Concept · under Contamination and allergens
Cross-contamination on the line: three routes, two fixes
Cross-contamination is germs moving into food from somewhere else: from raw food to ready-to-eat food, from hands, or from a tool or surface. You stop it with one of two moves. Keep raw and ready-to-eat food apart, or clean and sanitize anything that touched raw before it touches anything else.
- ExamPFH
- Questions here7
- UpdatedOct 14, 2026
On this page 6 sections
What it looks like on a line
On a busy line it rarely looks like much. A thermometer probe goes from a raw burger patty straight into the tuna salad. The towel from the raw-chicken station wipes down the pass. A cracked flat of shell eggs drips onto the cut melon on the shelf below. Each one carries germs to food that won't see heat again.
Germs are one of three hazard types. A sanitizer splash in the soup is chemical, a shard from a chipped glass is physical; both are covered under contamination and allergens.
The three routes
Station by station
Walk-in and reach-ins
Raw animal food goes below ready-to-eat (RTE) food, and raw beef, fish, pork and poultry are kept apart from each other (3-302.11). The full shelf order is on storage, labeling and rotation.
Prep
Raw and RTE food get their own equipment, or their own time slot with the turnaround from the top of this page in between (4-602.11(A)).
Thermometers
A probe is a tool like any other. It gets cleaned and sanitized before it goes into the next food.
Wiping cloths
Wet cloths wait in sanitizer between uses, and cloths used on raw animal food surfaces stay separate from the rest (3-304.14).
Hands
Wash when you go from raw food to RTE food, even if the next task takes ten seconds (2-301.14(G)).
Cross-contamination or cross-contact?
| Point | Cross-contamination | Allergen cross-contact |
|---|---|---|
| What moves | Germs: bacteria, viruses, parasites | Allergen protein from one of the Big 9 |
| Does cooking fix it | Cooking to the required temperature kills most germs in raw food | No. The protein survives heat |
| Who gets hurt | Anyone who eats the food | A guest with that allergy, sometimes from a trace |
| Where the term comes from | FDA Food Code, 3-302.11 | Industry term; the Food Code covers it under allergy awareness training (2-103.11(O)) |
Raw to ready-to-eat: try it
Raw meat, shared tools and what has to happen between jobs.
Each question is a chit, an order ticket. Answer it and it flips to show why every option is right or wrong.
No. 01
What is the best practice to prevent cross-contamination when preparing raw chicken and fresh vegetables?
Pick one. The chit flips to a note on every option.
Notes on No. 01
- A
Use separate cutting boards and utensils for each Correct: Separate boards and knives keep raw chicken juices away from vegetables that may be served without cooking.
- B
Prepare vegetables first, then chicken using the same board Prepping vegetables first is only a fallback, and the board still has to be washed, rinsed, and sanitized after the chicken.
- C
Wash the cutting board with water between uses Water alone doesn't remove raw chicken juices or kill bacteria; boards need washing, rinsing, and sanitizing.
- D
Wipe the cutting board with a cloth between uses Wiping with a cloth spreads raw chicken juices around and onto the cloth.
- A
No. 02
Which of the following is a key step in preventing cross-contamination?
Pick one. The chit flips to a note on every option.
Notes on No. 02
- A
Using designated color-coded cutting boards Correct: Assigning board colors to raw meat, poultry, seafood, and produce makes it easy to keep raw juices off ready-to-eat food.
- B
Preparing raw and ready-to-eat foods at once Prepping raw and ready-to-eat food side by side lets splashes and juices reach the food that won't be cooked.
- C
Using the same utensils to save on washing Shared utensils carry raw meat bacteria straight to the next food they touch.
- D
Washing all foods together in one sink Washing everything together mixes raw-product contamination into produce and other foods.
- A
No. 03
How should raw poultry be handled during preparation?
Pick one. The chit flips to a note on every option.
Notes on No. 03
- A
Use designated tools and clean all surfaces after Correct: Dedicated boards and utensils for poultry, then washing, rinsing, and sanitizing every surface it touched, keeps Salmonella off other food.
- B
Rinse the poultry and the board with water only Rinsing raw poultry splashes bacteria around the sink, and water alone doesn't sanitize the board.
- C
Use any available cutting board that's free Grabbing any free board risks using one meant for ready-to-eat food.
- D
Wipe surfaces clean with a cloth when done A wipe smears poultry juices around, while surfaces need cleaning and sanitizing.
- A
No. 04
What is the primary concern with double-dipping utensils?
Pick one. The chit flips to a note on every option.
Notes on No. 04
- A
It slows down the line during service Speed isn't the issue; the problem is what the utensil carries back into the food.
- B
Transfer of bacteria and allergens Correct: Putting a used utensil back into food moves saliva, bacteria, and allergens from one food or mouth into the whole batch.
- C
Damage to utensils from repeated use Utensil wear isn't the concern here, contamination is.
- D
Extra food waste from tasting portions Waste may be a cost issue, but the safety problem is contamination carried back into the food.
- A
No. 05
When using a slicer for different types of meat, what should be done between uses?
Pick one. The chit flips to a note on every option.
Notes on No. 05
- A
Rinse the blade with hot water Hot water alone doesn't remove meat residue or kill bacteria on the blade.
- B
Clean and sanitize the slicer Correct: Washing, rinsing, and sanitizing between meats, especially raw and cooked or allergen items, keeps residue from moving from one to the next.
- C
Continue using it as is Running a new meat over old residue carries bacteria and allergens straight into it.
- D
Wipe it with a clean cloth A wipe smears residue around the guard and carriage and doesn't sanitize.
- A
No. 06
What should be done between cleaning raw meat preparation areas and ready-to-eat food areas?
Pick one. The chit flips to a note on every option.
Notes on No. 06
- A
Use same tools immediately Moving tools straight from raw meat areas to ready-to-eat areas carries bacteria with them.
- B
Change water only Fresh water in the bucket doesn't help if the brushes and cloths are still contaminated.
- C
Clean and sanitize cleaning tools Correct: Tools used on raw meat areas must be cleaned and sanitized, or swapped, before they touch surfaces for ready-to-eat food.
- D
Just rinse tools A rinse leaves bacteria on brushes and cloths.
- A
No. 07
What should be done with cutting boards after using them with raw meat?
Pick one. The chit flips to a note on every option.
Notes on No. 07
- A
Wash, rinse, and sanitize immediately Correct: Washing removes residue, rinsing removes detergent, and sanitizing kills what's left, so the board is safe for the next food.
- B
Wipe with a cloth and set aside Wiping doesn't remove raw meat juices from knife cuts in the board or kill bacteria.
- C
Run under hot water only Tap-hot water isn't hot enough to sanitize and doesn't remove fat and residue.
- D
Just rinse with water and reuse Rinsing leaves bacteria behind, and reusing the board spreads them to the next food.
- A
Nothing matches both filters. Clear one of them.
Sources
- FDA Food Code 2022 — 3-302.11 separation; 4-602.11 when equipment is cleaned; 3-304.14 wiping cloths; 2-301.14 when to wash; 2-103.11(O) allergy awareness checked Oct 13, 2026