Any use which complies with all of the following conditions may be operated as an accessory use:
A. 
Is clearly incidental and customary to and commonly associated with the operation of the permitted uses.
B. 
Is operated and maintained under the same ownership and on the same lot or contiguous lot to the permitted uses.
C. 
Does not include structures or structural features inconsistent with permitted uses.
D. 
Does not include residential occupancy, except for living quarters for farm, domestic or other employees having employment on the premises.
E. 
Accessory buildings, other than farm buildings, shall be located only in the rear yard.
F. 
If an accessory use is carried on within the structure containing the permitted uses, the gross floor area within such structure utilized by accessory uses, except garages and off-street loading facilities, shall be not greater than 20% of the gross floor area, but not to exceed 300 square feet, of a single unit dwelling or 10% of the gross floor area of a structure containing any permitted uses other than a single unit dwelling.
G. 
Fallout shelters are permitted as accessory uses and structures in any district, subject to the yard and lot coverage regulations of the district. Such shelters may contain or be contained in other structures or may be constructed separately and, in addition to shelter use, may be used for any accessory use permitted in the district, subject to the district regulations on such use. Fallout shelters constructed completely below the ground level, except for a vent not exceeding 30 inches in height above ground level, may be contained within any yard area.