In the industrial maintenance field, critical tasks are activities that can endanger operating processes and cause serious accidents if not performed correctly. These tasks are typically performed by professionals with a considerable level of knowledge and rely on prescribed procedures that flag the task, drawing the attention of task performers. Given the importance of reviewing work procedures and monitoring tasks for human error prevention, this study analyzed similarities and differences in the visual attention of expert and novice task performers while following procedures with and without flagging of a critical task. The study included 48 maintenance professionals, divided into two groups of performers: experts and novices. For attention analysis, eye-tracking technology was used to monitor their observation during the work procedure, recording data on time to first fixation, total fixation time and number of visits. The results indicate that in the procedure without flagging of the critical task, the numbers of fixations on and visits to the stages of the task were higher in the novice than in the expert group. In the flagged procedure, the visual attention of experts and novices was similar when considering all stages of the task. In conclusion, the tasks must be revised between the two groups, and the flagged procedure can be used as a guide for work monitoring, helping experts or novices to more easily select relevant information.