Drop size – The size of the radius or diameter of a usually small bulk liquid (μm) which ideally is spherical in shape. Only if the drop has been separated from a larger bulk liquid a drop shape is quickly formed as an unstable state. Drops are separated from the environment by an interphase and their shape is significantly defined by the interphase tension. Under the conditions of the Earth’s gravity, drops, due to their relatively low forces resulting from the interphase tension, are restricted to a great ratio between volume and surface, and so they are of small size which is normally in the millimetre range. STRIKO demisters as knitted wires can be used for drop sizes of approximately 1 µm to 100/120 µm, whereby the separation of larger drops poses no big problem as these simply follow the principle of inertial separation.