What does the acronym S trap refer to in plumbing?

The acronym S trap refers to a trap configuration that resembles an "S," used under fixtures. This type of trap is designed to maintain a water seal to prevent sewer gases from entering a building while also allowing wastewater to flow out. The S shape curves upward and then down, creating a water barrier that seals against odors and gases.

Understanding the purpose of an S trap is crucial for effective plumbing design. It is essential in various fixtures, such as sinks, bathtubs, and lavatories, to ensure proper drainage and maintain hygiene within the plumbing system. Proper installation and design also prevent issues like siphoning, where the water seal could be lost due to negative pressure, allowing sewage gases to backflow.

This type of trap is particularly notable in its formative structure, which is vital in residential and commercial plumbing systems. Recognizing its role helps in troubleshooting drainage problems and adhering to plumbing codes that govern the safe and effective installation of fixtures.