ServSafe Forms of Contamination (Biological, Chemical & Physical)

Question 1

Which of the following is an example of biological contamination in a food service operation?

Accepted Answer

Bacteria transfer from raw chicken to a ready-to-eat salad

Answer

Biological contamination involves living organisms — primarily bacteria, viruses, parasites, and fungi — getting into food. Transferring bacteria from raw chicken (a biological hazard) to a ready-to-eat food is a classic example. Metal shavings are physical contamination; cleaning solution is chemical contamination.

Question 2

Which of the following is classified as one of the Big 6 pathogens that food workers diagnosed with it MUST be reported to the person in charge?

Accepted Answer

Norovirus

Answer

The ServSafe Big 6 pathogens — Norovirus, Hepatitis A, Salmonella Typhi, Shigella spp., Shiga toxin-producing E. coli (e.g., O157:H7), and Nontyphoidal Salmonella — require immediate reporting to the PIC and possible exclusion from the operation. Staph aureus and B. cereus are common illness causes but are not on the Big 6 list.

Question 3

A food handler notices a small shard of glass in a dessert before it is served. What type of contamination is this?

Accepted Answer

Physical contamination

Answer

Physical contamination occurs when foreign objects — such as glass, bone fragments, metal, or packaging material — accidentally get into food. Biological contamination involves microorganisms; chemical contamination involves substances like cleaning agents or pesticides.

Question 4

Which of the following scenarios describes chemical contamination of food?

Accepted Answer

Sanitizer is improperly rinsed from a food-contact surface before use

Answer

Chemical contamination occurs when substances such as cleaners, sanitizers, pesticides, or toxic metals contact food. Residual sanitizer left on a food-contact surface is a direct chemical contamination risk. The other options represent biological (raw beef), biological (insect), and physical (hair) contamination respectively.

Question 5

Foodborne illness caused by toxins produced by Staphylococcus aureus is best characterized as which type of contamination risk?

Accepted Answer

Biological, because the source is a living organism that produces the toxin

Answer

Even though the illness is caused by the toxin (a chemical substance), the contamination is classified as biological because the hazard originates from a living microorganism (Staphylococcus aureus). ServSafe classifies all microorganism-sourced hazards — including their toxins — under biological contamination.

ServSafe Food Safety Test Prep Practice Test

ServSafe Food Safety Test Prep Practice Test

ServSafe Forms of Contamination (Biological, Chemical & Physical)