What is a p-trap commonly used for?

A p-trap is specifically designed to trap water and create a seal that prevents sewer gases from entering the living space through plumbing fixtures, such as sinks. By holding a small amount of water in its curve, the p-trap effectively blocks these harmful gases while still allowing wastewater to drain away. This function is crucial for maintaining indoor air quality and ensuring the safety of building occupants.

While some other options touch on aspects of plumbing, they misunderstand the primary function of the p-trap. For example, increasing water pressure is managed through different methods and devices, not with a p-trap. Additionally, connecting pipes to the main sewer line involves different types of fittings and joints rather than a p-trap. Regulating the flow of hot water typically utilizes valves or thermostatic controls, which is also separate from the p-trap's purpose. Understanding the specific role of the p-trap clear differentiates its function from these other plumbing elements.