A99.     A fire damper shall not be required for the following:

1. Clothes Dryer Exhaust Ducts
2. Hazardous Fume Exhaust Duct
3. Stairwell Pressurization Ducts iv. Smoke Extraction Ducts
4. Laundry and Trash Chutes

A100. Materials used in the construction of a ceiling plenum shall be noncombustible or shall be limited combustible having a flame spread index of not more than 25 and a maximum smoke developed index of 50.

A101. All fire exit staircases that serve the basement floors shall also be pressurized if the same staircase shafts serving the upper floors are pressurized. Fire exit staircases that only serve the basement which have more than 2 levels or more than 7m below the level of discharge (high depth underground buildings and structures) shall be pressurized. Fire exit staircases that only serve the basement which have less than 2 or levels or less than 7m below the level of discharge (low depth underground buildings and structures) shall be provided with mechanical ventilation.

A102. In any building of which the habitable height exceeds 23 m, any internal exit staircases without adequate provision for natural ventilation shall be pressurized.

A103. A single-point injection system shall not be used where the stairwell height is more than eight stories. Stairwells more than 3 storeys above grade or 15m in height, which ever lower shall be provided with multiple-injection systems.

A104. Mechanically ventilated internal corridor shall have a purging rate of at least 6 air changes per hour.

A105. The purge rate for basement shall be at least 9 air changes per hour.

A106. The design smoke layer base shall be above the heads of people escaping beneath it. The minimum height shall be 1830mm

A107. Smoke removal system for firefighting operation shall be provided where there are no natural ventilation openings or where there no operable panels or windows.

A108. Naturally ventilated internal corridor shall be by fixed ventilation openings in an external wall and such ventilation openings being not less than 15 % of the floor area of the internal corridor. Natural ventilation opening shall not be more than 9m from any part of the internal corridor.