Does California Code Require An Air Gap In Kitchen Sink​?

Many people confused that “Are air gaps required in California?”. Here is the answer:

Yes, California’s Health and Safety Code (HSC) requires an air gap between the water supply inlet and the flood level rim of a plumbing fixture. The air gap must be at least one inch and at least twice the diameter of the water supply inlet. 

An air gap prevents contaminated water from backing up into the water supply through the dishwasher. It’s a proven method to prevent backflow and contamination, and it works in every circumstance. 

Even if your state doesn’t require an air gap, it’s a good idea to install one to ensure proper hygiene.

A kitchen sink air gap is a vertical space between the sink and the end of the faucet or pipe that prevents contaminated water from entering the clean water supply

About	What it does
Purpose	Prevents contaminated water from entering the clean water supply
Location	Usually to the side of the sink, at the top corner near the dishwasher
Appearance	Short, squaw cylinder that may have open valves on one or both sides
Importance	Backflow of contaminated water can cause serious health risks

Some people may bypass the air gap requirement by installing a “High Loop” under the sink. A High Loop works when the dishwasher drain line is attached to the underside of the sink or countertop.

Where To Install Air Gap In Kitchen Sink?

In a kitchen sink, the air gap is typically installed on the countertop, close to the sink’s rim, and near the faucet, ensuring that any water draining through the air gap flows directly into the sink instead of onto the counter. 

• Location: On the countertop, close to the sink’s edge. 
• Purpose: Prevents backflow of dirty water from the dishwasher drain into the clean water supply. 
• Connection: The air gap connects to the dishwasher drain hose. 
• Pre-cut hole: Most sinks have a pre-cut hole for the air gap, but if not, you may need to drill one. 

How Big Should Air Gap In Kitchen Sink?

A standard air gap in a kitchen sink should be at least 1 inch in size, which is the minimum required to prevent backflow of water from the drain into the water supply line; most plumbing codes specify this as the standard size. 

• Function: An air gap creates a vertical space between the faucet and the sink, preventing wastewater from siphoning back into the water supply line if the water pressure drops. 
• Location: Typically, the air gap is located on the countertop near the sink, often connected to the dishwasher drain hose. 
• Size considerations: While 1 inch is the standard, specific plumbing codes may have slightly different requirements depending on the faucet size. 

An air gap in a kitchen sink, usually found on the dishwasher drain connection, is important because it prevents contaminated water from flowing back into the clean water supply, thus protecting against potential health risks by stopping “backflow” which can occur when negative pressure builds up in the plumbing system; essentially, it creates a physical barrier between dirty wastewater and the clean water source.