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We study the impact of neutral hydrogen absorption on ${\rm H_2}$photodissociation in protogalactic haloes exposed to soft-UV radiation.Lyman-series absorption can significantly deplete dissociating photons as lineoverlap with the ${\rm H_2}$ Lyman-Werner bands occurs for neutral columndensities exceeding $10^{22}$ ${\rm cm^{-2}}$, but this effect has not beenpreviously included in studies of protogalactic haloes. We use high-resolutionthree-dimensional hydrodynamic simulations to investigate this "HI-shielding"in three metal-free atomic cooling haloes collapsing at redshift $z \sim10-20$. We use CLOUDY modeling to update a previous fitting formula forHI-shielding which is a better model for shielding of non-ground state ${\rmH_2}$ rovibrational populations and implement the new fit in our simulations.We find that the inclusion of HI-shielding increases the "critical flux" forsuppression of ${\rm H_2}$ cooling in these haloes by $\sim 60-100$ per cent.The larger critical flux has implications in particular for the predictednumbers of candidate haloes in which "direct collapse" could seed massive($\sim 10^5$ ${\rm M_\odot}$) black holes at $z \sim 15$.

HI-shielding of ${\rm H_2}$ in UV-irradiated protogalaxies: suppression of the photodissociation rate