Final answer:
A captain must accumulate at least 100 hours as PIC in the type of aircraft they are operating before the minimum MDA/DH and visibility standards can be adjusted to regular, provisional, or refueling airports.
Step-by-step explanation:
In accordance with [14 CFR 121], a captain must have served a minimum of 100 hours as Pilot in Command (PIC) in the specific type of aircraft they are operating. Until this threshold is met, the captain must adhere to certain minimums for Minimum Descent Altitude/Decision Height (MDA/DH) and visibility when conducting operations to regular, provisional, or refueling airports.
These minimums are determined by comparing the MDA/DH and visibility requirements for regular, provisional, and refueling airports, and selecting the higher of the two. This ensures that the captain operates under more stringent conditions until they have obtained sufficient experience in the specific aircraft type.
Please note that the exact values of the MDA/DH and visibility requirements will depend on the specific regulations outlined in [14 CFR 121] and may vary based on the specific airport and operational considerations.