The anchors on the building to which the belt shall be fastened shall be installed in the side frames of the window or in the mullions at a point not less than forty-two inches (42 in.) or more than fifty-one inches (51 in.) above the window sill.
All window frames to which anchors are attached shall be in sound condition and shall be securely fastened in place.
D.C. Mun. Regs. tit. 24, r. 24-3205