Skylights. Existing Tenement Houses. Par. 1. - In every existing tenement house there shall be in the roof, directly over each stair well, a ventilating skylight, provided with ridge ventilators and also with fixed or movable louvres or movable sashes. But this section shall not apply to any tenement house now having windows as provided in section sixty-five or a bulkhead in the roof over the main stairs, which bulkhead is provided with windows made so as to open readily and with not less than twelve square feet of glass in the top of the bulk-head. All skylights hereafter placed in any tenement house shall conform to the provisions of section sixty-six. All the existing dome lights or other obstructions to skylight ventilation shall be removed.

Public Hall - Lighting Of. Par. 2. - Where the public hall in an existing tenement house is not provided with windows opening as provided in section sixty-five, and where there is not a stair well as provided in section sixty-six, all doors leading from such public hall into apartments shall be provided with translucent glass panels of an area of not less than four square feet for each door; or such public hall may be lighted by a window or windows at the end thereof with the plane of the window at right angles to the axis of the hall, said window opening upon the street, a railroad right of way, cemetery, public park, or an alley or open passageway at least ten feet in width, or upon a yard or court of the dimensions hereinbefore provided.