Final answer:
The question pertains to the duration that training records, tests, and scores must be retained by the Naval Aircraft NDI Technician school and FRCs. An exact timeframe cannot be given without the specific source document, but military and technical records are typically kept for several years.
Step-by-step explanation:
The subject of this question is related to the procedural protocols for record-keeping in a specific context of military training, which in this case is the Naval Aircraft Non-Destructive Inspection (NDI) Technician school and Fleet Readiness Centers (FRCs). The query revolves around the duration for which certain types of records must be retained. These records pertain to training materials utilized, exams conducted, and the scores individuals obtained in those tests. While the question seems to request an exact numerical value for how many years the records must be kept, without the source document that specifies this requirement, an exact answer cannot be provided here. However, it's common for various institutions, especially within the military and related to certifications and qualifications, to maintain records for substantial periods, often ranging from a few years to indefinitely, depending on the nature and significance of the records.