As with many other sites producing high-value products in a continuous 24 hour a day process, the number of operators required is a significant cost factor. For each operator workplace the company needs to have five operators on its payroll.
Originally, a total of 11 operators were required for each shift. Two of them were in the control room, the rest handled manual activities around the plant. In the course of the automation projects this number of operators could be reduced to five. Since then the expansion of the plant itself has resulted in this figure rising to eight. It is nevertheless a significant achievement that the total number of operators has been reduced from 11 to eight even though the production volume has been doubled.
The ergonomics of the plant operation was a key focus right from the original engineering phase and the close partnership between customer and supplier was essential in finding the optimum solution. Much of this is a matter of attention to detail. For example the control room is laid out to minimize distractions and the operators can access the company-internal administrative systems on the control system monitors so they do not have to leave their workplace. In addition, they can decide dynamically which information goes to which workplace.
Further ergonomic aspects go deeper into the ABB system. For example, when a high priority alarm occurs, the system suppresses alarms with lower priority to avoid distraction. Also, for special operations, the two workplaces can be divided into four to accommodate additional operators.