3.3.5.7.

(1) If access is provided through a fire separation between a storage garage and a Group A, Division 1 or Group B occupancy, the access shall be through a vestibule conforming to Sentence (3).

(2) In a building more than 3 storeys in building height, access through a fire separation between a storage garage and a Group A, Division 2, 3 or 4, or a Group C occupancy, shall be through a vestibule conforming to Sentence (3).

(3) If access is provided through a vestibule, as required by Sentences (1), (2) and 3.3.5.4.(1), the vestibule shall,

(a) be not less than 1 800 mm long,

(b) be ventilated,

(i) naturally to outside air by a vent that has an unobstructed area of not less than 0.1 m² for each door that opens into the vestibule but not less than 0.4 m², or

(ii) mechanically at a rate of 14 m³/h for each square metre of vestibule floor surface area, and

(c) have openings between the vestibule and an adjoining occupancy provided with self-closing doors with no hold-open devices.