Our sample from the COSMOS field in the hydrogen column density, N_H vs. Eddington ratio, λ = L_bol/L_Edd plot, adapted from Fabian et al. (2008). The data points from this work are indicated by black circles, while the red circles are from Brusa et al. (2015a) for the objects where the presence of outflows has been verified (see Sect. 7). Various regions of the plot are divided by the expected Eddington limit curves shown in solid, dashed, and dotted lines representing Galactic dust abundance, 0.3, and 0.1 of the Galactic dust abundance, respectively. The objects in grey regions are expected to have long-lived clouds, while those in the unshaded region are expected to be in a “blow-out” or an outflowing phase.