Health codes generally require different sinks for different jobs, and using the wrong one is a common violation. A typical kitchen has a three-compartment sink for warewashing, one or more dedicated hand-washing sinks, a separate prep sink for washing produce and thawing, and a mop (service) sink for cleaning water. You cannot legally substitute one for another — you can't wash hands in the prep sink or rinse mops in the dish sink. Confirm exact requirements with your local health department; this guide explains how to choose each type.
| Sink | Purpose | Notes |
|---|---|---|
| 3-compartment | Manual wash, rinse, sanitize of wares | Usually required even with a dish machine |
| Hand sink | Handwashing only | Must be dedicated, accessible, and stocked with soap and towels |
| Prep sink | Washing produce, thawing, food prep | Often required to be separate from warewashing |
| Mop / service sink | Filling and dumping cleaning water | Keeps dirty water away from food areas |
The three-compartment sink exists to run the manual warewashing sequence: wash in hot detergent water, rinse in clean water, and sanitize in a chemical or hot-water solution, then air dry. Each step needs its own bowl, which is why two compartments will not pass. Size the compartments to your largest regularly used item — sheet pans, stock pots, or cambros must fully submerge in a single compartment. If your biggest pot doesn't fit, you cannot properly wash it, so measure before you buy. Common bowl sizes step up from roughly 10x14 inches for light use to 24x24 inches and larger for heavy pot washing.
Tip: For hot-water sanitizing the final rinse is typically very hot (around 171°F at the sink), while chemical sanitizing follows the sanitizer's label concentration and contact time. Post your procedure at the sink — inspectors look for it.
Drainboards are the flat landing areas on one or both ends of the sink. They give you a place for soiled wares before washing and clean wares to drip-dry after sanitizing, and many codes require adequate drainboard or shelf space. An integrated drainboard is one continuous welded piece — more sanitary and sturdier than a bolt-on. Choose left, right, or double based on your workflow and the direction dishes travel.
Get a faucet with enough reach and height (a swing spout or pre-rinse unit) to serve every compartment. Favor a 300-series stainless steel bowl for corrosion resistance, and confirm NSF certification. Pay attention to bowl depth as well: deeper compartments (10–14 inches) let you submerge tall pots without water sloshing over the divider.
Plan the drain and plumbing before install, too. Many jurisdictions require food-prep and warewashing sinks to drain indirectly through an air gap to the floor sink rather than connecting straight to the sewer line, which prevents backflow into food areas. Confirm how many hand sinks your layout needs — codes often tie the count to the number of prep areas and their distance from staff. Pair the sink with a drip-drying stainless work table and clean-drying shelving nearby. For the full picture of what your kitchen must include, see required commercial kitchen equipment and the requirements section.