Fire Safety
ScopeThis section details the requirements to be provided in air conditioning systems to prevent the spread of Fire and Smoke to comply with the current requirements of the Chief Inspectorate of Fire Services.
Fire Damper
Wherever ducts pass through fire walls or connect to fire areas of a building, automatic fire dampers shall be installed in the positions indicated on the drawings.The fire dampers shall be manufactured to comply with Australian Standard 1682 and tested and approved by the relevant standards authority in Australia. In addition the fire dampers shall be approved by the Chief Inspector of Fire Services. All locally manufactured fire dampers shall be individually certified by the Principals.
The fire resistance rating of the Dampers shall be as shown on the drawings. The dampers shall be either single blade or multiple blades, construction depending on the size. The dampers shall be installed in the Fire Walls to the requirements and specification of the manufacturers and the satisfaction and approval of performance. The attachment of the damper to the ducting shall be done in such a manner, that any deformation or collapse of the ductwork under fire conditions shall not dislodge the damper or affect its operation or performance.
The fire dampers shall be installed in such a manner so that the casing completely penetrates the wall and has the following features.
i. The damper shall penetrate the wall and shall be retained on both sides by means of flanges in such a manner that it can expand under fire conditions without distorting the blades in the closed position.
ii. Alternatively it shall be flanged only on one side (the accessible side) and it shall be fixed to the damper and to the wall through slotted holes to allow expansion.
The retaining flange(s) shall be butted against the face of the wall and fixed to the damper casing.
The clearance between the damper body and the sides of penetration shall not be greater than half the width of the angles section of the retaining flanges.
The space between the damper body and the opening in the wall shall be filled with an approved compressible non-combustible material for the full thickness of the wall.
The Fire Damper shall be installed in such a manner so as to ensure that the direction of air flow does not impede the closure of the damper.
The supplier of the Fire Damper shall certify that the damper installation is to their satisfaction and requirements of the principal.
Ducting Components
Flexible ducts of combustible material may only be used in the supply side of the system. Such connections shall not exceed 5000mm in length.
The material used shall meet the following requirements:-
a. A speed of flamed index of not greater than 0.
b. A smoke developed index not greater than 3.
Flexible connections to return air system, ducts, ducts supplying pressurized stairs etc shall be of approved non-combustible materials.
Duct Insulation
Internal lining of ducts when not encased in un-perforated metal sheeting the material used for internal lining adhesives and protective coatings or wrapping shall comply with the requirements stated in Clause 8.3.2. (a) and (b) above.Exhaust Fans
Smoke Spill Exhaust Fans shall be supplied and installed at the locations shown on the drawings, to the sizes and capacities indicated.The materials of the Fan housing, blades bearing etc shall be made of materials to ensure that it can operate continuously for 3 hours in an ambient temperature of 250°C.
The motors shall be of the totally enclosed squirrel cage induction type, fitted with ball bearings of generous size. The motor shall comply fully with BS170 or BS2613. The insulation shall be Class H to BS2757.
The Air Handing Unit switchboard on each floor shall incorporate the necessary contactors such that, in the event smoke is detected by the smoke detector in the Air Handing Unit Room, the Air circulation fan shall be shut off and the smoke spill fan/s on that floor shall start automatically to extract smoke from that floor.
The Sub-Contractor shall supply and install the smoke spill fan control and indicator panel at the main control room at the position shown on the drawings. The smoke spill fan control and indicator panel shall consist of manual stop/start buttons and fan run/trip indicator lamps for all the smoke spill fans - four numbers being grouped into one zone. The Sub-Contractor shall liaise with the Fire Protection System Contractor in respect of the Indicator Lamps and control switches so as the maintain uniformity. All wiring from the main control room at ground floor to the smoke spill fans and to the Air Handing Unit shall for part of this contract.
Note:
The Main Annunciator Panel (cubicle only) at the Main Control Panel will be provided by others but the Sub-Contractor shall liaise with this supplier in respect of installation of smoke spill fan control and indicator panel on the main annunciator panel.
Staircase Design Calculation
Pressurization systems shall be provided to all protected lobbies and staircases as indicated on the drawings. The quantities, locations, capacities and sizes of the fans shall be as shown on the drawings.The fans shall be capable of maintaining a constant pressure difference of maximum 2”. Water gauge across the pressurised area and non-pressurized area.
The air volume delivered shall be controlled by means of electric actuators and the air volume shall be controlled by means of variable pitch blades of the fan.
The actuators shall be an integral part of the hub-assembly.
The pressure differential between the pressurized area and non-pressurized area shall be measured by means of a pressure differential gauge.
The Sub-Contractor shall supply and install the pressurization fan indicator panel at the main control room at the position shown on the drawings. This indicators panel shall consist of run/trip indicator lamps and remote stop button. Uniformity of lamps shall be maintained. The Sub-Contractor shall liaise with the Main Annunciation panel Supplier in respect of the installation of Pressurization Fan indicator panel on the Main Annunciator Panel.
Note:
The Control Wiring (only) from the Main Fire Alarm Panel to the Pressurization Fan shall be brought by Fire Protection System Contractor but the termination work shall be carried out by this Sub-Contractor.