Answers to common questions about food-prep sinks and the utility, service, and mop sinks a commercial kitchen needs. Because sink requirements are set by health and plumbing code, treat these as general guidance and confirm the specifics for your fixtures with your local health department and plumbing inspector before you build.
A kitchen prep sink is a dedicated sink used for food preparation, washing produce, thawing under running water, portioning, and rinsing, kept separate from warewashing and handwashing sinks. It is often a single- or two-compartment stainless sink in the prep area, and in many jurisdictions it must drain indirectly through an air gap into a floor sink because it is a food-contact fixture. Keeping food prep in its own sink helps prevent cross-contamination. Confirm requirements with your local health code.
A food preparation sink, or food-prep sink, is the same thing as a prep sink: a sink designated only for handling food, such as washing fruits and vegetables, rinsing raw proteins, or thawing. It should not be used for handwashing or for washing dishes, since those tasks belong to a hand sink and the warewashing sinks. Because food touches it, it typically requires an indirect air-gap drain to protect against backflow. Check your health department's rules for prep-sink drainage.
A prep sink is used for food-prep tasks: rinsing and soaking produce, thawing food under cold running water, draining and portioning ingredients, and rinsing rice or beans. Keeping these tasks in a separate sink prevents cross-contamination with dirty dishes or hands. It is not for handwashing, mopping, or warewashing. Some operations add a second compartment or a disposer for high-volume produce work. What counts as required prep-sink use varies, so verify with your local health code.
For most kitchens that handle fresh produce or raw proteins, yes. A dedicated prep sink keeps food prep separate from dish and hand sinks, which reduces cross-contamination risk and is often expected or required by inspectors. It also speeds workflow, since staff aren't competing for the warewashing or hand sink. Very small operations with minimal prep may get by without one, but if you wash produce or thaw regularly, a prep sink pays off. Check whether your local code requires one.
Usually not on its own, because a prep sink handles produce rinse water and food particles rather than the greasy wastewater from cooking and dishwashing. Many codes route only grease-bearing fixtures, like the three-compartment sink, dish machine, and mop sink, through the grease interceptor. However, requirements vary by jurisdiction, and some require most kitchen drains to pass through the trap. Confirm with your local plumbing and health authority which fixtures must connect to the grease interceptor.
In most jurisdictions, yes. Because a prep sink is a food-contact fixture, its drain typically must discharge indirectly, through an air gap into a floor sink or funnel drain, so contaminated water can never siphon back into the sink. This is the same indirect-drain principle applied to many food-service fixtures. The exact air-gap distance and floor-sink requirement are set by plumbing code. Verify the required drain configuration with your local plumbing inspector before installation.
Size the prep sink to your largest task. A single bowl around 16 by 20 inches and 12 to 14 inches deep handles most produce washing and thawing, while high-volume kitchens use larger or two-compartment prep sinks. The bowl should be deep enough to submerge your biggest pans or produce batches without splashing. Leave adjacent drainboard space for draining. Match the sink to your prep volume and the space available, and confirm any minimum size requirements with local code.
Prep sink bowls are commonly about 10 to 14 inches deep, deep enough to soak and rinse produce or thaw items under running water without splashing. Some heavy-duty models go deeper. Depth matters more than footprint for prep work, since you want to submerge batches and large pans. Pair the depth with a gooseneck or high-arc faucet so you have clearance to fill and rinse. Check the interior bowl depth on the spec sheet rather than overall height.
Choose a faucet that clears the bowl depth and reaches the whole basin. A tall gooseneck, or high-arc, faucet is popular for prep sinks because it leaves room to wash produce and fill tall pots. Match the faucet's mount, deck or wall, and spread to the sink's pre-drilled holes, and pick a spout long enough to reach both bowls of a two-compartment sink if applicable. Commercial faucets should be durable, easy to clean, and, where required, meet backflow-protection rules.
A food-prep sink is usually a stainless-steel basin, one or two compartments, mounted on a stainless table or cabinet, often with an integral drainboard and a tall faucet. It looks similar to other commercial sinks but is placed in the prep area and labeled or understood as food-only. Many are freestanding on legs with an indirect waste that drops to a floor sink below. The stainless construction is smooth and non-porous so it cleans and sanitizes easily.
A bar prep sink is a small sink at the bar used for food-related prep like cutting and rinsing garnishes, fruit, and mixers, separate from the bar's glass-washing sinks and hand sink. Bars often have several sinks: a three- or four-compartment sink for glasses, a dedicated hand sink, and a prep sink for garnishes. Keeping garnish prep in its own sink supports food safety at the bar. Local code sets which sinks a bar must have, so verify requirements.
A two-compartment sink has two bowls and is used for tasks that need a wash-and-rinse pair or for food prep, and in some jurisdictions for warewashing of certain items. It is not a substitute for a three-compartment sink where three-step wash, rinse, and sanitize warewashing is required. Bars and prep areas commonly use two-compartment sinks. Whether one is acceptable for your intended use depends entirely on local health code, so confirm before relying on it for dish sanitizing.
A utility sink is a deep, rugged sink for general non-food tasks, filling and emptying buckets, rinsing tools and equipment, and cleaning jobs that would foul a food or hand sink. In commercial settings the term often overlaps with a service sink or mop sink. Utility sinks are typically deep-basin stainless or molded units. Keeping heavy cleaning tasks in a utility sink protects food-prep and warewashing sinks from contamination. Check which specific cleaning sinks your local code requires.
Utility and service sinks come in a range of sizes. Molded floor-mount mop basins are commonly about 24 by 24 inches or 24 by 36 inches with a 10- to 12-inch-deep basin. Wall-hung or freestanding stainless utility sinks run roughly 18 to 36 inches wide with deep single bowls, and multi-bowl utility sinks are wider. Choose one large enough to fit your mop bucket or the containers you rinse. Leave clearance for the faucet and hose, and confirm any code-required dimensions locally.
A utility sink pump, a drain or sump pump, lifts wastewater from a utility or mop sink up to the drain line when the sink sits below or too far from the building's gravity drain, such as in a basement. Water collects in a basin and the pump discharges it when it reaches a set level. Commercial installations must still meet backflow and indirect-waste rules. If you need one, size it to the flow and verify the setup with a licensed plumber and local code.
A floor-mount mop basin sets on the finished floor over a trapped, vented drain, with a wall-mounted faucet that has an integral vacuum breaker (backflow protection) and a hose thread. A wall-hung utility sink is anchored to the wall and connected to hot and cold supply and a trapped drain. Add a mop hanger and bumper guards, and position it near cleaning-supply storage. This is licensed plumbing work; confirm the drain, vent, and backflow requirements with local plumbing code.
In a restaurant, the service sink, or mop sink, is used to fill and empty mop buckets, rinse cleaning tools, and dispose of dirty mop water, keeping that contamination out of food and hand sinks. It usually has hot and cold water with a hose thread and a backflow-protected faucet. Locating it near the cleaning-supply storage keeps janitorial work contained. Health and plumbing codes typically require a service or mop sink, so verify what your jurisdiction mandates.
A molded floor-mount mop basin runs about $150 to $400, and a stainless service or utility sink roughly $200 to $700 depending on size and gauge. A faucet with vacuum breaker, hose, and mop hanger adds $100 to $300. Installation, plumbing the supply and a properly trapped and vented drain, is usually the larger cost and depends on your layout. Buy a durable basin and a backflow-protected faucet, and confirm the drain and vent meet local plumbing code.
The mop basin itself runs about $150 to $400, and installation, tying into a trapped and vented drain and running hot and cold supply with a backflow-protected faucet, typically adds a few hundred to over a thousand dollars depending on how far the plumbing must run. Setting one into an existing slab costs more because the floor may need cutting and patching. New construction is cheaper since it is roughed in before finishes. Get a plumber's quote and verify code.
Pick a basin big enough to fit your mop bucket and deep enough to prevent splashing, in a durable material, molded composite for floor mop basins or stainless for wall-hung utility sinks. Add a faucet with an integral vacuum breaker for backflow protection and a hose thread, plus a mop hanger and bumper guards. Site it near cleaning-supply storage with a properly trapped, vented, code-compliant drain. Match hot- and cold-water supply to the faucet, and confirm the install meets local code.
Use the prep sink only for food tasks, washing produce, thawing under cold running water, and rinsing ingredients, and never for handwashing, warewashing, or mop water. Clean and sanitize it before and after each use and between raw and ready-to-eat foods to prevent cross-contamination. Make sure it drains indirectly through its air gap so nothing backs up into the bowl. Keep a separate hand sink stocked nearby so staff aren't tempted to wash hands in it. Follow local health code.
It depends on type. Individual bowls on a commercial sink are commonly around 16 to 24 inches wide and long, and a three-compartment sink with drainboards can run 6 to 10 feet overall. Prep and bar sinks are smaller, while pot sinks have large, deep bowls for sheet pans and stockpots. Size the bowls to your biggest pans and your volume, and allow drainboard space on each end. Confirm any minimum compartment sizes for warewashing with local code.
Compartment depth varies by use. Prep and bar sink bowls are often about 10 to 14 inches deep, while warewashing and pot sinks are deeper, roughly 12 to 16 inches, so you can fully submerge large pans for washing, rinsing, and sanitizing. Deeper bowls reduce splashing and let you soak sheet pans. Match depth to your largest cookware, and pair it with a tall faucet for clearance. Check the interior bowl depth on the spec sheet rather than the overall height.
Commercial sinks are typically built so the rim, or the work surface, sits about 34 to 36 inches off the floor, comfortable for standing work and consistent with most commercial cabinetry and worktables. Floor-mounted units on adjustable legs let you fine-tune height and level the sink. Hand sinks and ADA-accessible fixtures follow their own mounting-height rules. Set the height for your staff's comfort where possible, and confirm any accessibility or code-required dimensions locally.
Width depends on the number of bowls and drainboards. A single-bowl prep or bar sink may be about 18 to 30 inches wide, while a three-compartment sink with left and right drainboards commonly spans 6 to 10 feet or more. Pot sinks and four-compartment bar sinks are wider still. Measure your available wall run and include the drainboards, which you need for scraping incoming items and air-drying clean ones. Confirm required compartment and drainboard sizes with local code.
A single-bowl prep or bar sink runs roughly $150 to $600, a stainless three-compartment sink with drainboards about $400 to $1,500 depending on size and gauge, and large pot sinks more. Faucets, pre-rinse sprayers, and drain fittings add $100 to $500. Installation, supply lines and a trapped, vented, air-gapped drain, is often the larger cost and depends on your layout. Buy a heavier stainless gauge for durability, and confirm drainage requirements with local code.
Each bowl gets hot and cold supply to the faucet and a drain, and food-service and warewashing sinks generally must discharge indirectly, through an air gap, into a floor sink so waste can't back-siphon into the bowl. Grease-bearing sinks may need to route through the grease interceptor. Drains must be trapped and vented per code, and some sinks share a common waste with individual traps. This is licensed plumbing work; confirm air-gap, trap, vent, and grease requirements with local code.
Wash the sink with hot water and a mild detergent, rinse, then sanitize with an approved food-contact sanitizer at the correct concentration and let it air-dry. Wipe with the grain of the steel to avoid scratches, and use non-abrasive pads. For mineral scale or water spots, a deliming or stainless-safe descaler works; for stains, a stainless cleaner restores the finish. Avoid steel wool and chlorine left in contact, which can pit the metal. Clean and sanitize food-prep sinks between uses.