In every multiple dwelling erected after April eighteenth, nineteen hundred twenty-nine, every door giving access to an entrance hall from outside the dwelling shall contain at least five square feet of glazed surface. The width of every such door shall be at least seventy-five per centum of the required clear width of such entrance hall as provided in section fifty, except that when a series of such entrance doors is provided their aggregate clear width shall not be less than seventy-five per centum of the required width of the entrance hall and the clear width of each of the doors separately shall be at least two feet six inches. Such a door opening upon a street or a court extending to a street may be of wood. Such a door opening upon a yard or upon a court not extending to a street shall be fireproof. The owner of every multiple dwelling shall install and maintain a light or lights at or near the outside of the front entrance-way of the building which shall in the aggregate provide not less than fifty watts incandescent illumination for a building with a frontage up to twenty-two feet and one hundred watts incandescent illumination for a building with a frontage in excess of twenty-two feet, or equivalent illumination and shall be kept burning from sunset every day to sunrise on the day following. In the case of a multiple dwelling with a frontage in excess of twenty-two feet, the front entrance doors of which have a combined width in excess of five feet, there shall be at least two lights, one at each side of the entrance way, with an aggregate illumination of one hundred fifty watts or equivalent illumination. In enforcing this provision the department shall permit owners to determine for themselves the actual location, design and nature of the installation of such light or lights to meet practical, aesthetic and other considerations, so long as the minimum level of illumination is maintained.