Distribution box of sufficient size to accommodate the necessary field lateral lines shall be constructed at the head of each disposal field:
(A) Each field lateral line shall be connected separately to the distribution box and shall not be subdivided.
(B) The invert of all outlets shall be level, and the inlet invert shall be at least one inch above the outlets.
(C) If the level of the outlet inverts is less than 4 inches above the floor of the box, distribution baffles shall be provided. Note: If the level of the outlet inverts is from 4 to 6 inches above the floor of the box, permitting water retention to act in lieu of a baffle, the baffles will not be required. The level of the outlet inverts should not be more than 6 inches above the floor of the distribution box.
('66 Code, § 57-14)