2003 Code Definition for an Agricultural Building:

A structure designed and constructed to house farm implements, hay, grain, poultry, livestock or other horticultural products.  This structure shall not be a place of human habitation or a place of employment where agricultural products are processed, treated, or packaged, nor shall it be a place used by the public.  Excluded from the definition of agricultural building are structures enclosing indoor riding arenas with an occupant load of 10 or more.

(Section R202a.IRC)  (Resolution 2004-86 & 2004-101)