R 408.10641 Exit access and discharge.
Rule 641. (1) An exit access must not be through a room subject to locking.
(2) An exit access must be so arranged that it will not be necessary to travel through
any area of high hazard occupancy to reach the nearest exit.
(3) The minimum width of an exit access must be at least equal to the required width
of the exit to which it leads, but not less than 34 inches. The headroom clearance must be
not less than 6 feet 8 inches from the floor.
(4) An exit discharge must discharge directly outside or to a street, walkway, refuge
area, public way, or to a yard, court, or other open space with access to the outside.
(5) Stairs and other exits must be arranged to make clear the direction of egress to
the street. Where an exit stairs continues beyond the floor of discharge, it must be
interrupted at the floor of discharge by a partition, door, or other effective means.
(6) Exit access by the way of an exterior balcony, porch, gallery, or roof must be in
compliance with all of the following:
(a) Be kept free from accumulations of snow and ice.
(b) Be a permanent direct route without obstructions, such as railings, gates, barriers,
or other objects, that might divide the space into sections or rooms. Furniture or other
movable objects must not block the path of travel.
(c) Have no dead ends in excess of 20 feet.
(d) Comply with this standard as to requirements for width and arrangement.
(7) The street, walkway, refuge area, public way, or open space to which an exit
discharge leads must be large enough to accommodate the building occupants likely to
use the exit route.
(8) An exit door must be unlocked.
(9) An outdoor exit route is permitted.
(10) The outdoor exit route must have all of the following:
(a) Guardrails to protect unenclosed sides if a fall hazard exists.
(b) Be covered if snow or ice is likely to accumulate along the route, unless the
employer can demonstrate that any snow or ice accumulation will be removed before it
presents a slipping hazard.
(c) Be reasonably straight and have smooth, solid, substantially level walkways.
(d) Not have a dead-end that is longer than 20 feet (6.2 m).
(11) An exit access must be so arranged that employees will not have to travel
toward a high hazard area, unless the path of travel is effectively shielded from the high
hazard area by suitable partitions or other physical barriers.
History: 1979 AC; 2015 AACS; 2019 AACS.
DOORS AND STAIRS
R 408.10643 Doors; general provisions.
Rule 643. (1) A door assembly, including the doorway, frame, door, and necessary
hardware, may be used as a component in a means of egress when it conforms to the
requirements of this part. As such, the assembly is designated as an exit door.