§ 107. Public halls. 1. Every public vestibule or other public hall
shall comply either with the provisions of section one hundred
forty-nine for non-fireproof multiple dwellings, so far as applicable,
or with the provisions of subdivision two of this section, except that
the provisions as to ventilation shall not apply to any part of an
entrance hall within sixty feet in a straight line from an entrance
door.

2. If such a dwelling does not comply with the applicable provisions
of section one hundred forty-nine, it shall comply with all of the
following:

a. Every public vestibule or hall shall be everywhere at least three
feet eight inches in clear width.

b. Every such public vestibule or hall shall be separated from all
other parts of the dwelling by fireproof walls.

c. All openings from such a public vestibule or hall to stairs,
fire-stairs, fire-tower balconies, shafts, apartments or suites of rooms
shall be protected by fireproof doors and assemblies, with the doors
self-closing, except that such doors and assemblies shall not be
required in any fireproof class B multiple dwelling for any apartment
consisting of one room opening directly upon a public hall or for any
apartment of three rooms or less in a college or school dormitory.

d. Such a public vestibule or hall shall not be required to have a
window, but if it does not have a window opening to the outer air it
shall be equipped for artificial lighting and be properly lighted at all
times.

e. Except for that part of an entrance hall within sixty feet in a
straight line from an entrance door such a public vestibule or hall
without a window to the outer air shall be ventilated to the outer air
by means of gravity vent flues at least twelve inches in each dimension
or by mechanical means approved by the department. There shall be at
least one vent flue opening of at least twelve inches in each dimension
for each one thousand cubic feet of air content of such public vestibule
or hall. Such vent flues shall be continuous for the height of the
dwelling and the openings at each story shall be equipped with fire
dampers held open by a fusible link at each opening and properly hooded
or provided with louvres at the top above the roof.

f. If a window to the outer air is provided in any such public
vestibule or hall, such vestibule or hall shall nevertheless be
ventilated as provided in paragraph e, except that if such a window has
a glazed area of at least twelve square feet and at least one tenth of
the superficial floor area of the vestibule or hall, readily accessible
to the outer air to the extent of at least five and one-half square feet
of its area, no vent flues need be provided within a distance of forty
feet from each side of such window.

3. The requirements of this section as to ventilation shall apply to
all parts of an entrance hall more than sixty feet distant in a straight
line from an entrance door, to all returns or recesses that lead to
elevators and extend farther from the hall which they adjoin than four
times their width, and to all other returns or recesses from entrance
halls that extend farther than their width.

4. Any part of a public hall that is shut off from any other part of
such hall by a door or doors shall be deemed a separate hall.