SS Drain Traps

A drain trap is the fitting set into the floor where water from washing and cleaning leaves the room. Inside it, the outlet path dips and rises again, so a small pool of water always stays in the trap. That standing water, called the water seal, blocks air, odours, insects and drain-borne contamination from rising back out of the drainage line into the room.

The seal only works while there is water in it. In a floor drain that is used rarely, the water slowly evaporates and the seal is lost, letting drain air into the room. That is why infrequently used drains need a routine: top them up, or close them with a sealing cap when they are not in use. A removable strainer basket catches debris before it reaches the pipe, and a perforated plate or a solid cover sits on top, depending on whether the drain is open or closed.

In pharmaceutical plants, drains need particular care. GMP guidance for sterile manufacturing, such as EU GMP Annex 1, says sinks and drains should not be installed in the cleanest grade A and B areas. In lower-grade cleanrooms and wash areas, floor drains should have traps or water seals designed to prevent backflow, and should be cleaned, disinfected and maintained on a schedule. A drain trap made in stainless steel, with parts that come apart for cleaning, makes that routine practical.

Our SS drain traps are made in SS 304 with a matt or mirror finish. Round traps are made in 6 inch and 9 inch diameter, and square traps in 8 inch and 12 inch. Each comes with a cover plate with handle, a perforated plate and a round inner cup (dibbi) with a gasket. The top frame has a flange that sits into the floor, and the outlet adaptor gives a leak-proof joint to the drain line. As a guide, water flows through our 8 inch square trap at about 3.5 litres per second; the actual rate depends on the liquid and the trap size.

A good drain trap is one that cleaning staff can strip, clean and refit without tools or effort. The strainer basket lifts out, the plates lift off and the seal ring can be checked and replaced, so nothing stays hidden in the trap between cleaning cycles.