W.C. Trap Identification

The primary function of a trap in a Water Closet (W.C.) system is to hold water, creating a seal that prevents foul sewer gases from entering the building.

Trap Selection for W.C.

Among the options provided, the P trap is specifically designed and commonly used for W.C. installations. Its shape allows it to effectively retain water after each flush, maintaining the necessary seal against sewer gases.

Analysis of Trap Options

• P trap: Ideal for W.C.s due to its ability to form a reliable water seal. It connects the W.C. outlet to the waste pipe.
• Gully trap: Typically used outdoors or in specific locations (like floor drains) to intercept surface water and prevent drain entry.
• Nahani trap: Generally used for floor drains in bathrooms or similar areas, preventing sewer gases from ascending through the drain.
• Bottle trap: Commonly found under sinks or wash basins, especially where space is limited.

Therefore, the P trap is the correct choice for a W.C.