The influence of weeping on the mass transfer of different industrial plates was investigated in a 400 mm inside diameter column equipped with 4 plates. The absorption of acetone from air to tap water was measured on vibrating valve, Nutter valve, Glitch valve, sieve and turbogrid plates with varied weir heights. The weeping was determined by a direct method. The tray efficiency (η) of the investigated plates decreased 1-5% with the increase of weeping rate, while it decreased 10-25% with the increase of weir height. Mass transfer characteristics of the above plates, namely recovery efficiency (E), volumetric mass transfer coefficient (KGa) and pressure drop related to one theoretical plate (Δp/Nth) were measured and compared.