What must inspection personnel be trained in according to Part 139 Subpart D?

Inspection personnel must be trained in airport inspection techniques according to Part 139 Subpart D because this regulation is focused on ensuring safe and effective operations at airports. Proper training in inspection techniques equips personnel with the necessary skills to identify potential safety hazards, assess compliance with safety regulations, and ensure that all airport facilities and operations adhere to required standards. This training is crucial for maintaining the overall safety of the airport environment, conducting effective evaluations of airport facilities, and ensuring that operational procedures are correctly followed. Understanding these inspection techniques allows for thorough and reliable evaluations essential for airport safety management.