General. All transparent glass doors and fixed adjacent transparent glass sidelights shall be marked as required in these regulations regardless of the type of glazing material used in their construction. Marking of all transparent glass doors and fixed adjacent transparent glass sidelights within 6 feet horizontally shall be of an opaque nature placed as described in §B, of this regulation, and shall be of a design which is readily discernible to any person approaching the doors and sidelights from any direction. Marking Locations. Transparent glass doors and fixed adjacent transparent glass sidelights shall be marked in two areas on the glass surface thereof. One area shall be located at least 30, but not more than 36 inches and the other at least 60, but not more than 66 inches above the ground, floor, or equivalent surface below the door or sidelight. Marking Dimensions. The marking design shall be: At least 4 inches in diameter if circular; 4 inches in its least dimension if elliptical or polygonal; or At least 12 inches in horizontal dimension if the marking is less than 4 inches in its least dimension. The vertical dimension of any marking including lettering may not be less than 1-1/2 inches in height. Marking Methods. Any of the following methods may be used to alert persons to the presence of transparent glass doors and fixed adjacent transparent glass sidelights in their path of movement: Adhesive strips not less than 1-1/2 inches in vertical dimension extending across at least two-thirds of the total glazed area; Decals; Paint, gilding, or other opaque marking materials; Protective grills at least 4 inches wide, extending the full width of the door, at least 30 inches, but not more than 36 inches from the ground, floor, or equivalent surface.