The latter can be a serious problem because water deposited on the crop and the building structure can cause disease, rotting or structural damage. This equipment consists of a pad of material which is saturated with water and through which air is blown. Although control is still difficult, there is no problem with droplet carry-over at high humidification rates. In practice this means that the humidifier can be operated continuously without any risk of water carry-over damage. Pad humidifiers can either be built into an air handling system or bought as stand alone units.
Energy costs are low as the only power required is that to operate the fan and water pump.
Installation is simple involving an electrical connection and a water supply. Stand alone humidifiers can be positioned anywhere in the store but preferably at a high level. Humidities taken for 50C. Note that the effect of humidity depression is much greater at higher temperatures.