§ 231. Egress. 1. Every non-fireproof tenement exceeding two stories
in height and every fireproof tenement erected after May sixteenth,
nineteen hundred thirteen, shall have at least two independent means of
egress, which shall extend from the ground story to the roof, be located
remote from each other and be separated from each other by walls.

2. One of such means of egress shall be a flight of stairs constructed
as provided in sections two hundred thirty-three to two hundred
thirty-eight inclusive; but this sentence shall not be construed to
require any alteration in the material or width of any stair or its
treads and risers lawfully permitted on April eighteenth, nineteen
hundred twenty-nine.

3. The other required means of egress shall be directly accessible at
each story to each apartment without having to pass through the first
means of egress. Such other means of egress shall be any one of the
following, as the owner may elect:

a. A system of outside fire-escapes constructed as provided in section
fifty-three.

b. An additional stair, either inside or outside, constructed and
arranged as provided in sections two hundred thirty-three to two hundred
thirty-eight inclusive.

c. A fire-tower or fire-stair constructed and arranged as provided in
section two hundred thirty-nine.

d. Except as provided in subdivision nine of section fifty-three, any
means of egress lawfully permitted on April eighteenth, nineteen hundred
twenty-nine, except wire, chain, cable, vertical ladder, or rope
fire-escapes.