((a)) Under regulations prescribed by the Secretary of the Navy appropriated funds may be used to pay the cost of installation and use, other than for personal long distance calls, of extension telephones connecting public quarters occupied by personnel in the following categories with the switchboards of their official stations:

((1)) Members of the naval service.

((2)) Members of the Coast Guard when it is operating as a service in the Navy.

((3)) Members of the National Oceanic and Atmospheric Administration serving with the Navy.

((b)) The Secretary, to the extent he considers proper, may delegate the authority conferred by this section, except the authority to prescribe regulations, to any person in the Department of the Navy, with or without the authority to make successive redelegations.