§ 59. Ventilation for shafts. 1. There shall be provided in the roof
directly over each stair, fire-stair, dumbwaiter, elevator or similar
shaft which extends to or within one story of a roof, a ventilating
metal skylight of the cross-sectional area of such shaft. Such skylight
need not, however, exceed twenty square feet in area. Where an existing
skylight is smaller than the dimensions or area prescribed in this
subdivision, no structural change shall be required, but a ventilating
metal skylight fitting the existing opening in the roof shall be
sufficient. Every skylight shall be glazed with plain glass in the roof
of such skylight and shall be equipped with metal screens over and under
the skylight. In lieu of a skylight a window of the same area at the top
story shall be accepted.

2. Whenever there is a flooring of solid construction at the top of
any enclosed stair, fire-stair, elevator or similar shaft, openings
shall be left near the top of such shaft for ventilation. Such openings
shall provide at least two hundred eighty-eight square inches of
unobstructed ventilation and shall communicate directly with the outer
air, or be otherwise ventilated in accordance with the provisions of the
local building code.

3. It shall be unlawful to discharge into any such shaft any
inflammable or volatile gases, liquids or other thing or matter which
would endanger life.