Vigilance tasks with a high level of attentional demand are becoming more frequent in daily work. High levels of attentional demand are required in critical systems, such as air traffic control, crowd monitoring, visual quality inspection, or sports.In a previous study, we introduced an ecologically valid test for screening visual attention in the general working population. The test requires participants to complete a visual search task at a moderate level of difficulty. In the present work, we increased the test's level of difficulty to enable accurate screening of high levels of attentional skills. To establish reference data, attentional skills were recorded in 60 participants, ranging in age from 19 to 40, performing the test at both, moderate and high levels of difficulty.Increasing the difficulty level of the test resulted in a lower test performance score. Furthermore, an increased level of difficulty reduced the ceiling effects caused by highly-skilled participants. In the present report, we provide normative performance score data and evidence for the reliability of the developed test. Adapting the level of difficulty enables our attention test to effectively screen for attention in occupations requiring moderate or elevated attentional skills. Relevance to industryDemands for visual attention are increasing in a variety of industries. Therefore, screening for attentional performance is becoming more important in accident prevention and quality of work. A previously-reported ecologic test for screening visual attention at a moderate level of attention was adapted to enable screening at an elevated level of attentional demands.