Explanations of the terms used in the possible tasks are as follows:

• • Lubrication/servicing (all categories)—this involve any act of lubricating or servicing for maintaining inherent design capabilities.
• • Operational/visual/automated check (hidden functional failure categories only)—an operational check is a task to determine that an item is fulfilling its intended purpose. It does not require quantitative checks and is a failure-finding task. A visual check is an observation to determine that an item is fulfilling its intended purpose and does not require quantitative tolerances. This, again, is a failure-finding task. The visual check could also involve interrogating electronic units that store failure data.
• • Inspection/functional check/condition monitoring (all categories)—an inspection is an examination of an item against a specific standard. A functional check is a quantitative check to determine if one or more functions of an item perform within specified limits. Condition monitoring is a task, which may be continuous or periodic to monitor the condition of an item in operation against preset parameters.
• • Restoration (all categories)—restoration is the work necessary to return the item to a specific standard. Since restoration may vary from cleaning or replacement of single parts up to a complete overhaul, the scope of each assigned restoration task has to be specified.
• • Discard (all categories)—discard is the removal from service of an item at a specified life limit. Discard tasks are normally applied to so-called single-cell parts such as cartridges, canisters, cylinders, turbine disks, safe-life structural members, and the like.
• • Combination (safety categories)—since this is a safety category question and a task is required, all possible avenues should be analyzed. To do this, a review of the tasks, which are applicable, is necessary. From this review, the most effective tasks should be selected.
• • No task (all categories)—It may be decided that no task is required in some situations, depending on the effect. Each of the possible tasks defined above is based upon its own applicability and effectiveness criteria.