According to the USC, what is the correct height for installing a reduced pressure zone?

The correct height for installing a reduced pressure zone device, as specified by the Uniform Plumbing Code (UPC), is indeed outlined in the choice stating 12 inches above grade but no more than 36 inches. This requirement is critical for ensuring that the device functions correctly while also providing adequate clearance for maintenance and preventing potential flooding issues.

Having the device set at a height of at least 12 inches above grade ensures that it remains above ground water levels, which is paramount for preventing contamination of the potable water supply in case of flooding. Limiting the height to no more than 36 inches strikes a balance between accessibility and functionality, allowing plumbers to easily service and inspect the device without unnecessary complications.

Options that suggest specific heights outside the stated range, whether too low or too high, do not adhere to the UPC guidelines, which is why they would not be considered correct. By establishing this height requirement, the UPC aims to promote safety and reliability in plumbing systems, particularly in protecting against backflow that could introduce contaminants into the drinking water supply.