How to Use a 3-Compartment Sink: Methods, Steps, and Tips – FoodSafePal® (2024)

A dishwasher makes washing and sanitizing dishes a heck of a lot easier than washing and sanitizing by hand.

However, not every food service establishment or business has a dishwasher, and even in places that do have a dishwasher, it may be broken or items may be too big to fit in it.

In these instances, you must rely on a 3-compartment sink to properly wash and sanitize dishes.

This article explains how to use a 3-compartment sink, discussing the steps you must take to properly wash, rinse, and sanitize.

Three-compartment sink order

Except in certain instances, all food establishments and businesses — including food trucks — must have a 3-compartment sink to manually wash, rinse, and sanitize food equipment, dishes, utensils, and removable parts from equipment like ice machines.

As the name suggests, a 3-compartment sink has three compartments, each for different use.

These compartments must be large enough to immerse the largest cooking equipment or utensils in your operation unless you have a dishwashing machine that can accommodate them.

The three compartments should be used for washing, rinsing, and sanitizing.

Here are the three-compartment sink steps:

Wash

The first compartment — either from the left or right side, depending on how the sink is labeled —is intended for washing.

Before you get started, wash your hands, and clean and sanitize each compartment.

Then, fill the compartment with hot water that is at least 110ºF (43ºC) and add soap or detergent (1).

Use a calibrated thermometer to ensure the water reaches and maintains this temperature.

Hot water helps loosen and dissolve grease and other food contaminants while also allowing the soap or detergent to work more effectively.

However, you still need to rinse and scrape off as much food as you can before placing them in the wash compartment. This will keep the water cleaner and allow the soap or detergent to do its job.

You can use a scrub brush or dishcloth to remove any remaining food particles or debris.

Rinse

After washing, move the dishware into the second compartment for rinsing.

The second compartment should contain water only — no soap or detergent.

The temperature of the water you use for rinsing should be warm or around the same temperature as the wash water.

Rinsing helps remove soap or detergent residue and any food particles that may still be present.

Drain and refill the compartment with water often and as it becomes cloudy or murky.

Sanitize

Sanitizing is ultimately what kills pathogens or reduces them to safe levels, so this step is very important.

There are two ways to sanitize dishware using a 3-compartment sink —by heat or a chemical sanitizing solution.

If you use heat, the temperature of the water needs to be at 171ºF (77ºC) or above and you must keep the dishware immersed for at least 30 seconds (1).

This temperature is more than hot enough to severely burn you so if you use this method of sanitation, you must use a rack or basket that allows you to fully immerse and remove dishware from the hot water without touching it.

This temperature is also much hotter than what a traditional water heater can produce so a heat booster is needed to bring the water to temperature and maintain it.

Chemical sanitization uses chlorine, iodine, quaternary ammonium, or other approved solution to kill pathogens (1).

Their effectiveness is primarily influenced by the concentration and pH of the sanitizer solution.

Therefore, you must follow the manufacturer’s directions for use with chemical sanitizers and use a test kit to ensure the correct concentration.

Not using enough sanitizer can make the solution weak and ineffective while using too much can make the solution too strong and unsafe.

After you have sanitized the dishware — whether with heat or a chemical solution —let it air dry completely before putting it away. Never use a cloth or towel to dry dishes as this can recontaminate them.

Putting dishes away while they are still wet —known as wet nesting or stacking —creates a moist environment that encourages the growth of bacteria.

Use the drainboard or landing surface located after the sanitizing compartment of the 3-compartment sink to air dry the dishes.

3-compartment sink steps and tips for safe use

Here’s a quick look at the steps to properly wash and sanitize dishes in a 3-compartment sink:

1. Scrape: Scrape off or rinse away any leftover food on the dishes.
2. Wash: In the first sink, use warm (110ºF / 43ºC), soapy water, and a brush to remove oil and other food particles from the dishes.
3. Rinse: Move the dishes to the second sink and rinse them with clean, warm water to remove leftover soap or detergent.
4. Sanitize: Move the dishes to the third sink and soak them in your chosen chemical sanitizer according to the manufacturer’s direction. Alternatively, immerse dishes in very hot water (171ºF / 77ºC) for 30 seconds.
5. Air dry: Move the dishes to the drainboard or a nearby drying rack and allow them to air-dry completely (never towel dry) before using or putting them away.

You must follow these steps in order to ensure the dishes are free from food hazards that can make people sick. Skipping any step can make the entire process ineffective and increase the risk of foodborne illnesses.

Tips for using a 3-compartment sink safely

You cannot use a 3-compartment sink to wash your hands or dispose of chemicals or mop water.

While on the topic of hand hygiene, remember that you must wash your hands between handling dirty and clean dishes.

If you drop dirty dishes into the wash compartment and then put away clean dishes without washing your hands, those dishes are no longer clean and they must be washed, rinsed, and sanitized again.

You can wash produce or thaw food in a 3-compartment sink as long as you clean and sanitize it before and after each time and the sink is designated for these activities.

To ensure you understand how to use a 3-compartment sink safely, you may need to earn your food handler card as a dishwasher.

The bottom line

Except in certain instances, all food service establishments must have a 3-compartment sink to wash, rinse, and sanitize dishware and food equipment.

Maintain the wash water at 110ºF (43ºC) or higher, and the rinse water at a similar temperature.

If using heat as the sanitizing method, you must immerse dishware in hot water that is 171ºF (77ºC) or higher for at least 30 seconds.

Alternatively, you can use chlorine, iodine, quaternary ammonium, or another approved solution as a sanitizing method to kill pathogens.