What is the primary purpose of a plumbing trap?

The primary purpose of a plumbing trap is to block odors. Plumbing traps are designed to hold a small amount of water, which creates a seal that prevents sewer gases and unpleasant odors from escaping into the living spaces of a building. This is important for maintaining indoor air quality and ensuring a safe and comfortable environment.

While traps are integral to the drainage system and contribute to preventing backflow in some instances, their main function revolves around blocking odors. Understanding this core purpose helps in recognizing the role traps play in both plumbing systems and overall health and safety standards in residential and commercial buildings.