A hard hat adapter for a welding helmet is disclosed. The dapater includes a housing which has an outer wall, an interior surface and a bottom surface. The outer wall includes a surface defining a window therethrough. The interior surface includes a recessed surface circumscribing the window. The recessed surface includes at least one planar surface thereon. A rotatable boss is captured within the housing against the interior surface. The boss has an annular lip that includes at least one planar surface thereon configured to selectively engage the planar surface on the recessed surface of the housing and prevent the boss from rotating when engaged thereon and freely rotatable when disengaged therefrom. A mounting post extends from the boss and projects through the window on the housing. The mounting post is configured to selectively couple to a welding helmet. The welding helmet may include a rotatable cam configured to engage a lever arm on the hard hat adapter.
