UPC Section 807 requires certain equipment, like a dishwasher, ice maker, or food-prep sink, to drain indirectly rather than being hard-piped to the sewer. The waste line ends above a receptor with an air gap or air break, so sewer water can never back up into food or clean equipment.
The Uniform Plumbing Code is published and copyrighted by IAPMO. This page explains the section in our own words with a short excerpt only. Read the full official text at the source.
Some things must never be directly connected to a sewer, because if the sewer backs up, the dirty water would flow straight into food, clean dishes, or drinking water. UPC Section 807 handles this with indirect waste. Instead of hard-piping the equipment to the drain, its waste line stops short and empties over an open receptor, with a gap of air in between that no backup can cross.
What this section says
The rule requires that certain fixtures and equipment drain indirectly, through an air gap or an air break, into a receptor that is itself properly trapped and connected to the drain. The code frames the protection this way:
An indirect waste pipe shall discharge into the building drainage system through an air gap or air break into a receptor.
The two methods differ slightly. An air gap is a full open space between the waste pipe outlet and the flood-level rim of the receptor, the strongest protection. An air break lets the waste pipe extend down into the receptor but not below the trap seal, so flow is still interrupted if the drain backs up. The code specifies which equipment needs which. Common items required to drain indirectly include a dishwasher, an ice maker, a food-prep sink, and the drain lines from water-treatment and refrigeration equipment. The receptor must be sized and placed so it can catch the discharge without splashing and stay accessible for cleaning.
When this comes into play
This section is central to commercial kitchens and shows up in homes too. Picture a restaurant ice machine: its drain cannot tie straight into the sewer, because a backup would push sewer water toward the ice. Section 807 requires that drain to end above a floor sink or receptor with an air gap, so the ice supply stays protected. In a house, the classic example is a dishwasher, whose drain must loop up high or pass through an air gap fitting so sink water cannot siphon back into it.
What this means for you
If you are installing a dishwasher, ice maker, or any food-related equipment, its drain has to be indirect, not hard-plumbed to the sewer. Getting this wrong is both a code violation and a real contamination risk. For a common commercial case where drainage backs up, see why a commercial kitchen drain keeps overflowing. The dishwasher air gap is the version most homeowners meet. This page covers the appliance side; for the piping rules and length limits, see UPC 803 indirect waste piping. A water-treatment or reverse-osmosis unit drains the same way, covered in UPC 611. Because the required method depends on the equipment, this is worth confirming with a licensed plumber during installation.
Full text and source
UPC Section 807 is part of the Uniform Plumbing Code. IAPMO publishes and holds the copyright on it. The excerpt above reflects the rule as adopted; Phoenix enforces the 2024 UPC with local amendments, so verify the current receptor and air-gap rules and section numbers. Read the indirect-waste rules on UpCodes, or confirm local amendments through the City of Phoenix: phoenix.gov/pdd.
Keep Reading
- UPC 1003: Which Fixture Traps Are Allowed (and Banned)
- UPC Section 1101: Storm Drainage and Roof Runoff
- UPC Section 603: Cross-Connection Control and Backflow Protection
- UPC 705: Joints and Connections in Drainage Piping
- Why does my commercial kitchen drain keep overflowing?
- What is a dishwasher air gap and do I need one?