What is "trap seepage," and how can it be prevented?

Trap seepage refers to a situation where water in a plumbing trap evaporates, which allows sewer gases to escape into the living space. Traps are designed to hold a certain amount of water, creating a seal that prevents these noxious gases from entering the home. The correct preventative measure involves ensuring that the trap is always filled with water, which maintains the necessary barrier against sewer gas infiltration.

If the water in the trap evaporates due to evaporation caused by prolonged periods of non-use or inadequate design, the seal is lost, leading to potential health hazards from sewer gas exposure. Therefore, maintaining proper water levels in traps, especially in seldom-used fixtures, is crucial for preventing trap seepage and maintaining a safe indoor environment.