Back3.4.4.2.(2)

ATTRIBUTION:

Functional Statement:

F12

To facilitate emergency response.

F10

To facilitate the timely movement of persons to a safe place in an emergency.

F05

To retard the effects of fire on emergency egress facilities.

F06

To retard the effects of fire on facilities for notification, suppression and emergency response.

Objective:

OS1.5

 

APPLICATION:

Exits from floor areas above or below the first storey that lead through lobbies, where:
This applies to exits serving floor areas that are intended for occupancies, including mezzanines as stated in Sentence 3.4.2.2.(1), in buildings described in Sentence 1.3.3.2.(1) of Division A.
This also applies to tents and air-supported structures, as stated in Sentences 3.1.6.1.(1) and 9.10.1.2.(1).

INTENT:

To supersede the requirements of Sentence 3.4.4.1.(1) for a rated fire separation and of Sentence 3.4.4.2.(1) prohibiting exits to lead through lobbies, if certain measures are taken.
This is to limit the probability that:
  • excessive height above grade of the lobby will delay fire emergency response operations, which could lead to delays in the evacuation or movement of persons to a safe place, which could lead to harm to persons, including emergency responders,
  • excessive travel distances through the lobby will lead to delays in evacuating, which could lead to harm to persons, and
  • smoke from a fire in a room, premise or interconnected floor space, or a fire in an adjacent occupancy, will spread into the lobby, which could lead to untenable conditions in the exit, which could lead to:
    • delays in the evacuation or movement of persons to a safe place, which could lead to harm to persons,
    • harm to persons, and
    • delays or ineffectiveness in fire emergency response operations, which could lead to delays in the evacuation or movement of persons to a safe place, which could lead to harm to persons, including emergency responders.