Journeyman Plumber ExamPlumbing Code and RegulationsMedium
A journeyman plumber is installing a new commercial kitchen. The local plumbing code requires that all food preparation equipment with indirect waste connections, such as commercial dishwashers and steam kettles, must discharge into a floor sink with an adequate air gap. Which of the following is the PRIMARY reason for this code requirement?
- ATo ensure efficient drainage of wastewater.
- BTo facilitate easier maintenance and cleaning of the drain.
- CTo prevent cross-contamination of potable water.
- DTo prevent drain odors from entering the kitchen.
Show answer & explanationAnswer & explanation
Correct answer: C. To prevent cross-contamination of potable water.
The primary purpose of an air gap on indirect waste receptors for food preparation equipment is to prevent backflow of contaminated wastewater into the potable water supply, thereby preventing cross-contamination.
Why the other options are wrong
- A. Efficient drainage is a general requirement, but not the specific primary reason for an air gap.
- B. Easier maintenance is a potential benefit, but not the primary health and safety objective of the air gap.
- D. While a trap in the floor sink prevents odors, the air gap's primary role is not odor prevention.
Indirect Waste Air Gap Purpose
An air gap in an indirect waste system is a physical separation between the end of a waste pipe and the flood level rim of a receptor, designed to prevent backflow and cross-contamination.
- Prevents contaminated drain water from siphoning back into fixture or potable water supply.
- Required for fixtures with high contamination risk, like food service equipment.
- Ensures public health and safety by protecting potable water.
Memory trick: Keep clean water separate, like a moat for your castle.