To prevent backflow at the hose attachment of an equipment sink, which of the following must be installed?

The installation of a hose-bib vacuum breaker is essential to prevent backflow at the hose attachment of an equipment sink. This device acts as a protective barrier, ensuring that any contaminated water does not flow back into the potable water supply when there is a drop in water pressure or a back-siphonage situation. The vacuum breaker allows air to enter the system, preventing the creation of a vacuum that could pull dirty water back into drinkable water lines.

In a food service environment, maintaining the integrity of the drinking water supply is crucial for health and safety. The hose-bib vacuum breaker is specifically designed to work with hose connections and is an effective method for safeguarding against hazardous backflow scenarios that could result from utilizing hoses for cleaning or other purposes.