Final answer:
A cross-connection is a link between a potable water supply and unsafe water, posing serious health risks. It is essential to prevent such connections to maintain the safety and cleanliness of drinking water systems.
Step-by-step explanation:
A cross-connection is the link between a potable water supply and unsafe water. This can be a serious health hazard as it may allow contamination of drinking water by various microorganisms or chemicals, leading to diseases and illnesses. Cross-connections must be properly managed or eliminated to ensure the safety of drinking water systems.
Instances of cross-contamination can occur when the clean water supply is connected with a non-potable source, which could happen in various household appliances if they are not properly designed or installed. For example, backflow from a sink into a dishwasher could contaminate the clean water supply if proper backflow prevention devices are not installed. Therefore, special attention is given to plumbing systems to prevent such connections and ensure water safety.