What does an air gap help prevent?

An air gap is a critical safety feature in plumbing and food safety that prevents the backflow of contaminated water. This occurs when there's a drop in water pressure, which can cause water from a contaminated source to siphon back into the potable water supply. The air gap creates a physical barrier that separates the water supply from any potential contaminants, ensuring that clean drinking water remains safe and uncontaminated. This is particularly important in settings such as kitchens and food preparation areas where cross-contamination could easily occur if backflow were allowed.

While the other options—spread of foodborne illness, food spoilage, and cross-contamination—are significant concerns in food safety and culinary practice, they are not directly prevented by the air gap. Instead, these issues are typically addressed through proper food handling practices, sanitation methods, and cooking techniques.