trap

sewage system

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Last updated

July 14, 2026

Quick Summary

A P-trap is a U-shaped fixture used in sinks and lavatories as part of a plumbing system. Its primary function is to retain a small amount of water, creating a seal that prevents foul sewer gases from entering the building. This water seal is crucial for maintaining sanitary conditions within the plumbing system. The term "P-trap" refers to its distinctive shape, designed to trap this water effectively. These traps are essential components of waste disposal systems within buildings, working in conjunction with drainage and venting systems to ensure the safe removal of wastewater.12

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construction
Plumbing
…a semicircular reverse curve, or trap, which remains constantly filled with water and prevents odors from the drainage system from escaping into occupied spaces. Immediately downstream from each trap is an opening to a vent pipe system, which lets air into the drainage system and protects the water seals in…
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…a semicircular reverse curve, or trap, which remains constantly filled with water and prevents odors from the drainage system from escaping into occupied spaces. Immediately downstream from each trap is an opening to a vent pipe system, which lets air into the drainage system and protects the water seals in…
Read More