What does the margin symbol (I) refer to in a maintenance context?

In a maintenance context, the margin symbol (I) specifically relates to inspections conducted by a Quality Assurance Inspector (QAI) or a Non-Destructive Testing (NDT) Inspector. This symbol indicates that a certain level of oversight or verification is required during maintenance activities to ensure that the standards of quality and safety are maintained.

The presence of this symbol suggests that the inspection must be thorough and is often focused on areas that require adherence to strict guidelines, typically involving critical components or systems where defects could lead to significant issues. The role of the QAI or NDT Inspector involves assessing and verifying the integrity of materials and workmanship, thereby providing assurance that the maintenance work meets all necessary regulatory and operational standards.

This emphasis on inspections by qualified personnel underscores the importance of having knowledgeable experts evaluate maintenance work to minimize risks and ensure the reliability of systems and equipment.