Manufacturers cannot just segregate common products other product types as a means of dealing with the risk to patient and animal safety. Although this may prevent contamination of other product classes it does not address the possibility for cross contamination within product classes. The approach taken to control cross contamination between individual products within a class produced in the same dedicated area should follow the principles in Q&A 3. This should include implementation of appropriate organisational and technical control measures to prevent contamination between such products within product specific HBELs.