As operations complexity grows, the risk of human error increases. According to the Abnormal Situation Management Consortium, operator error accounts for 42% of abnormal situations in industrial systems, which leads to economic loss and threatens workplace safety. Research by this group also determined that the loss of industrial system availability reduces production capacity by 3 to 8%.
Common HMI design mistakes
Conventional HMI design doesn’t take into account economic and safety goals. In addition, increasing data density makes it necessary for operators to cope with an overload of information presented in complex visual displays. Thus, handling alarms in a timely manner has become unmanageable, and spotting critical data trends using ineffective charts taxes the skills of even seasoned operators.
HMI design can also contribute to safety issues and industrial accidents, despite advanced alarm notification systems. In a recent survey by Automation World, 70% of respondents said “alarm overload” impacts their ability to properly operate the production process.
The heart of the dilemma is simple: HMIs used in industrial processes today were meant to maintain a particular operational state rather than to optimize business performance.
Situational awareness concept revolutionizes interaction
The ASM Consortium has found that an HMI design based on “situational awareness,” a methodology of best practices, can be five times more effective at recognizing a process under duress. This new approach can help overwhelmed operators to perform their jobs with fewer errors and can reduce unanticipated downtime.
Designing an HMI for added value
Today’s advanced technologies enable industries to implement the three pillars of a situational awareness design: perception, comprehension, and projection.
Applied to an industrial setting, situational awareness refers to an operator recognizing data, alarms or trends (perception), understanding how those elements affect the production process (comprehension) and predicting the consequences of future action or inaction (projection).
Best practices for HMI design:
- Goal-oriented design – Identify the major business goals of a system, such as energy usage, and break goals into sub-goals with parameters for an operator to make decisions.
- Window structure – To distill information and promote quicker comprehension, break down screen displays into a four-level hierarchical approach: Level 1 facilitates decisions to act or investigate. Level 2 enables execution. Level 3 provides equipment status details. Level 4 supplies information such as trend analysis, event analysis, alarm analysis, loop tuning, and help/procedural information.
- Color and animation – Abandon elaborate visual displays, which can confuse and distract operators. Use simplified, standardized colors and animation to focus an operator’s awareness as shown in this video.
- Actionable alarm management – Review alarm configuration to ensure each alarm will trigger only when an operator needs to take action to minimize the potential for nuisance alarms.
- Effective design elements – Use a standardized set of design elements to communicate key information in the simplest manner and reduce the cognitive load for operators, as shown in this video.
- Meters and dashboards – Use “smart” meters to enhance an operator’s ability for turning data into actionable information. Employ dashboard tools to help operators spot data trends.
The proper HMI design allows operations teams to shift their focus from straight operations to real-time business management. The ultimate benefit to an industry is a higher level of safety and better economic performance.