When installing a hose bib on the exterior of a building, what backflow prevention measure is typically required by plumbing codes to prevent contamination of the potable water supply?

Question: When installing a hose bib on the exterior of a building, what backflow prevention measure is typically required by plumbing codes to prevent contamination of the potable water supply?

Answer options:

• A Pressure Vacuum Breaker (PVB) upstream of the hose bib.
• A Double Check Valve Assembly (DCVA) at the building's main water entry.
• An Atmospheric Vacuum Breaker (AVB) at the hose bib. ✅ An integral vacuum breaker designed into the hose bib assembly itself.

Correct answer: An integral vacuum breaker designed into the hose bib assembly itself.

Explanation: For hose bibs, especially frost-free types, an integral vacuum breaker is a common and code-approved method to protect against back-siphonage when a hose is left connected and submerged in contaminated water. While AVBs can be used, integral devices are often part of quality hose bibs, providing direct protection at the point of use. PVBs and DCVAs are typically for higher hazard or larger-scale applications.