Cross-contamination is the unintended transfer of harmful microorganisms, allergens or foreign substances from one surface, product, person or environment to another, and is a primary cause of food-safety incidents in processing and logistics.
In trade practice
Processing facilities manage cross-contamination through physical zoning that separates raw from ready-to-eat areas, colour-coded equipment, controlled personnel flows and validated cleaning procedures. In logistics, shared trailers carrying frozen and ambient products or allergen-containing and allergen-free goods require documented risk assessments. Allergen cross-contamination is a particular concern in facilities handling nuts, sesame and gluten-containing grains. GFSI scheme audits assess zoning plans, cleaning records and swab results as evidence of control.
In a specification
A supplier specification or facility approval form may require a site zoning plan, a cleaning validation summary and confirmation of which allergens are handled on shared lines or in shared storage areas.