activity, as well as to be used for system improvement. The objective of this survey work is to identify if there are any usability design issues in the systems used in the main control room at the plant. A set of survey questions was distributed to the control operators of the plant in which 31 operators responded. In general, results from the quantitative data suggest that respondents were pleased with the existing system. In specific, it was found that the experienced operators are more concerned with the technical functionality of the system, while the lesser experienced are towards the system interface. The respondents’ subjective feedback provides evidences that strengthen the findings. These two concerns however, formed part of the overall usability requirements. Therefore, to continuously improve the usability of the systems, we strongly suggest that the system be embedded with these usability aspects into its design requirements.