If you breathe on cold glass, it fogs. And what if you breathe for several hours on the inner surface of the air-mass treatment unit cooled by the water of the Arctic Ocean?
The condensed water could leak into the inhalation hose or onto the oxygen sensors, where we also have drip channels which protect them from water that somehow managed to reach them. Therefore, the bottom of the unit is doubled and shaped so that water which trickles between the two parts of the bottom cannot leak out in any position. If you want to poor out the water after a dive, you just remove the false bottom.
Another place for capturing water that has somehow reached the DSV is the exhalation counterlung. The T-piece, by which the hose is connected to the counterlung, is divided by a partition so that exhaled gas necessarily passes through the counterlung. Gas flows further into the apparatus, but water remains in the counterlung and the diver can expel it using the overpressure valve (circled in red). Thanks to this, it is possible to manage a situation when the diver has removed the DSV from his mouth without having first closed it.