Which of the following is NOT a type of chemical sanitizer?

The correct answer is calcium, as it is not classified as a chemical sanitizer used for food safety. Chemical sanitizers are formulated substances that reduce the number of microorganisms to safe levels on surfaces that come into contact with food. Common examples of chemical sanitizers include chlorine, quaternary ammonium compounds, and iodine.

Chlorine is widely used in various sanitation processes because of its effectiveness against a broad spectrum of pathogens. Quaternary ammonium compounds, often referred to as "quats," are also popular sanitizers due to their stability and safety in handling. Iodine is another effective sanitizer, frequently used in food processing to eliminate harmful bacteria.

Calcium, on the other hand, while it may play a role in various chemical processes involving food safety, is not recognized as a sanitizer. It typically does not exhibit the necessary antimicrobial properties required to qualify as a food-safe sanitizer and doesn’t meet the criteria set for reducing or eliminating microbes on food preparation surfaces. This understanding is essential for ensuring food safety practices in any food service or handling environment.