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Practice and exam technique

Practice questions: contamination and cross-contamination

Compiled by the Sitonce editorial team from the FDA Food Code and the accredited providers listed belowUpdated 3 min readFacts verified 1 September 2026
The short answer

Contamination is fifteen of the eighty questions, the largest single area. These five cover storage order, bare-hand contact, cross-contact and the glove scenarios that generate the most wrong answers.

Fifteen questions. Nothing else on the paper is worth as much, and none of it is conceptually difficult once the reasoning is in place.

Question 1

A walk-in has four shelves. Which arrangement is correct, top to bottom?

  1. Poultry, ground beef, salmon, prepared salads
  2. Prepared salads, salmon, ground beef, poultry
  3. Prepared salads, ground beef, salmon, poultry
  4. Salmon, prepared salads, poultry, ground beef
Answer: B. The order follows required cooking temperature, lowest at the top. Salads are ready-to-eat and go highest, then salmon at 145°F, ground beef at 155°F, poultry at 165°F. Anything that drips lands on food that will be cooked hotter than the food it came from.
Question 2

A cook wearing gloves handles raw chicken, then takes payment at the till, then plates a sandwich without changing gloves. Which statement is correct?

  1. Acceptable - no bare-hand contact occurred
  2. Acceptable if the gloves are intact
  3. Not acceptable - gloves must change when the task changes
  4. Not acceptable - gloves may not be worn at a till
Answer: C. Gloves must be changed when the task changes, when they tear, and after handling raw animal food, with handwashing at each change. The scenario avoids bare-hand contact throughout and is exactly what the rule exists to prevent, which is why option A is there.
Question 3

A customer with a shellfish allergy orders chips. The chips are cooked in oil that has been used for breaded shrimp. What is the correct description?

  1. Cross-contamination, controlled by cooking temperature
  2. Cross-contact, not controlled by cooking
  3. Acceptable, because the oil reaches a high temperature
  4. Acceptable, because the chips contain no shellfish
Answer: B. Allergen protein transfers into the oil and is not destroyed by heat. This is cross-contact rather than cross-contamination, no pathogen is involved, and a trace is enough to cause a reaction. Cooking answers nothing here.
Question 4

Which is a food-contact surface?

  1. The outside of a delivery box
  2. The interior of an ice machine
  3. The floor beneath a prep table
  4. The handle of a walk-in door
Answer: B. Ice is a food, so the interior of the machine is a food-contact surface and mold in the bin is a contamination finding. The other three are surfaces that require cleaning but are not in contact with food.
Question 5

A server drops a serving spoon on the floor during service. What should happen?

  1. Rinse it under hot running water and continue
  2. Wipe it with a sanitizer cloth and continue
  3. Take it out of service for full cleaning and sanitizing
  4. Continue using it if the floor was recently mopped
Answer: C. A dropped utensil goes for full warewashing - wash, rinse, sanitize, air dry. Rinsing does not sanitize, and a sanitizer cloth on a soiled surface achieves very little because organic matter binds the active chemical.

The connection worth noticing

Questions one and three both come down to cooking temperature - one because it sets the storage order, the other because it does not help at all.

Knowing which situations cooking fixes, and which it does not, resolves a surprising share of this area.

Common questions

What is the correct cooler storage order?

Ready-to-eat on top, then seafood, whole cuts of beef and pork, ground meat, and poultry on the bottom. The order follows required cooking temperature, lowest at the top.

Do gloves prevent cross-contamination?

Only if changed correctly. A worker who handles raw chicken, then money, then a sandwich in the same gloves has transferred contamination twice without ever touching food bare-handed.

Is a shared fryer cross-contact?

Yes. Allergen protein transfers into the oil and heat does not destroy it, so no pathogen is involved and cooking does not help.

Is the inside of an ice machine a food-contact surface?

Yes, because ice is a food. Mold or slime in an ice bin is a contamination finding rather than a cleanliness issue.

What happens to a dropped utensil?

It goes for full cleaning and sanitizing - wash, rinse, sanitize, air dry. Rinsing does not sanitize, and a sanitizer cloth on a soiled surface achieves very little.

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