What prevents tray siphonage in a plumbing system?

Tray siphonage occurs when a liquid in a trap is siphoned away, often as a result of negative pressure in a plumbing system. This can lead to unpleasant odors emanating from the plumbing system and can cause other issues, such as allowing sewage gases into the building.

Vacuum breakers are devices designed to prevent this siphoning effect by breaking a vacuum that may form in the system. When a negative pressure develops, a vacuum breaker allows air to enter the system, effectively neutralizing the vacuum and preventing the siphon effect. This ensures that the water seal in traps remains intact and functional, thereby maintaining proper drainage and preventing backflow of unwanted gases.

In contrast, drainage systems, vent systems, and vertical pipes have specific functions in plumbing systems. While they play roles in overall drainage and venting, it is specifically the vacuum breaker that directly addresses the issue of tray siphonage by providing a safeguard against loss of traps' liquid seals.