Stripping of oxygen from water using air was performed in four different structured packings. Because the transfer of oxygen to air is easy, the resistance to mass transfer lies on the liquid side. From these experiments, the measured global volumetric mass-transfer coefficient (K(L)a(e)) is equal to the individual mass-transfer coefficient of the liquid phase (k(L)a(e)). The value of the interfacial area a(e) is estimated using a model proposed in 1992, and the individual mass-transfer coefficient of the liquid is deduced and compared to one based on the penetration theory used in the first model proposed for structured packing in distillation columns published in 1985. It was found that the correction factor C-E used to equate both coefficients is close to unity.