The Manager is hereby authorized to permit the following exceptions in the restricted parking zone:
(a) To provide available space for the loading and unloading of commercial vehicles, for bus stops or for other uses of a similar nature;
(b) To limit parking to 15 minutes for one designated space in front of any commercial establishment, bank, private office or governmental building within the restricted zone, upon the application of the owner or manager of such establishment, bank, office or building and upon the posting of proper signs indicating the 15-minute restriction; and
(c) To temporarily suspend any of these provisions in the case of an emergency and to adopt and enforce any temporary traffic regulation as conditions during the emergency may require.