This is one of the most common causes of food poisoning, and is caused by harmful germs spreading onto food from people’s hands, raw food, kitchen utensils, surfaces and equipment. Cross contamination happens when pathogenic bacteria is unintentionally transferred to foods that did not originally contain them, thereby making the food unsafe to eat.

How to prevent the cross contamination of food

Below are some tips on how to stop the transfer of disease-causing organisms from contaminating food or previously clean areas.

  • If possible have completely separate equipment, food preparation areas and storage areas for raw and cooked meat and cooked foods.
  • Keep the physical handling of ready to eat food to a minimum, do this by using tongs and spoons to handle food.
  • Have as few people as possible handle food.
  • Ensure that all food handlers maintain high levels of personal hygiene at all times.
  • Follow appropriate sanitation measures.
  • Keep ready to eat food covered until it is about to be served.

Common causes

  • Using the same equipment, to handle raw and cooked food.
  • Raw food touching other food, ready to eat meals or surfaces.
  • The juices from raw food dripping onto other food.
  • Food handlers with dirty hands touching food.

Do not

  • Allow poultry, raw meat or unwashed raw vegetables to touch other foods.
  • Let the juices of raw food come in contact with cooked food.
  • Mix freshly prepared food with foods being held for service.
  • Feed contaminated food to pets or livestock.

Direct cross contamination
This happens when straight forward contact is made between raw meat and cooked meat.

Indirect cross contamination
This happens when bacteria is spread via food handlers, equipment, utensils or work surfaces. It can also happen through fridge door handles, knives, chopping boards, work surfaces and even clothes.

Regularly remove and clean visible dirt, rubbish and food particles from food preparation areas.

Cleaning equipment and surfaces
Always clean kitchen accessories and worktops before you start working on food, and also after you have finished.

Cutting boards

  • Use separate colour coded cutting boards for different meats or vegetables. Each colour is designed for use with a specific food type.
  • Do not cross use a cutting board to cut meat, and then straight after use it to slice vegetable. You must wash the cutting board first, or better still use a separate one.

Use chemical disinfectants to regularly deep clean food preparation areas.

Equipment and utensils

  • The dual usage of any kitchen utensils and equipment for raw food is dangerous.
  • Food equipment and utensils should be made of smooth, non-absorbent materials that are free from spaces where bits of food could become trapped.
  • Damaged equipment should be thrown away. Loose parts can lead to gaps which in turn can harbour bacteria.

Handling food
Rather than picking up food with your bare hands, consider wearing gloves or use dedicated tongs, serving spoons and other utensils.

Food handlers who are ill should not work with any food. They should only return to work after being clear of any symptoms for at least 48 hours.

Remove any jewellery and rings before you start working with any food. Bacteria can hide underneath them, or they could fall of into food.

Use different knives for cutting raw and ready to east food. To make it simpler for staff consider using different coloured knives.


  • Always use a clean container to hold any leftovers.
  • Wrap leftovers in leak-proof plastic bags.
  • Keep different types of leftovers separate.

Keep pets like cats or dogs away from any food preparation area.


  • Do everything possible to remove and discourage pests, insects, birds or rodents from any food preparation area.
  • Carry out regular checks and look for signs of infestation.

Do not put cooked food on any plate that had previously held raw foods. Only re-use a plate after it has been thoroughly washed and dried.

Protective clothing
Wear gloves, hairnets, aprons and face masks when carrying out any food handling activities.


  • Store raw meat at the bottom of any shared refrigerator.
  • Any raw meat in a fridge must be adequately wrapped to prevent leakage of juices.
  • Place different foods in separate spots in the refrigerator in order to prevent one product from contaminating another.
  • Fruits and vegetables should be placed on the top shelf of the refrigerator.

When carrying food around keep all raw, cooked and ready to eat food in separate bags. Also ensure that they are wrapped up properly so that they do not touch each other whilst they are being moved around.

Use separate thermometers for raw and cooked meats.
Clean probe thermometers after they have been used.

Thawing food in a fridge
The food should be placed in a drip-proof container and kept at the bottom of the refrigerator, underneath any other foodstuff.

Washing your hands
Wash your hands properly after going to the toilet, sneezing, touching your nose, handling raw food, handling waste or cleaning dishes etc. Wash them with clean, hot water and soap, and dry them thoroughly (preferably with a paper towel) before touching any food.

Work surfaces
Use a separate parts of a worktops to prepare raw and ready to eat food.

Washing utensils

  • Use hot water and soap to thoroughly wash all knives, spoons and pots and pans etc.
  • Do not wash raw food equipment in a sink at the same time as cleaning ready-to-eat equipment.
  • Allow utensils to air dry, avoid using cloths to dry them.

The importance of preventing cross contamination

  • Helps to keep people free from food poisoning.
  • Helps you to comply with food safety laws and relevant legislation.


Related links
Food hygiene course online