Sanitation Practices


Adapted from: National Food Service Management Institute. (2009). Serving it safe. University, MS: Author.


Table of Contents


Personal Hygiene/Food Handling Practices

Operating a Food-Safe Facility

Sanitation Practices

Insect & Rodent Control

Smallware & Equipment Sanitation




Food Safety is Everyone’s Responsibility


A safe environment for commercial food preparation and service requires that every employee be committed to high standards of sanitation.



Manager’s Responsibilities


Know requirements for maintaining a sanitary operation.

  • Use a daily, weekly, and monthly cleaning schedule to assign
    routine cleaning tasks.
  • Establish standard procedures for cleaning specific areas of the
    foodservice facility such as the restroom, storeroom, refrigerators
    and freezers, preparation area, dining area, and service line.
  • Teach and coach employees on how to maintain a sanitary
    foodservice operation, utilizing best practices.
  • Hold employees responsible for cleaning and sanitizing assigned
    areas using the pre-established procedures.
  • Have routine inspections to ensure that sanitation standards are
    met. Use the Food Safety Checklist in the “Links” list below, or an
    inspection form developed specifically for your operation.
  • Take pride in operating a clean and sanitary foodservice facility.


Employees’ Responsibilities


  • Follow standard procedures for cleaning and sanitizing specific areas of the facility.
  • Ask the manager for help as needed to know how to properly clean and sanitize assigned areas.
  • Take pride in the important role you play in maintaining a food-safe operation.


Personal Hygiene/Food Handling Practices


Every person who works in a foodservice operation is responsible for having good personal hygiene and clean work attire. This applies to the manager, cooks, servers, dishwashers, and cashiers. Full-time and part-time employees are equally responsible for food safety.


Bacteria are present on and in human bodies—hands, hair, throat, and intestines. They are also on clothing and on common items that are handled regularly, such as money, pens, and pencils. The simple act of patting one’s hair or rubbing one’s ear can contaminate hands with staphylococci bacteria. If not washed, hands can contaminate a food and cause foodborne illness. Anyone can contaminate food with a harmful microorganism and not even know it! The personal hygiene, attire, and general health habits of foodservice employees play a crucial role in keeping harmful microorganisms away from the food.


Personal Sources of Food Contamination


Food contamination from hands can occur:

  • after touching anything that could contaminate hands
  • by being sick with a stomach or intestinal illness that includes vomiting and/or diarrhea or other symptoms
  • after caring for a person with a stomach or intestinal illness
  • by having an uncovered infected burn, wound, or other injury
  • when taking prescribed or over-the-counter medicines (the medicine can get into the food or on hands)


A person who feels completely healthy may be the host of a harmful microorganism and not know it. Some foodborne illnesses do not cause symptoms until the most infectious stage has passed (Hepatitis A). Some harmful organisms remain in a person’s body after the symptoms have disappeared (Salmonella bacteria).


Sickness can lead to contaminated food – foodservice employees should not work with or be around food if they have any of the following symptoms: fever; diarrhea; vomiting; sore throat; jaundice (yellow skin and eyes); or persistent sneezing, coughing, or runny nose. The Food Code explains that the foodservice manager must exclude from the establishment any foodservice employee who has been diagnosed with illness due to Salmonella Typhi, Shigella spp., Shiga toxin-producing E. coli, or Hepatitis A virus, and must notify the local regulatory agency. Employees may return when they are no longer contagious. Follow state and local regulations regarding when employees may return to work.


Use Guidelines for Good Personal Hygiene


Food handlers must have the highest standards of personal hygiene because they have the potential of making many people sick when their standards are lowered.


  • Wash hands properly, frequently, and at appropriate times.
  • Wash hands before putting on single-use gloves. Change gloves frequently.
  • Avoid bare-hand contact with ready-to-eat food.
  • Keep fingernails trimmed, filed, and maintained so the edges and surfaces are cleanable and not rough. Best practice is not to wear fingernail polish or artificial fingernails.
  • Keep hair and body clean. Bathe every day.
  • Maintain good health.
  • Treat and bandage wounds and sores. When hands are bandaged, single-use gloves must be worn at all times to protect the bandage and to keep it from falling into food.
  • When feeling ill, alert management and avoid working with food.


Observe Proper Handwashing Procedures


Washing hands correctly and frequently is one of the most important ways that foodservice employees can promote food safety. 


When to wash hands


Wash hands whenever hands are soiled and before

  • beginning food preparation
  • putting on disposable gloves
  • serving customers


Wash hands after


  • arriving at work and after breaks
  • using the restroom and then again at the kitchen hand washing sink
  • eating, drinking, smoking, or chewing tobacco or gum
  • using the telephone
  • using a handkerchief or a tissue
  • handling inventory
  • handling raw food
  • touching or scratching areas of the body, such as ears, mouth, nose, or hair
  • coughing or sneezing
  • clearing or cleaning tables
  • clearing, scraping, or washing dirty plates or utensils
  • handling garbage
  • handling money on the cafeteria line
  • touching dirty aprons, clothing, or dirty surfaces
  • using cleaning chemicals


Remember to post appropriate hand washing signs as required by state and local public health departments.


How to wash hands


  • Use the hand washing sink with running water at approximately 100 °F and liquid soap.
  • Lather hands and exposed arms.
  • Rub hands together for at least 20 seconds.*
  • Wash hands thoroughly, paying close attention to fingernails.
  • Rinse in clean, running water.
  • Dry hands using a paper towel or air dryer, not a cloth or apron.
  • Turn off the faucet with the paper towels used to dry your hands.


*An easy way to determine if hands are rubbed and lathered for 20 seconds is to sing one verse of “Old MacDonald.”


Single-Use Gloves


Increasing emphasis is being placed on the importance of avoiding bare-hand contact with ready-to-eat food. By using single-use gloves on clean hands, a barrier is placed between the foodservice employee and the food. Gloves are only one kind of barrier. Others include tongs and deli paper. Follow the regulations of the state and local public health department.


How to use single-use gloves correctly


  • Wash and dry hands.
  • Put on clean gloves.
  • Use the gloves as if they are a serving utensil.
  • Change gloves if they become torn or soiled or if you begin working with a different food.
  • Never wash and reuse gloves.


Proper Attire for Food Safety


An important part of good personal hygiene is clean and appropriate dress. Every foodservice employee should wear a uniform made of a material that can withstand hot water during laundering.


  • Wear a clean, appropriate uniform every day. Change uniforms as often as necessary to prevent bacteria on soiled clothing from spreading to the hands and then to food.
  • Wear a clean apron when preparing food and take it off when leaving the food preparation area. An apron should be removed to go on break, eat lunch, smoke, or use the restroom.
  • Change an apron if it becomes soiled.
  • Avoid wearing jewelry other than a plain ring, such as a wedding band, when preparing or serving food. For the use of medical information jewelry, follow the recommendations from the state or local public health department.
  • Wear a hair restraint to keep hair and particles in the hair from falling into food.
  • Wear comfortable, low-heeled, closed-toe shoes with soles that prevent slipping and injury.


Use Common Sense as a Guide When Working With Food


  • Know when and how to wash hands. Avoid using a food preparation sink or a three compartment sink to wash hands.
  • Taste food the correct way. Place a small amount of food from the food container into a small bowl. Step away from the food container. Taste the food with a teaspoon. Remove the used bowl and teaspoon to the dish room. Never reuse a bowl or spoon already used for tasting. Wash hands immediately after tasting.
  • Never taste a food that includes a raw ingredient of animal origin. For example, never taste cookie dough that includes raw eggs.
  • Do not eat, smoke, use tobacco, or chew gum when preparing foods.
  • When feeling ill, alert the foodservice manager and avoid working with food.
  • Do not work with food when experiencing nausea, vomiting, diarrhea, fever, sore throat, or jaundice (yellow skin and eyes), or after caring for someone at home with those symptoms.
  • Do not work with food after being diagnosed with a foodborne illness until no longer contagious.


Operating a Food-Safe Facility


A food-safe facility starts by being clean and in good repair. The entire facility, including both work areas and equipment, should be designed for easy cleaning and maintenance.


It is important to eliminate hard-to-clean work areas and faulty or overloaded refrigerators or other equipment. Also, get rid of dirty surroundings and any conditions that will attract bugs or other pests. Remember, the easier the workplace is to clean, the more likely it will stay that way.


Know the Characteristics of a Food-Safe Facility


Food-safe facilities are designed for easy cleaning and maintenance. The workflow prevents clean and soiled items from crossing paths during food production and service.


  • Floors, walls, and ceilings are free of dirt, litter, and moisture.
  • The service line and serving stations are clean and neat.
  • Exhaust fans and hoods are clean and operating properly.
  • All types of storage areas, such as the dry storage room, the refrigerators, and the freezers, are in excellent condition. There is no damage or spoilage, no broken or torn packages, and no bulging or leaking cans. Floors are clean, dry, and uncluttered.
  • Cleaning supplies and chemicals are stored away from food supply areas. Measuring utensils used for chemicals are stored with the chemical and are never used with or near food.
  • Restrooms are convenient, clean, adequately stocked with soap and paper towels, and have warm running water.
  • Garbage is kept away from food preparation areas.
  • Garbage containers are leak-proof, waterproof, pest-proof, durable, easy to clean and sanitize, and have tight-fitting lids.
  • Spills are cleaned immediately.
  • Garbage is disposed of properly and promptly.
  • There is no evidence of infestation from bugs or other pests.


A food-safe facility has scheduled procedures for cleaning and maintaining:


  • floors, walls, and ceilings
  • service lines and dispensers
  • ventilation
  • restrooms
  • trash collection areas


Sanitation Practices


Maintain Clean Floors, Walls, and Ceilings


Establish routine cleaning procedures for walls, floors, and ceilings. The facility should be free of dirt, litter, and moisture. Corners and hard-to-reach places should also be cleaned routinely.


  • Clean walls around food preparation and cooking areas daily with a cleaning solution or by spraying with a pressure nozzle.
  • Sweep or vacuum floors daily, then clean them using a spray method or by mopping. Mark the area being cleaned with signs or safety cones to prevent an accident. Avoid creating dust or water splashes during food preparation times. Set aside a routine cleaning time after the main hours of food preparation. Spills should be cleaned immediately.
  • Swab ceilings, instead of spraying them, to avoid soaking lights and ceiling fans. Clean light fixtures with a sponge or cloth. Establish a routine cleaning schedule based on the needs of the foodservice.


Maintain a Clean and Sanitary Service Line and Serving Stations


Establish a routine daily cleaning schedule for the service lines and serving stations.


  • Assign an employee to set up and maintain each service line or serving station for each meal service.
  • Clean and sanitize the hot and cold wells of the service line after every meal.
  • Clean and sanitize dispensers, such as beverage dispensers or coffee machines after every use. Follow equipment cleaning guidelines.
  • Clean and sanitize milk coolers. Follow equipment cleaning guidelines.
  • Clean up spills immediately.


Maintain Clean Employee Restrooms


Restrooms should be convenient, sanitary, and adequately stocked with the following:


  • warm water at 100 ºF for hand washing
  • liquid soap
  • nail brush (follow state and local public health department recommendations)
  • disposable paper towels and/or air blowers
  • toilet paper
  • covered trash container that opens with a foot pedal


Clean restrooms daily and keep the doors closed. Remove trash daily.


Maintain Good Ventilation


Good ventilation is critical. Ventilation removes steam, smoke, grease, and heat from food preparation areas and equipment and helps maintain indoor air quality.


Good ventilation eliminates condensation and other airborne contaminants. It also reduces


  • the accumulation of dirt in the food preparation area
  • odors, gases, and fumes
  • mold growth by reducing humidity


To promote good ventilation, be sure to


  • use exhaust fans to remove odors and smoke
  • use hoods over cooking areas and dishwashing equipment
  • check exhaust fans and hoods regularly to make sure they are clean and operating properly
  • clean hood filters routinely according to the instructions provided by the hood manufacturer


Maintain Clean and Neat Trash Collection Areas


  • Garbage must be kept away from food preparation areas. It should not be allowed to accumulate anywhere except in designated garbage storage areas.
  • Garbage containers must be leak-proof, waterproof, pest-proof, durable, and easy to clean and sanitize.
  • Garbage containers should be cleaned and sanitized frequently and thoroughly, inside and out.
  • Trash receptacles should be emptied often so garbage does not overflow from containers.


Insect & Rodent Control


Maintain an Effective Pest Control Program


Cleanliness and good maintenance are keys to preventing pest infestation. The foodservice environment is prone to attract bugs and many other pests. Pests may be brought in when food and other supplies are delivered. Pests may also enter the building through gaps in floors or walls. Prevention is critical in pest control. Have an ongoing pest prevention program and regular pest control by a licensed pest control operator.


How to Prevent Pest Infiltration


  • Fill openings or cracks in walls and floors with putty, plastic wood, or a similar product.
  • Fill openings around pipes or equipment fittings.
  • Screen all windows, doors, and outer openings. Keep them in good repair.
  • Use self-closing doors that open outward.
  • Inspect food supplies before storing or using them.
  • Keep food in labeled containers approved for food storage. These containers should have tight-fitting lids.
  • Do not store food or containers directly on the floor.
  • Remove and destroy any food that shows evidence of infestation.
  • Maintain proper temperatures in storage areas.
  • Clean grease traps regularly to prevent a grease build-up that could cause a drain blockage. Drain blockage could lead to overflow which causes an unpleasant odor, contamination, and attracts pests.
  • Install an air door at foodservice entrances to prevent bugs from flying in.



In the event of infestation, the foodservice manager should alert a licensed pest control operator so immediate steps can be taken to eliminate the pests.


The three most common pests are cockroaches, flies, and rodents.


Cockroaches live and breed in holes, damp places, behind boxes, in seams of bags, and in folds of paper. They like any place that is dark, warm, moist, and hard to clean. Cockroaches’ hairy legs are full of debris and disease-causing organisms such as bacteria, fungi, parasite eggs, and viruses. One female cockroach produces millions of offspring in her lifetime. Since cockroaches generally search for food at night, seeing one in the daytime is a sign of a major infestation.


Other signs of infestation include: 

  • a strong, oily odor
  • feces that look like large grains of pepper
  • brown, dark brown, dark red, or black capsule-shaped egg cases


Flies feed on human and animal wastes and garbage and can transport a wide range of foodborne illnesses. They can enter a building through holes the size of a pinhead and can contaminate food with their mouth, footpads, hair, or feces. One female can produce thousands of offspring in one breeding season.


Flies are attracted to places protected from the wind and to edges such as garbage can rims. They lay their eggs in warm decaying material protected from sunlight and are fond of human waste areas. In warm summer weather, flies can mature from larvae to adults in only 6 days.


Rodents carry many disease-causing organisms and parasites. In fact, one fecal dropping from a rat can contain several million bacteria. When rodents leave feces, urine, and other filth on food products and around the facility, these organisms can be easily transmitted to people.


Rodents are prolific breeders, producing as many as 50 offspring in a span of 1 year. They tend to hide during the day, but can be spotted by telltale signs. These signs include the following: 

  • droppings
  • gnawing
  • tracks on dusty surfaces
  • nesting materials
  • holes in baseboards, wall board, and in other wood


Smallware & Equipment Sanitization


Smallware is a collective term used to include dishes, flatware, preparation and serving utensils, measuring devices, cooking pots and pans, and other small equipment that can be moved to the three-compartment sink or dishwasher for cleaning and sanitizing. Follow state and local public health department regulations on how to clean and sanitize smallware. The information below is for general guidance.


All surfaces that come in contact with food must be cleaned and sanitized. To clean a surface means to remove visible food particles—what can be seen on the surface. To sanitize a surface means to use either a chemical or heat to reduce the number of microorganisms or other contaminants to a level that is not harmful. The first step is cleaning; the second step is sanitizing.


Use a Sanitizer Test Kit


A test kit designed for a specific sanitizer should be used to check the concentration of the sanitizing solution. A foodservice supplier who sells sanitizers may also have the test kits for each type of sanitizer. Mix, use, and test the sanitizing solution as recommended by the state and local public health department. Refer to the manufacturer’s directions for specific mixing, storing, and first-aid instructions. When a sanitizing solution is exposed to air, detergent, and food particles, the solution becomes less effective. Sanitizing solutions should be tested frequently.


Select from Two Methods of Sanitizing — Chemical or Heat


Chemical Sanitizing


Chemical sanitizing can be accomplished by immersing an object in, or wiping it down with, a sanitizing solution and allowing the solution to remain in contact with the surface for a specified amount of time. Use only EPA-approved (Environmental Protection Agency) chemical sanitizers for food-contact surfaces. Household bleach can be used as a sanitizer only if the label indicates it is EPA registered.


Mix, test, and use the sanitizing solution as recommended by the state and local public health department. Refer to the manufacturer’s directions for specific mixing, storing, and first-aid instructions.


The three most common chemical sanitizers are: 

  • Chlorine – This sanitizer is the most commonly used and is the least expensive. It is effective in hard water, but is inactivated by hot water above 120 ºF. Chlorine bleach solutions must be tested regularly and changed as necessary to ensure that the solution is working to sanitize. Using too much chlorine in a solution can pit stainless steel and aluminum surfaces, while using too little will not sanitize the surface.
  • Iodine – Iodine is more expensive and less effective than chlorine. However, an iodine sanitizing solution is not as quickly deactivated by food particles as a chlorine solution.
  • Quaternary Ammonium Compounds (Quats) – This sanitizer is not as quickly deactivated by food particles as a chlorine solution, is noncorrosive to metal surfaces, and nonirritating to skin. However, it leaves a film on surfaces and does not kill certain types of microorganisms.



Chlorine Sanitizing Solution for Equipment, Food-Contact Surfaces, and Utensils


Rule-of-thumb mixtures for chlorine sanitizing solutions


50 PPM solution for immersion

1 tablespoon (1/2 fluid ounce) 5% chlorine commercial bleach mixed with 4 gallons of water. The solution should be in contact with the surface to be sanitized for 7 seconds at temperatures between 75 ºF and 115 ºF. Be aware that very hot water may prevent chlorine bleach from sanitizing.


This sanitizing solution can be used to sanitize a food thermometer after every use.

100 PPM solution for immersion

1 tablespoon (1/2 fluid ounce) 5% chlorine commercial bleach mixed with 2 gallons of water
200 PPM solution for immersion1 tablespoon(1/2 fluid ounce) 5% chlorine commercial bleach mixed with 1 gallon of water


Use the manufacturer’s label directions for specific information on mixing, storing, and first aid. Test with a test kit.


Heat Sanitizing


Heat sanitizing involves exposing equipment to high heat for an adequate length of time. This may be done manually by immersing equipment into water maintained at a temperature of 171 ºF to 195 ºF for at least 30 seconds. In a dishwashing machine, a good rule of thumb is to wash at 150 ºF and rinse at 180 ºF. But remember, temperature may vary depending on the type of machine used and requirements of the state and local public health department.


Thermometers and heat-sensitive tapes and labels are available for determining whether adequate sanitation temperatures have been achieved.


Sanitizing Smallware


To clean and sanitize smallware, the kitchen must have a sink with at least three separate compartments for manually cleaning, rinsing, and sanitizing, or a mechanical dishwasher that functions properly. There should be a separate area for scraping and rinsing food and debris into a garbage container or disposal before washing and a separate drain board for clean and soiled items.


Manually Sanitize Smallware in a Three-Compartment Sink


Step 1 - Clean and sanitize sinks that will be used for washing and sanitizing smallware.


Step 2 - Scrape and rinse food into garbage container or disposal. Pre-soak items, such as flatware, as necessary.


Step 3 - In the first sink, immerse and wash the smallware in a clean detergent solution at 110 ºF or the temperature specified on the cleaning agent manufacturer’s label directions. Use a brush or a cloth to loosen and remove any remaining visible food particles.


Step 4 - In the second sink, rinse the smallware using clear, clean hot water (110 ºF) to remove all traces of food, debris, and detergent.


Step 5 - In the third sink, sanitize.


CHEMICAL: Immerse the clean items in a chemical sanitizing solution at the appropriate temperature for the correct amount of time. Be sure all surfaces of the clean items are covered with hot water or the sanitizing solution. Follow manufacturer’s label directions for mixing the sanitizing solution and using the required contact time for sanitizing. Check the concentration of the chemical sanitizer at regular intervals using a test kit. Be aware that hot water deactivates some chemical sanitizers, so read and correctly follow the manufacturer’s directions for using the chemical. Always read the Material Safety Data Sheet before using a chemical.




HEAT: Immerse or spray rinse clean items in hot water at 171 ºF to 195 ºF for at least 30 seconds. Some state public health department codes require a temperature of 180 ºF. If soapsuds disappear in the first compartment or remain in the second, the water temperature cools, or water in any compartment becomes dirty with food particles or cloudy from grease, empty the compartment and refill it.


Step 6 - Air dry all items on a drain board. Wiping can re-contaminate equipment and can remove the sanitizing solution from the surfaces before it has finished working.


Step 7 - Store. Make certain all smallware is dry in order to avoid retaining moisture that fosters bacterial growth.



Sanitize Smallware in a Mechanical Dishwasher


When sanitizing smallware (dishes, trays, flatware, glasses) in a dishwasher, follow the manufacturer’s directions. Check the temperature of the water in the wash and rinse cycles. The temperature may vary depending on the type of dishwashing machine used and requirements of the state and local public health department.


Check Dishwasher Temperatures


Although dishwashers have temperature gauges for each compartment, it is useful to confirm that the gauge is accurate using another type of thermometer. There are two types of thermometers that can be used to confirm the accuracy of dishwasher thermometer gauges:


  • Waterproof maximum/minimum-registering thermometer 
  • Self-adhering temperature-sensitive label


waterproof maximum/minimum-registering thermometer is a type of thermometer that is placed in a dish rack to go through the dishwasher cycle with soiled trays and flatware. It is set to register the highest temperature of the cycle to confirm that the required temperature is reached in a sanitizing rinse cycle.


Another tool for checking the temperature is a self-adhering temperature-sensitive label. This type of sensor attaches to the surface of a clean dish/tray and changes color to record the dishware surface temperature during dishwashing. Labels are available for various temperatures. For example, to determine whether the temperature in the final sanitizing rinse of a dishwasher reaches 180 ºF, a single temperature 180 ºF label could be attached to a clean tray to go through the cycle. When the temperature has been reached, the label changes color. The label can be removed from the tray at the end of the dishwasher cycle and placed in a log to document temperature.


Before using or purchasing either of these types of thermometers to confirm the temperature in a dishwasher, check with the state and local public health department on what is recommended. Be knowledgeable about the correct use of each thermometer to decide which one best meets the needs of the foodservice operation.


How should large equipment be cleaned and sanitized?


To keep large or in-place equipment free of harmful levels of bacteria or other contaminants, it is necessary to clean and sanitize all surfaces that will come into contact with food. This is especially important after any possible contamination such as slicing a deli meat on a slicer or mixing a meat salad in a mixer.


Wash, rinse, and sanitize tables, stoves, sinks, slicers, choppers, mixers, and large cooking utensils after each use. This rule also applies to equipment used to clean other food contact surfaces.


Scrub surfaces, such as cutting boards, with a detergent solution and a stiff-bristled nylon brush. Then rinse in clear, clean water and sanitizing solution after every use. For the use and care of wooden cutting boards, surfaces, or utensils, follow state and local public health department recommendations. Synthetic cutting boards can be sanitized in a three-compartment sink or in a dishwasher, depending on their size. Follow state and local public health department recommendations.


Use the Chemical Method to Sanitize Equipment

Immerse or wipe down with commercial sanitizer. Follow manufacturer’s label directions for mixing and using the sanitizer. Use a test kit to test for correct concentration. Always read the Material Safety Data Sheet before using a chemical.


Sanitize In-Place Equipment

Read and follow the manufacturer’s directions for cleaning and sanitizing the piece of equipment. Follow the general steps described below.


Step 1 - Unplug electrically powered equipment, such as meat slicers and mixers.


Step 2 - Remove loose food particles and scraps.


Step 3 - Wash, rinse, and sanitize any removable parts using the manual immersion method in a three-compartment sink.


Step 4 - Wash the remaining food-contact surfaces and rinse with clean water. Wipe down with a chemical sanitizing solution mixed according to the manufacturer’s directions.


Step 5 - Clean surfaces that do not come in contact with food using a clean wiping cloth. Allow all parts to air dry before reassembling. Clean the wiping cloth before and during use by rinsing it in a sanitizing solution.


Step 6 - Re-sanitize the external food-contact surfaces of the parts that were handled when the equipment was reassembled.



All equipment should be kept clean and sanitized. Although some equipment is not used for food preparation, all equipment that has any contact with food should be cleaned and sanitized on a routine basis. Follow manufacturer’s directions to clean and sanitize cabinets, shelf racks, dish dollies, dish and tray dispensers, pan racks, bakery racks, food holding equipment, equipment used to transport foods, and ice machines. Remember to keep all food preparation equipment and utensils free from dirt, dust, and other forms of contamination.