All portable dehumidifiers have a water collection container (tank) to collect the water extracted from the air. These tanks are quite small, to keep the overall size of the dehumidifier down, and need to be emptied at least once a day. Because it may not be convenient, or possible, to empty the bucket daily almost all portable dehumidifiers for home use are designed to allow the water to be drained directly as it is collected. This is known as continuous drainage. In the casing of the dehumidifier a small hole has been cut to allow a small hose to be attached to the dehumidifier through which the water can be drained. The water is drained by gravity alone so for effective continuous drainage the dehumidifier needs to be raised a foot or two above the floor and the hose run to a floor level drain.