Safety critical and/or operational critical? MXSuite allows you to mark a category as critical. MXSuite offers the option to filter all tasks based on criticality. Using that, the worklist can be filtered on critical equipment. There are 2 types of critical marks: Safety critical: this is used to mark a category (equipment) as safety for ISM / class, such as a main engine. Operational critical: this is to mark a category (equipment) as safety for operational use, such as a towing winch. There are different icons used to indicate critical categories: Icon Explanation The category is marked as safety critical . The category is marked as operational critical . The category is marked as safety critical and operational critical. To mark a category as critical: Right-click on a category and select  Mark as safety critical or Mark as operational critical .