Louisiana Administrative Code
Title 51 - PUBLIC HEALTH-SANITARY CODE
Part XIV - Plumbing
Chapter 8 - Indirect and Special Wastes
Section XIV-805 - Indirect Waste Methods

A. Air gap (drainage system). The air gap (drainage system) between the indirect waste and the building drainage system shall be at least twice the diameter of the effective opening of the indirect waste pipe, but in no case less than 2 inches (51 mm), and shall be provided by extending the indirect waste pipe to an open, accessible floor sink, service sink, floor drain, hub drain or other suitable fixture which is properly trapped and vented. The indirect waste pipe shall terminate a sufficient distance above the flood-level rim of the sink or receptor to provide the minimum required air gap and shall be installed in accordance with other applicable Sections of this code.

B. Air break (drainage system). The air break (drainage system) between the indirect waste and the building drainage system shall be installed such that the level of the lowest outlet located on the fixture, device, appliance or apparatus (to which the indirect waste pipe connects) is above the flood-level rim of the receiving sink or other receptor by a vertical distance of at least twice the diameter of the effective opening of the indirect waste pipe, but in no case less than 2 inches (51 mm). In addition, the indirect waste pipe shall terminate below the flood-level rim of the receiving sink or other receptor a distance equal to not more than one-half (1/2) the diameter of the effective opening of the indirect waste pipe.