Alarm Management is one of the control room systems that effect operator performance but there is a bigger picture. When we look at down time, we need to think about why we have operators in the control room and ask, are they effective at mitigating and managing abnormal situations?
Below is an example of the cost of downtime per the Emerson white paper “Improving Availability”
Consider a typical plant that generates $500 million per year in revenue at 85% availability. Each incremental hour of production is worth approximately $67,000. If variable costs are 60% of total cost, almost $27,000 of that added revenue is operating profit. In this case, increasing availability from 85% to 90% (reducing downtime by 438 hours per year) would boost annual profit by more than $11.7 million.
In the process industries, alarm systems are one vital tool, allowing plant operators to identify abnormal situations and respond effectively. These events can lead to personnel injury, environmental excursions, and commercial loss. Good alarm management practices are essential in a proactive control environment. When operators are forced to deal with hundreds of alarms at any given point in time, there is increased risk to safety, not to mention process efficiency. Everyone is working on some type of alarm management program however, many have not invested the same amount of time and resources on the HMI graphics, control room layout, fatigue mitigation, communication, work-team design, procedure handling, training, console ergonomics, and best practices that reduce operator error.
Operators are the first line of defense when upsets occur. The success and effectiveness of the control room operator is dependent on understanding plant issues and being able to quickly respond with the correct action, in time to solve the problem. Operators require human-machine interface (HMI) graphics that are easily understood and indicate when conditions are changing, as well as quick, easy access to supporting documentation. Graphics should be ergonomically designed, to stand out when a problem is building, to guide the operator to the cause of the problem, to aid in corrective action, before the alarms activate. So the company goal should be to create predictive operators not reactive operators.
An overall reduction in the number of operators in the process industries requires existing operators to know more of the plant and be able to operate more effectively. Training, simulators, and up to date documentation in linked to ergonomically written procedures. Both are equally important. Measuring operator workload is important and you have to look at normal workload and abnormal workload to make sure you have the right number of operators in the room and in the field. Staffing studies provide great insight to workload and breakdowns in situation awareness.
Operator performance has an impact on both safety, profitability, and quality. If operators are overwhelmed by nuisance alarms, they’re probably not operating the plant at peak performance. If the operator’s competencies are not high enough, they are more likely to make mistakes in carrying out alarm-related procedures or may not communicate effectively with other members of the operations team—again leading to errors. During normal operations, it is desirable to optimize the unit to reduce costs, minimize energy usage, increase yields, and increase feed rates. Highly competent operators will be able to do this well and also mentor their less experienced colleagues. Overall operating efficiency therefore increases. A properly designed training program can capture this tribal knowledge before senior operators retire. This should be happening now.
According to research by the Abnormal Situation Management (ASM) Consortium, the primary causes of major upsets or abnormal situations in industrial plants are 40% due to human error, 40% due to equipment failure, and 20% due to other factors. In addition, the studies show operating out of range causes equipment problems approximately 76% of the time. This is also a human error. The ASM research concluded that human performance contributes to 70% to 80% of all abnormal situations at process plants. Why don’t we focus on human side of operations, the operators, if we need them we should give them what they need.
Poor situation awareness will result in unplanned downtime. Operators must have a clear understanding of the process health and the ability to predict future problems without relying on the alarms. Situation awareness is absolutely critical if we want the operators to prevent and reduce unplanned downtime caused by process upsets. You cannot achieve situation awareness by simply focusing on alarm management, there are many other management systems that need the same attention and planning. Operator effectiveness is achieved when you address abnormal situations, human error, situation awareness, and human factors in the control room. Operator effectiveness should be studied, the gaps should be identified, and those gaps should be filled by implementing control room best practices.