(1) Except as specified in subsections (2), (3), and (4) of this section, a direct connection may not exist between the sewage system and a drain originating from equipment in which food, portable equipment, or utensils are placed.

(2) Subsection (1) of this section does not apply to floor drains that originate in refrigerated spaces that are constructed as an integral part of the building.

(3) If allowed by law, a warewashing machine may have a direct connection between its waste outlet and a floor drain when the machine is located within five feet (1.5 mm) of a trapped floor drain and the machine outlet is connected to the inlet side of a properly vented floor drain trap.

(4) If allowed by law, a warewashing sink may have a direct connection.