Abstract: A post assembly for attaching a worker safety harness to a structure comprises a post member having two transversely spaced wall attachment assemblies at its lower end and on opposite sides thereof and a roof attachment assembly intermediate its ends, the assemblies being releasable to enable the post assembly to be removed while the parts attached to the wall and roof remain for re-use. The assemblies have attachment axes that diverge toward the wall to increase the transverse spacing between the attachment points as the spacing from the wall increases. The spacing of the wall assemblies and their placement on opposite sides of the post ensures that part of any sideways acting force is converted from undesirable shear peeling force to compressive force on one wall assembly and tension force on the other assembly. The part of each attachment assembly that contacts a surface may comprise a central plate with one or more side and/or end plates hinged thereto to accommodate curvature of the roof surface.