7.1.1 General
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Explanations & Illustrations
Clause 7.1.1 : General
( No illustration )
The term “air conditioning” has been defined by the American Society of Heating, Refrigerating, and Air Conditioning Engineers as:
“Air conditioning is the process of treating air so as to control simultaneously its temperature, humidity, cleanliness and distribution to meet the requirements of the conditioned space”.
The use of air-conditioning and mechanical ventilation systems will invariably, except for self-contained split units, involve some use of pipe works and ducts for air distribution and removal.
The use of ducts present the inherent possibility of spreading fire, heat, gases and smoke throughout the building or the floors/areas served.
Where air-conditioning system is designed to operate during fire emergency, it is to be emphasized that the system shall comply with all the relevant requirements for the mechanical ventilation system in this Code.
Where an air-conditioning system is provided in lieu of a mechanical ventilation system for emergencies, all the requirements specified in this Code for mechanical ventilation systems shall apply to the air-conditioning system.
7.1.2 Construction of ductwork
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Explanations & Illustrations
Clause 7.1.2 : Construction of ductwork
Figure 7.1.2
Insulation material/barrier lining and adhesives shall have minimum Class 1 flame spread rating. Where ceiling construction requires Class 0, covering and lining insulation material shall also be Class 0. Where combustible material is used for the insulation of the duct, it shall be kept at least 1000mm away from a fire damper in order to prevent premature closing of the damper arising from a fire from the combustible insulation material. For flexible joints and connections which are combustible, there is a need to limit the length of the joints and connection to max. 250mm and 4m respectively.
Ducts for air-conditioning and mechanical ventilation systems shall be constructed in compliance with all of the following requirements:
a. Materials
Air-conditioning or other ventilation ducts, including framing thereof, shall be constructed of steel, aluminium, glass fibre batt or mineral wool batt or other approved materials.
b. Support
Air-conditioning or other ventilation ducts shall be adequately supported.
c. Duct linings & coverings
Duct covering and lining shall be non-combustible. However, if it is necessary to use combustible material, it shall:
(1) when tested in accordance with methods specified in this Code, have a surface flame spread rating of not lower than Class 1, except in areas of a building where Class 0 flame spreading rating is required for the ceiling construction under this Code, a Class 0 rating for the covering and lining materials shall instead be required;
(2) when involved in fire, generate a minimum amount of smoke and toxic gases; and
(3) be at least 1m away from a fire damper.
d. Flexible joints and connections
(1) Flexible connections at the ends of ventilation ductwork connecting terminal units, extract units and ventilation grilles shall not exceed 4m.
(2) Flexible joints, which are normally provided to prevent and/or allow for thermal movements in the duct system, shall not exceed 250mm in length.
(3) Flexible joints shall be made of material classified as ‘not easily ignitable’ when tested under BS 476: Part 5.
e. Duct enclosure
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Explanations & Illustrations
Clause 7.1.2e. : Construction of ductwork
( No illustration )
A protected shaft used for the enclosure of services shall comply with the following:
a. The protecting structure for protected shaft containing kitchen exhaust duct and mechanical ventilation ducts serving areas specified in Cl.5.2.1g.(1)(a),
(b), (c),
(i) and Cl.5.2.1h. which passes through one or more floors shall be masonry. Such shaft shall be completely compartmented from the rest of the shaft space containing other ducts or any other services installations.
b. For protected shaft containing ducts serving other areas which passes through two or more floors shall be constructed of fire-rated material.
Enclosure of ducts shall comply with the requirements in Cl.3.8.9a..
f. Ductwork through smoke-free or fire lift lobbies
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Explanations & Illustrations
Clause 7.1.2f. : Construction of ductwork
Section
Figure 7.1.2f. - 1
In addition to providing fire-rated enclosure to the duct within the lobby, fire damper is fitted where the duct penetrates the lobby enclosure. Should a fire penetrates the fire damper, it will still be contained within the duct.
Section
Figure 7.1.2f. - 2
The omission of fire damper to the duct where it penetrates the lobby enclosure is acceptable if a masonry slab is constructed below the duct to act as compartment ceiling. The masonry slab over the lobby completes the compartmentation making the lobby a safe area.
Figure 7.1.2f. - 3 : Routing of ventilation ducts directly from AHU room to office space
With proper pre-planning, ventilation ducts are routed directly from the AHU rooms to occupancy areas, thus avoiding the routing through the protected lobby.
Figure 7.1.2f. - 4 : Routing of ventilation ducts along protected lobby
Ventilation ducts are routed along the smoke-stop lobby to serve office 2 & 3. Routing the ventilation ducts through the fire lift or smoke-stop lobbies should be avoided. “Unavoidable situations” where ventilation ducts were routed through the fire lift or smoke-stop lobbies referred to existing building where physical constraints existed making it difficult to route the ventilation duct through other spaces other than the lobby area.
Ventilation ducts should not pass through smoke-free or fire lift lobbies. Where unavoidable, the part of the ventilation duct within the lobby shall be enclosed in masonry construction with fire resistance rating at least equal to that of the elements of structure. If other forms of fire resisting construction are used, a fire damper shall be fitted where the duct penetrates the lobby enclosure.
g. Ductwork through separating walls
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Explanations & Illustrations
Clause 7.1.2g. : Construction of ductwork
Axonometric section
Figure 7.1.2g. - 1
A separating wall is a division wall that separate adjoining buildings of different ownership. Ducts are prohibited to penetrate separating wall to prevent fire spread from one building to another.
2nd storey floor plan
Figure 7.1.2g. - 2
In terrace shophouses, there should be no sharing of air-con ducts.
No air-conditioning or ventilation duct shall penetrate separating walls.
(1) Where proprietary fire-rated materials are used to construct the fire-rated duct, the fire rating of the fire-rated duct shall have the same period of fire resistance as the wall or floor it penetrates.
(2) Proprietary fire-rated duct shall be tested to BS 476 Part 24 or equivalent and its usage be approved by the SCDF.
(3) Running of non-fire-rated duct and/ or other building services above the proprietary fire-rated duct should be avoided. When unavoidable due to physical constraints, the supports to such non-fire-rated duct and/ or other building services running above the proprietary fire-rated duct shall be strengthened, such that the tensile stress generated on the supports shall not exceed 10N/mm2. The non-fire-rated duct and/ or building services shall also be adequately protected to prevent collapse in a fire which will otherwise affect the stability of the proprietary fire-rated duct below.
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Explanations & Illustrations
Clause 7.1.2h.(3) : Construction of ductwork
.tmb-firecode.png?Culture=en&sfvrsn=1c7cec5a_1 "Fg.7.1.2h(3)")
Section
Figure 7.1.2h.(3)
(4) Fans forming part of a fire-rated duct shall also be enclosed in the same fire-rated enclosure.
i. Control panel
Effective Date: 1 Sep 2021
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Rationale - Clause 7.1.2i
The control panel serving the fans of smoke control systems are crucial and should not be located within any smoke layer to ensure that the integrity of the smoke control system is not compromised in an fire emergency. The exhaust systems would not be operable in the event of failure of the control panels.
Amendment History
| 7.1.2i |
1 Sep 2021 |
1 Sep 2021 |
Clarification |
7.1.2h.(5) Control panels serving engineered smoke control and smoke purging systems shall be clearly visible and located within a common location readily accessible for operation and maintenance, preferably within circulation space, with a mounting height of not less than 1.5m or more than 1.8m from the finished floor level. For smoke purging systems in car parks, the control panel shall be sited at least 1.5m away from any car park lot or other fire hazards. If a common accessible location is not possible, the control panels shall be protected with at least 1-hr fire resistance rating. |
1 Sep 2021 |
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(1) The location and placement of control panels serving engineered smoke control and smoke purging systems shall be located within a common space such that the panels are clearly visible and readily accessible for operation and maintenance. Control panel shall be mounted at a height not less than 1.5m or not more than 1.8m from the finished floor level.
(2) For control panels serving smoke purging systems, it shall be located at least 1.5m away from fire hazards e.g. control panels for smoke purging system in carparks sited away from vehicle parking lots. Alternatively, the control panel shall be protected with at least 1-hr fire resisting rating enclosure.
Amendment History
| 7.1.2i |
1 Sep 2021 |
1 Sep 2021 |
Clarification |
7.1.2h.(5) Control panels serving engineered smoke control and smoke purging systems shall be clearly visible and located within a common location readily accessible for operation and maintenance, preferably within circulation space, with a mounting height of not less than 1.5m or more than 1.8m from the finished floor level. For smoke purging systems in car parks, the control panel shall be sited at least 1.5m away from any car park lot or other fire hazards. If a common accessible location is not possible, the control panels shall be protected with at least 1-hr fire resistance rating. |
1 Sep 2021 |
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7.1.3 Pipework
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Explanations & Illustrations
Clause 7.1.3 : Construction of ductwork
Section
Figure 7.1.3 - 1 : Metal pipes with combustible insulation
Section
Figure 7.1.3 - 2 : Metal pipes with non-combustible insulation
Section
Figure 7.1.3 - 3 : : Plastic pipes with non-combustible insulation
Minimum Class 1 for insulation material/barrier lining and adhesives. Where ceiling construction requires Class 0, insulation material shall also be class 0. However, the use of 10mm to 15mm max. pipe works for split unit system would be considered as acceptable.
The use of fire collar shall be appropriate for the diameter of the PVC/UPVC pipe and shall be duly secured to the surface of the wall or floor with steel anchor bolts.
Insulation for pipework associated with the air-conditioning and mechanical ventilation systems shall comply with the following requirements:
a. Flame spread rating
Insulation material for pipework, together with vapour barrier lining and adhesives shall, when tested in accordance with the methods specified in this Code, have a surface flame spread of not lower than Class 1. However, in areas of buildings where Class 0 flame spread is required for the ceiling construction under this Code, a Class 0 rating for the insulation material shall be required.
b. Plastic and foam rubber insulation
Notwithstanding the requirements of Cl.7.1.3a., the use of plastic and foam rubber insulation materials of a lower classification is permitted if:
(1) it is of the self-extinguishing type; and
(2) the insulation is covered by or encased in a metal sheath or hybrid plaster or other non-combustible cladding material,
provided that any opening in the element of structure or other part of a building penetrated by the pipework shall be effectively fire-stopped by replacement of the insulation material at the junction of penetration with fire resistant material having equal fire resistance rating. A fire-rated proprietary pipework system can be used if it is tested in the manner acceptable to the SCDF.
7.1.4 Air plenum
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Explanations & Illustrations
Clause 7.1.4 : Air plenum
Section
Figure 7.1.4 - 1 : Concealed ceiling space
Section
Figure 7.1.4 - 2 : Concealed space below raised floor
The main reasons for imposing additional fire safety requirements are that a fire occurring in the concealed space would be difficult to detect and that smoke and heat would quickly spread beyond the concealed space.
Sprinkler system is usually not provided in the concealed space, hence, all the supports for the raised floor or ceiling membrane shall be of non-combustible material. Ceiling plenum provides the means for transferring heat, smoke and fire, hence there should be a very strict control on the amount of combustible materials in it.
Section
Figure 7.1.4 - 3 : Return air in ceiling space
Section
Figure 7.1.4 - 4 : Return air plenum in concealed space below raised floor
A fire occurring in the concealed space would be difficult to detect. The smoke and heat could quickly spread beyond the origin of fire in the concealed space.
To restrict the unseen spread of smoke and heat in concealed spaces, additional fire safety requirements are imposed under Cl.7.1.4a. and Cl.7.1.4b..
Section
Figure 7.1.4 - 5
Section
Figure 7.1.4 - 6
Figure 7.1.4 - 7
Section A-A
Figure 7.1.4 - 8
Low-flame and low-smoke plenum rated PVC cables conforming to NFPA 262 are permitted to be run exposed in plenum, provided that the plenum shall be protected by sprinkler system or gaseous total flooding system.
In the case of Fan Coil Unit (FCU) or Air Handling Unit (AHU) using plenum for air return and serving more than one rooms, it shall be provided with smoke detection at the return air plenum. This is to address smoke detection within the air plenum space.
A concealed space between the ceiling and floor above it, ceiling and roof, or raised floor and structural floor of a building can be used as a plenum provided:
a. The concealed space contains only:
(1) mineral insulated metal sheathed cable, aluminium sheathed cable, copper sheathed cable, rigid metal conduit, enclosed metal trunking, flexible metal conduit, liquid tight flexible metal conduit in lengths not more than 2m, or metal-cladded cables;
(2) electric equipment that is permitted within the concealed spaces of such structures, if the wiring materials, including fixtures, are suitable for the expected ambient temperature to which they will be subjected;
(3) other ventilation ducts complying with Cl.7.1.2a. to d.;
(4) communication cables for computers, television, telephone and inter-communication systems;
(5) fire protection installations; and
(6) pipes of non-combustible material conveying non-flammable liquids.
b. The supports for the ceiling membrane are of non-combustible material.
c. Exception
Low-smoke and low-flame plenum rated PVC cables conforming to NFPA 262 can be run exposed in plenum, provided that:
(1) the plenum space is protected by a sprinkler system or gaseous total flooding system; and
(2) a FCU or AHU using a plenum for air return and serving more than one room, is installed with smoke detector(s) at the return air plenum space to shut down the FCU/ AHU upon detection of smoke.
Any fire damper shall have a fire resisting rating of not less than that required for the compartment wall or compartment floor through which the relevant section of the ventilation duct passes. Fire dampers shall be of the type approved by the SCDF and constructed in accordance with the requirements in SS 333.
a. Provision of fire dampers
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Explanations & Illustrations
Clause 7.1.5a. : Fire dampers
Section
Figure 7.1.5a. - 1
Exposed ventilation duct is not fire-rated. Fire damper is provided where it passes through the compartment floor or wall to prevent fire spread from compartment to compartment via the duct.
Section
Figure 7.1.5a. - 2
To prevent fire spread from compartment to compartment via the duct, fire damper shall be provided at the inlets to the exhaust air shaft and outlets from supply air shaft.
The dampers shall be properly secured to the protecting structure or protected shaft to prevent any displacement. The method of installation shall follow the type tests shown in the test report issued by testing laboratory.
Fire dampers are provided to inlets of exhaust air shafts and outlets of supply air shaft
Figure 7.1.5a. - 3
Ventilation ducts which pass directly through a compartment wall or compartment floor shall comply with the following:
(1) where the ventilation duct does not form a protected shaft or is not contained within a protecting structure, the duct shall be fitted with a fire damper where it passes through the compartment wall or compartment floor; and
(2) where the ventilation duct forms a protected shaft or is contained within a protecting structure, the duct shall be fitted with fire dampers at the shaft inlets and outlets.
b. Installation of fire dampers
(1) Fire dampers shall be installed so that the casing completely penetrates through the compartment wall or floor, and the casing shall be retained, either:
(a) 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, or
(b) on the accessible side by means of one flange only, which can be fixed to the damper and to the wall through slotted holes to allow for expansion.
(2) Flanges shall be butted against the face of the compartment wall or floor and fixed to the damper casing.
(3) Ductwork connected to the damper shall be attached in such a manner as to ensure that the damper remains securely in position and is fully functional in the event of damage of ductwork.
(4) The clearance between the damper body and the sides of the penetration shall not be less than that of the tested prototype and be not greater than half the width of the angled section of the collar.
(5) The space between the damper body and the opening in the wall or floor shall be fire-stopped.
(6) Vertically positioned fire dampers shall be installed in such a manner that the direction of air flow assists in the closure of the damper.
(7) Connections to fire dampers
The distance between the plane through a closed fire damper and ducting, flexible connections, duct coverings, internal linings and the like, shall be
(a) not less than 1m when such parts are made of materials with fusing temperatures less than 1000oC;
(b) not less than three times the diagonal or diameter of the damper; and
(c) not less than 2m when such parts are made of materials that are combustible, except for vapour barrier to provide thermal insulation.
(8) Fire damper inspection access doors
Each fire damper installation shall be provided with an inspection access door in the ventilation duct, either upstream or downstream, as appropriate. The access door dimension shall measure 450mm (length) X 450mm (width); for smaller ducts, the door width dimension can be reduced to the width or depth of the duct. Access doors shall be hinged and fitted with sash locks, and be constructed of minimum 1.25mm suitably braced sheet steel. Openings in ducts shall be stiffened by a sheet steel frame.
c. Prohibition of fire dampers
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Explanations & Illustrations
Clause 7.1.5c. : Fire dampers
Figure 7.1.5c. : Car park smoke purging system
Fire dampers shall not be fitted in any of the supply air shaft or extract air shaft. The smoke purging system would fail as the fire dampers when in closed position would prevent movement of air within the shaft.
Fire dampers shall not be provided in the following locations:
a. openings in wall of a protected shaft serving kitchen exhaust;
b. anywhere in the supply duct work of air pressurising system to exit staircase; and
c. anywhere in the supply and exhaust ducts serving fire pump room, generator room, FCC and flammable store.
Fire dampers shall not be fitted in any of the following locations:
(1) openings in walls of a smoke extract shaft, or a return air shaft which also serves as a smoke extract shaft, or
(2) openings in walls of a protected shaft when the openings have a kitchen exhaust duct passing through it, or
(3) opening in walls of a protected shaft when the openings have a fume hood exhaust duct passing through it, or
(4) anywhere in an air pressurising system, or
(5) in locations explicitly prohibited in this Code.
d. Standards
Where a fire damper is required by this Code to be installed in an air- conditioning and mechanical ventilation system, its type, details of installation, connection of accessories, inspection door, etc., shall be in accordance with SS 333.
7.1.6 Fire resisting floor ceiling and roof ceiling
a. The space above a suspended ceiling which forms part of a fire-rated floor ceiling or roof ceiling construction shall not contain ducting, unless said ducting was incorporated in a prototype that qualified for the required fire resistance rating, in which case the ducting shall be identical to that incorporated in the tested prototype.
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Explanations & Illustrations
Clause 7.1.6a. : Fire resisting floor ceiling & roof ceiling
Figure 7.1.6a. : Ducting above fire-rated ceiling or roof ceiling construction
Mechanical ventilation ducts are not permitted to be located in the concealed space of fire-rated floor ceiling or roof ceiling assembly, unless such ducts are included in the prototype that was tested for the required fire resistance rating. The type of ducting within such ceiling or roof spaces as well as details of openings in such ceiling shall be identical to that incorporated in the tested prototype.
b. Openings in the ceiling, including openings to enable the ceiling to be used as a plenum, shall be protected by fire dampers identical to those used in the tested prototype. Such openings in the ceiling shall be so arranged that:
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Explanations & Illustrations
Clause 7.1.6b. : Fire resisting floor ceiling & roof ceiling
Figure 7.1.6b.
1. Area of each opening (A & B) shall not be greater or larger than that in the prototype test panel.
2. Total area of openings (A & B) for ceiling to each compartment shall not be greater than that of the prototype test panel.
3. The opening (A & B) can be relocated within the ceiling area provided the proximity to structural member, e.g. column, beams and structural walls is not less than that in the prototype test panel.
(1) no opening is greater in area than that in the corresponding prototype test panel;
(2) the aggregate area of the openings per unit ceiling area does not exceed that of the prototype test panel; and
(3) the proximity of any opening to any structural member is not less than that in the prototype test panel.
7.1.7 Locations of intakes and return air openings
a. Openings for the intakes of outdoor air to all air handling systems, mechanical ventilation systems, pressurisation systems of exit staircases and internal corridors, and smoke control systems shall be no less than 5m from any exhaust discharge openings.
b. All return air openings and outdoor air intakes shall be located and arranged such that sources of ignition, such as lighted matches and cigarette butts, which accidentally enter the openings and intakes cannot be deposited onto the filter media.
7.1.8 Air handling unit (AHU) room
a. Air plenums
Air handling systems shall not use protected shafts of exits, smoke-free lobbies, including its concealed space for supply, exhaust or return air plenums.
b. Compartmentation
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Rationale - Clause 7.1.8b
Rooms having no usage other than housing air handling equipment or package units, and their associated electrical controls are typically not regarded as areas of high risk and therefore compartmentation is not required. However, fire dampers shall be provided within the air ducts of the air handling equipment where they penetrate through compartments to prevent fire spread.
(1) Where the air handling equipment serves more than one compartment, fire dampers shall be provided in air ducts at penetrations through the compartment walls and floors to comply with the requirements in Cl.7.1.5.
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Explanations & Illustrations
Clause 7.1.8b.(1) : Air handling unit room
.tmb-firecode.png?Culture=en&sfvrsn=293dcbe3_1 "Fg.7.1.8b(1)")
Figure 7.1.8b.(1)
Where the AHU serves more than one compartment, fire dampers shall be provided in air ducts at penetrations through the compartment walls and floors.
(2) Where AHU rooms are vertically stacked, each AHU room shall be separated by a compartment floor at every level.
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Explanations & Illustrations
Clause 7.1.8b.(2) : Air handling unit room
.tmb-firecode.png?Culture=en&sfvrsn=f7cee770_1 "Fg.7.1.8b(2)")
Figure 7.1.8b.(2)
1. Some practice of using fire-rated ceiling at the underside of the metal platform for vertically stacked AHU rooms which will likely deteriorate over time due to moisture or dampers, is no longer permitted.
2. Vertically stacked AHU rooms shall be separated by a compartment floor at every level.
c. Smoke detectors
(1) Smoke detectors of approved type shall be incorporated in the return air stream immediately adjacent to:
(a) AHUs serving more than one storey or compartment, or
(b) a single AHU in excess of 15000m³/h.
(2) The function of smoke detectors, where required by this Code, is to initiate action to shut down the AHU automatically when the smoke density in the return air system has become unacceptable for recycling.
d. Stop switch
Where the AHUs in a building are not centrally controlled, each AHU exceeding 8500m³/h shall be provided with a manual stop switch to facilitate quick shutting down of the fan in the case of fire. For ease of access, this switch shall be located on the wall next to the door opening of the air handling equipment room.
7.1.9 Ventilation system for exits
Effective Date: 25 Aug 2023
a. Air plenums
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Explanations & Illustrations
Clause 7.1.9a. : Ventilation system for exits
Section
Figure 7.1.9a..
The protection of these spaces as means of escape is important. They must not be used as air plenum by other systems.
Protected shaft of exits, smoke-free lobbies, including their concealed spaces shall not be used for supply, exhaust or return air plenum of air handling systems.
b. Exit staircase and internal exit passageway
A mechanical ventilation system for each exit staircase and internal exit passageway, if provided, shall be an independent system of supply mode only exclusive to the particular staircase and internal exit passageway, and it shall comply with all of the following requirements:
(1) Supply air for the system shall be drawn directly from the external space, with intake point not less than 5m from any exhaust discharge openings.
(2) For exit staircase serving more than four storeys, supply air shall be conveyed via a vertical duct extending throughout the staircase height and discharging through outlets distributed at alternate floors.
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Explanations & Illustrations
Clause 7.1.9b.(2) : Ventilation system for exits
.tmb-firecode.png?Culture=en&sfvrsn=58cd2ff2_1 "Fg.7.1.9b(2)")
Section
Figure 7.1.9b.(2).: Mechanical ventilation to exit staircase and internal exit passageway
There is a need to separate supply air fan from the exhaust louvres by at least 5m measured from the edge of the exhaust louvres housing. This is to prevent the possibility of smoke being drawn into the supply air shaft. The exhaust louvres (outlet) shall not face directly to any inlet of air supply.
For maintaining uniformity of air distribution in the staircase it would be desirable to place the supply air outlet at every floor level, but should not be more than alternate floors. The supply air system to the staircase shall be an independent system as it is expected to operate during emergency to provide smoke free environment to serve occupants evacuating in the staircase.
(3) Where the supply air duct serving the exit staircase has to penetrate the staircase enclosure, the portion of the duct where it traverses outside the staircase shall be enclosed in masonry construction or drywall complying with Cl.3.8.7b. of at least the same fire resistance as the elements of structure, and it shall not be fitted with fire dampers.
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Explanations & Illustrations
Clause 7.1.9b.(3) : Ventilation system for exits
.tmb-firecode.png?Culture=en&sfvrsn=f81ef524_1 "Fg.7.1.9b(3)")
Section
Figure 7.1.9b.(3).
The supply air duct is considered as part of the exit staircase, as such that part of the duct which traverses outside shall be protected.
As exit staircase is the means of escape, protecting it with masonry or equivalent would ensure the durability of the shaft during a fire situation.
As far as possible, the supply air duct should be located within the protected shaft, unless it is unavoidable.
(4) The ventilation system shall be of supply mode only, and of not less than 4 air changes per hour.
(5) The mechanical ventilation system shall be automatically activated by the building fire alarm system. In addition, a remote manual start-stop switch shall be made available to firefighters at the FCC, or, where there is no FCC, at the fire alarm panel.
(6) Visual indication of the operational status of the mechanical ventilation system shall be provided.
7.1.10 Ventilation system for smoke-free lobby and fire lift lobby
Effective Date: 1 Dec 2020
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Explanations & Illustrations
Clause 7.1.10 : Ventilation system for smoke-stop lobby
and fire lift lobby
Section
Figure 7.1.10 : Mechanical ventilation of smoke-stop/fire lift lobbies
The above figure shows that the supply air duct to the smoke-stop lobbies or fire fighting lobbies is provided with fire damper where it penetrates the compartment wall of the lobby. This is to ensure that the floor to floor compartmentation is maintained.
The portion of the duct which traverse outside the protected shaft is enclosed in fire rated construction e.g. fire-rated boards comply with Cl.3.8.9a. or Cl.3.8.7b.. The purposes of locating the manual start/stop switch with visual indication at the FCC, or at the main fire indicating board (FIB) where there is no FCC are:
(a) to allow firefighting personnel to shut down the supply air system temporarily in the event that smoke is being drawn into the lobby through the outdoor air intake; and
(b) to allow firefighting personnel to activate the supply air system should the fire alarm system fail to automatically activate the supply air system.
Amendment History
| 7.1.10 |
1 Dec 2020 |
1 Dec 2020 |
Clarification |
Ventilation system for smoke-free lobby and fire lift lobby a. The ventilation system shall be of supply mode only of not less than 10 air changes per hour. b. Supply air shall be drawn directly from the external space with intake point not less than 5m from any exhaust discharge or openings for natural ventilation. c. Any part of the supply duct running outside the smoke-free or fire lift lobby which it serves shall either be enclosed or constructed to give a 1-hr fire resistance rating. The SCDF may, at its discretion, require a higher fire resistance rating if the duct passes through an area of high fire risk. d. The mechanical ventilation system shall be automatically activated by the building fire alarm system. In addition, a remote manual start-stop switch shall be made available to firefighters at the FCC, or, where there is no FCC, at the main fire alarm panel. e. Visual indication of the operational status of the mechanical ventilation system shall be provided.
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1 Dec 2020 |
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a. The ventilation system shall be of supply mode only of not less than 10 air changes per hour.
b. Supply air shall be drawn directly from the external space with intake point not less than 5m from any exhaust discharge or openings for natural ventilation.
c. Any part of the supply duct running outside the smoke-free or fire lift lobby which it serves shall either be enclosed or constructed to give a 1-hr fire resistance rating. The SCDF may, at its discretion, require a higher fire resistance rating if the duct passes through an area of high fire risk.
d. The mechanical ventilation system shall be automatically activated by the building fire alarm system. In addition, a remote manual start-stop switch shall be made available to firefighters at the FCC, or, where there is no FCC, at the main fire alarm panel.
e. Visual indication of the operational status of the mechanical ventilation system shall be provided.
f. Where air conditioning is required for daily operations, this can be provided via supply and return air duct from the FCU/ AHU outside of the smoke-free/ fire lift lobby. Fire dampers shall be provided in the supply and return air ducts at penetrations through the compartment walls and/or floors. The ducts shall be fire-rated if it forms part of the other services passing through the smoke-free/ fire lift lobbies and/or the duct insulations are not of non-combustible type.
Amendment History
| 7.1.10 |
1 Dec 2020 |
1 Dec 2020 |
Clarification |
Ventilation system for smoke-free lobby and fire lift lobby a. The ventilation system shall be of supply mode only of not less than 10 air changes per hour. b. Supply air shall be drawn directly from the external space with intake point not less than 5m from any exhaust discharge or openings for natural ventilation. c. Any part of the supply duct running outside the smoke-free or fire lift lobby which it serves shall either be enclosed or constructed to give a 1-hr fire resistance rating. The SCDF may, at its discretion, require a higher fire resistance rating if the duct passes through an area of high fire risk. d. The mechanical ventilation system shall be automatically activated by the building fire alarm system. In addition, a remote manual start-stop switch shall be made available to firefighters at the FCC, or, where there is no FCC, at the main fire alarm panel. e. Visual indication of the operational status of the mechanical ventilation system shall be provided.
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1 Dec 2020 |
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7.1.11 Ventilation system for fire pump room and generator room
Effective Date: 2 Sep 2024
Where mechanical ventilation is installed to provide a smoke-free environment for the room housing the fire pump or emergency generator, such systems shall be independent of each other and of any other system serving other parts of the building, and shall comply with all of the following requirements:
Effective Date: 2 Sep 2024
Amendment History
| 7.1.11 |
2 Sep 2024 |
2 Sep 2024 |
Clarification |
7.1.11 Ventilation system for engine-driven fire pump room and generator room Where mechanical ventilation is installed to provide a smoke-free environment for the room housing the engine-driven fire pump or emergency generator, such systems shall be independent of each other and of any other system serving other parts of the building, and shall comply with all the following requirements: a. ………….
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2 Sep 2024 |
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a. Supply air shall be drawn directly from the external space and its intake point shall not be less than 5m from any exhaust discharge openings. Exhaust discharge shall also be direct to the external space.
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Explanations & Illustrations
Clause 7.1.11a. : Ventilation system for engine-driven
fire pump room and generator room
Section
Figure 7.1.11a.
The 5m clearance between supply and exhaust units refers to the horizontal distance. This is to prevent the recycling of exhaust air back into the building.
b. Where the corresponding ducts run outside the room they shall either be enclosed in a structure or be constructed to give at least the same fire rating as the room which they serve, or that of the room through which they traverse, whichever is higher.
The rating shall apply to fire exposure from both interior and exterior of the duct or structure. Where the duct risers are required to be enclosed in a protected shaft constructed of masonry or drywall complying with Cl.3.8.7b., they shall be compartmented from the rest of the shaft space containing other ducts or service installations.
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Explanations & Illustrations
Clause 7.1.11b. : Ventilation system for engine-driven
fire pump room and generator room
Section
Figure 7.1.11b.
The above figure shows that the ducts that run outside the protected shaft are enclosed in a structure or be constructed to give the necessary fire resistance rating. However, for the riser ducts which pass through one or more floors they are required to be enclosed in masonry shaft or drywall as required under Cl.3.8.9a.. This is to ensure that the riser ducts are properly protected within a shaft. The enclosure would ensure the integrity and stability of the riser ducts which pass floor to floor.
The provision of fire damper in the supply or exhaust duct is not allowed as the supply or exhaust system is required to function during emergency.
c. No fire damper shall be fitted in either supply or exhaust duct required under this clause.
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Explanations & Illustrations
Clause 7.1.11c. : Ventilation system for engine-driven
fire pump room and generator room
Section
Figure 7.1.11c. - 1
The concern is the stability of the riser ducts, if they pass through one or more floors
Figure 7.1.11c. - 2 : Protected shaft for ducts
As the mechanical ventilation system to generator room and fire pump room is independent of each other, the riser duct for each system shall be separately enclosed in a masonry or drywall shaft and compartmented from the rest of the shaft space containing other ducts or service installations.
Cl.3.8.9a. should also be referred to.
d. A duct serving areas other than rooms housing equipment stated in this clause shall not pass through such rooms.
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Explanations & Illustrations
Clause 7.1.11d. : Ventilation system for engine-driven
fire pump room and generator room
Figure 7.1.11d.
Ducts serving other areas shall not pass through the fire pump room, generator room and FCC. The above figure shows that the ventilation duct is diverted from traversing the equipment room.
7.1.12 Ventilation system for Fire Command Centre (FCC)
The FCC can either be air-conditioned, naturally ventilated or mechanically ventilated. The air-conditioning or mechanical ventilation shall be independent of each other and any other system serving other parts of the building. Where air-conditioning
or mechanical ventilation is provided, the fan coil unit or ventilation fan serving the FCC can be located within the FCC and shall also comply with all of the following requirements:
a. Supply air shall be drawn directly from the external space and its intake point shall not be less than 5m from any exhaust discharge openings. Exhaust discharge shall also be direct to the external space.
b. Where the corresponding ducts run outside the FCC, they shall either be enclosed in a structure or be constructed to give at least the same fire rating as the room which they serve or that of the room through which they traverse, whichever is higher.
Where the duct risers are required to be enclosed in a protected shaft constructed of masonry or drywall complying with Cl.3.8.7b.,
they shall be compartmented from the rest of the shaft space containing other ducts or service installations.
c. No fire damper shall be fitted in either supply or exhaust duct required under this Clause.
d. A duct serving areas other than the FCC shall not pass through the room.
7.1.13 Exhaust system for kitchen
a. Provision
A mechanical exhaust system for the cooking area of a kitchen in a hotel, restaurant, coffee house or the like shall be independent of those serving other parts of the building. It shall also comply with all of the following requirements:
(1) The hood and ducts for the exhaust shall have a clearance of 500mm from unprotected combustible materials.
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Explanations & Illustrations
Clause 7.1.13a.(1) : Exhaust system for kitchen
.tmb-firecode.png?Culture=en&sfvrsn=194e29_1 "Fg.7.1.13a(1)")
Section
Figure 7.1.13a.(1).
The hood and duct should be separated from other combustible materials by a minimum horizontal clearance of 500mm to prevent ignition through heat radiation. Class F portable fire extinguishers shall be provided according to SS 578.
(2) The exhaust shall discharge directly to the external space and shall not be less than 5m from any air intake openings.
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Explanations & Illustrations
Clause 7.1.13a.(2) : Exhaust system for kitchen
.tmb-firecode.png?Culture=en&sfvrsn=fec1a86c_1 "Fg.7.1.13a(2)")
Section
Figure 7.1.13a.(2).: Kitchen exhaust duct
(3) The exhaust duct, where it runs outside the kitchen, shall either be enclosed in a structure or be constructed to give at least the same fire rating as the kitchen or that of the room through which it traverses, whichever is higher. The rating shall
apply to fire exposure from both interior and exterior of the duct or structure. Where the duct riser is required to be enclosed in a protected shaft constructed of masonry or drywall complying with Cl.3.8.7b., it shall be compartmented from the rest of the shaft space containing other ducts or services installations.
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Explanations & Illustrations
Clause 7.1.13a.(3) : Exhaust system for kitchen
-1.tmb-firecode.png?Culture=en&sfvrsn=3826ddd6_1 "Fg.7.1.13a(3)-1")
Figure 7.1.13a.(3).- 1
Horizontal run of the exhaust duct outside the kitchen shall be fire-rated with minimum 1-hr fire resistance rating. The 1-hr fire resistance shall be applicable to the inside and outside of the
duct.
-2.tmb-firecode.png?Culture=en&sfvrsn=4028369e_1 "Fg.7.1.13a(3)-2")
Figure 7.1.13a.(3) - 2
The protecting structure for protected shaft containing kitchen exhaust duct that pass through one or more floors shall be of masonry construction or drywall.
To eliminate the risk of fire spreading from one compartment to another through burning grease within the duct system, a separate exhaust system is required for each hood located in separate compartments.
Fire dampers are not permitted within the duct system. The effectiveness of fire dampers is questionable as grease on the downstream side would likely ignite before the damper closed. The potential for false operation is also greater than normal and closure other than in a fire situation could have serious consequences. Further it is expected that the majority of kitchen hoods will have their own suppression thereby reducing the risk of fire spreading into the duct.
Continuation of the exhaust system during a fire involving the cooking equipment or in the compartment is not considered to aggravate the situation.
(4) No fire damper shall be fitted in kitchen exhaust ducts.
b. Sharing of kitchen exhaust system
Sharing of kitchen exhaust system for food and beverage outlets is allowed, provided all of the following conditions are complied with:
(1) For food courts
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Explanations & Illustrations
Clause 7.1.13b.(1) : Exhaust system for kitchen
.tmb-firecode.png?Culture=en&sfvrsn=76d0c2cf_1 "Fg.7.1.13b(1)")
NRD = Non-rated duct
Figure 7.1.13b.(1)
To share a kitchen exhaust system within a food court, it needs to be under a single ownership/operator. In addition, it is also required to make provision for maintenance and cleaning of the exhaust system, i.e. degreased & cleaned regularly.
All kitchen exhaust ducts running outside the food court shall have minimum 1-hr fire resistance rating or not less than that for the elements of structure, whichever is higher.
(a) The food court shall be under a single ownership/ operator.
(b) All kitchen exhaust ducts running outside the food court shall have 1-hr fire resistance rating, or shall not be less than that for the elements of structure, whichever is higher.
(2) For restaurants/small F&B outlets (e.g. snack bars, food kiosks, etc.)
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Explanations & Illustrations
Clause 7.1.13b.(2) : Exhaust system for kitchen
-1.tmb-firecode.png?Culture=en&sfvrsn=9438b224_1 "Fg.7.1.13b(2)-1")
Figure 7.1.13b.(2)
To be precise, each restaurant shall be provided with its own kitchen exhaust duct. Where the restaurants are located close to each other, on the same floor, within a zone of not more than 2000m2 and have aggregate floor area of not more than 1000m², the sharing of kitchen exhaust duct is permitted.
Where the restaurants are located far from each other, then the relaxation of common kitchen exhaust duct shall not be applicable. In other words, each restaurant unit shall have its own kitchen exhaust duct.
(a) Restaurants and small F&B outlets that are sharing the same kitchen exhaust system shall be located on the same storey and within the aggregate zone area not exceeding 2000m2. The maximum length of the aggregate zone covering from the first to the last restaurant/F&B outlet shall not exceed 50m.
(b) The aggregate floor area of the restaurants and F&B outlets shall not exceed 1000m2.
Effective Date: 01 Mar 2019
Amendment History
| 7.1.13b.(2)(a) and (b) |
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01 Mar 2019 |
Revised, formerly Cl.7.1.7(b)(ii) |
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(c) Common ducts shall be provided with a common exhaust fan.
(d) The building shall be protected by an automatic fire sprinkler system.
(e) The exhaust hood shall be fitted with a wet chemical fire extinguishing system.
(f) The fire rating of the common kitchen exhaust duct running outside the restaurants shall have 1-hr fire resistance rating, or shall not be less than that for the elements of structure, whichever is higher.
(Note: Kitchen exhaust ducts include both horizontal and vertical ducts.)
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Note to QPs on Clause
Wet chemical fire extinguishing systems for exhaust hood(s) shall be of approved type based on international standards such as NFPA 17A. QPs are also reminded to ensure that the premise owners/ operators are aware of the stipulated maintenance regime in the standards.
c. Kitchen exhaust duct (KED)
(1) A KED running outside a building shall not be located within 3m of any unprotected openings. This separation distance can be reduced to 1.5m if the unprotected opening is on the same plane as the duct. (See Diagram 7.1.13c.(1) - 1 and
2)
(2) Where the distances mentioned above cannot be achieved, a fire resistant construction having at least ½-hr fire resistance shall be placed between the duct and the unprotected opening. (See Diagram 7.1.13c.(2))
(3) A non-fire-rated KED shall not be located above an LPG storage cabinet, unless they are separated from LPG cylinders by a minimum of 2-hr fire-rated masonry construction above and beside the cylinders. (See Diagram 7.1.13c.(3))
(4) The KED shall be located at least 3m from any unprotected LPG cylinders. Non-fire-rated KED shall be located at least 600mm from the vapouriser or any liquid-phase LPG pipeline. (See Diagram 7.1.13c.(4))
(5) Access panels for KED
KED shall be provided with openings via access panels to facilitate inspection and maintenance, which shall comply with the following:
Effective Date: 1 Mar 2023
Amendment History
| 7.1.13c. |
1 Mar 2023 |
1 Mar 2023 |
Revised/Clarifications |
Kitchen exhaust duct
(1) A kitchen exhaust duct running outside a building shall not be located within 3m of any unprotected openings. This separation distance can be reduced to 1.5m if the unprotected opening is on the same plane as the duct. (See Diagram 7.1.13c.(1) - 1 and 2)
(2) Where the distances mentioned above cannot be achieved, a fire resistant construction having at least ½-hr fire resistance shall be placed between the duct and the unprotected opening. (See Diagram 7.1.13c.(2))
(3) A non-fire-rated kitchen exhaust duct shall not be located above an LPG storage cabinet, unless they are separated from LPG cylinders by a minimum of 2-hr fire-rated masonry construction above and beside the cylinders. (See Diagram 7.1.13c.(3))
(4) The kitchen exhaust duct shall be located at least 3m from any unprotected LPG cylinders. Non-fire-rated kitchen exhaust duct shall be located at least 600mm from the vapouriser or any liquid-phase LPG pipeline. (See Diagram 7.1.13c.(4))
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1 Sep 2022 |
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| 7.1.13c. and d. |
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1 Dec 2014 |
Extracted from SCDF's circular |
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29 May 2014 |
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| 7.1.13d. |
1 Mar 2023 |
1 Mar 2023 |
Revised/Clarifications |
Maintenance
All kitchen exhaust systems shall be properly maintained. The entire (interior and exterior) exhaust duct and kitchen hood shall be degreased and cleaned at least once every 12 months. The work shall be carried out by a specialist and the records of cleaning and degreasing shall be kept by the owner/operator for verification by the authority having jurisdiction. This requirement shall be included in the Fire Safety Instruction Manual.
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1 Sep 2022 |
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(a) Access panels shall be provided to allow the interior of the duct to be viewed without the assistance of tools, to facilitate thorough cleaning. The access panels shall not be obstructed by suspended ceilings, cable routes, pipes or other installations.
Effective Date: 1 Mar 2023
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Amendment History
| 7.1.13c. |
1 Mar 2023 |
1 Mar 2023 |
Revised/Clarifications |
Kitchen exhaust duct
(1) A kitchen exhaust duct running outside a building shall not be located within 3m of any unprotected openings. This separation distance can be reduced to 1.5m if the unprotected opening is on the same plane as the duct. (See Diagram 7.1.13c.(1) - 1 and 2)
(2) Where the distances mentioned above cannot be achieved, a fire resistant construction having at least ½-hr fire resistance shall be placed between the duct and the unprotected opening. (See Diagram 7.1.13c.(2))
(3) A non-fire-rated kitchen exhaust duct shall not be located above an LPG storage cabinet, unless they are separated from LPG cylinders by a minimum of 2-hr fire-rated masonry construction above and beside the cylinders. (See Diagram 7.1.13c.(3))
(4) The kitchen exhaust duct shall be located at least 3m from any unprotected LPG cylinders. Non-fire-rated kitchen exhaust duct shall be located at least 600mm from the vapouriser or any liquid-phase LPG pipeline. (See Diagram 7.1.13c.(4))
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1 Sep 2022 |
Download
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| 7.1.13c. and d. |
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1 Dec 2014 |
Extracted from SCDF's circular |
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29 May 2014 |
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| 7.1.13d. |
1 Mar 2023 |
1 Mar 2023 |
Revised/Clarifications |
Maintenance
All kitchen exhaust systems shall be properly maintained. The entire (interior and exterior) exhaust duct and kitchen hood shall be degreased and cleaned at least once every 12 months. The work shall be carried out by a specialist and the records of cleaning and degreasing shall be kept by the owner/operator for verification by the authority having jurisdiction. This requirement shall be included in the Fire Safety Instruction Manual.
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1 Sep 2022 |
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(b) Access panels shall be located at the sides of the duct.
Effective Date: 1 Mar 2023
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Amendment History
| 7.1.13c. |
1 Mar 2023 |
1 Mar 2023 |
Revised/Clarifications |
Kitchen exhaust duct
(1) A kitchen exhaust duct running outside a building shall not be located within 3m of any unprotected openings. This separation distance can be reduced to 1.5m if the unprotected opening is on the same plane as the duct. (See Diagram 7.1.13c.(1) - 1 and 2)
(2) Where the distances mentioned above cannot be achieved, a fire resistant construction having at least ½-hr fire resistance shall be placed between the duct and the unprotected opening. (See Diagram 7.1.13c.(2))
(3) A non-fire-rated kitchen exhaust duct shall not be located above an LPG storage cabinet, unless they are separated from LPG cylinders by a minimum of 2-hr fire-rated masonry construction above and beside the cylinders. (See Diagram 7.1.13c.(3))
(4) The kitchen exhaust duct shall be located at least 3m from any unprotected LPG cylinders. Non-fire-rated kitchen exhaust duct shall be located at least 600mm from the vapouriser or any liquid-phase LPG pipeline. (See Diagram 7.1.13c.(4))
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1 Sep 2022 |
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| 7.1.13c. and d. |
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1 Dec 2014 |
Extracted from SCDF's circular |
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29 May 2014 |
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| 7.1.13d. |
1 Mar 2023 |
1 Mar 2023 |
Revised/Clarifications |
Maintenance
All kitchen exhaust systems shall be properly maintained. The entire (interior and exterior) exhaust duct and kitchen hood shall be degreased and cleaned at least once every 12 months. The work shall be carried out by a specialist and the records of cleaning and degreasing shall be kept by the owner/operator for verification by the authority having jurisdiction. This requirement shall be included in the Fire Safety Instruction Manual.
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1 Sep 2022 |
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(c) Access panels are not required at the duct entry, duct discharge, or sections of the duct which are fire-rated or protected with fire-rated enclosure. Excluding these exempted areas, access panels shall be provided at the following locations:
(i) at changes of ducting direction;
(ii) if fire extinguishing systems are provided, to facilitate installation and servicing of the fire extinguishing systems;
(iii) within 900mm of each side of exhaust fan assemblies;
(iv) at least 40mm from all outside edges of the duct or welded seams; and
(v) in addition to compliance with subclause (i) to (iv), access panels shall be located at maximum 3m intervals for horizontal ducting, and at the top and bottom of sections of vertical ducting which runs solely at the building exterior.
(d) Access panels shall be conspicuously marked with the following wording: ACCESS PANEL – DO NOT OBSTRUCT. The lettering shall be at least 25mm in height, in a colour contrasting with the background.
Effective Date: 1 Mar 2023
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Amendment History
| 7.1.13c. |
1 Mar 2023 |
1 Mar 2023 |
Revised/Clarifications |
Kitchen exhaust duct
(1) A kitchen exhaust duct running outside a building shall not be located within 3m of any unprotected openings. This separation distance can be reduced to 1.5m if the unprotected opening is on the same plane as the duct. (See Diagram 7.1.13c.(1) - 1 and 2)
(2) Where the distances mentioned above cannot be achieved, a fire resistant construction having at least ½-hr fire resistance shall be placed between the duct and the unprotected opening. (See Diagram 7.1.13c.(2))
(3) A non-fire-rated kitchen exhaust duct shall not be located above an LPG storage cabinet, unless they are separated from LPG cylinders by a minimum of 2-hr fire-rated masonry construction above and beside the cylinders. (See Diagram 7.1.13c.(3))
(4) The kitchen exhaust duct shall be located at least 3m from any unprotected LPG cylinders. Non-fire-rated kitchen exhaust duct shall be located at least 600mm from the vapouriser or any liquid-phase LPG pipeline. (See Diagram 7.1.13c.(4))
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1 Sep 2022 |
Download
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| 7.1.13c. and d. |
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1 Dec 2014 |
Extracted from SCDF's circular |
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29 May 2014 |
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| 7.1.13d. |
1 Mar 2023 |
1 Mar 2023 |
Revised/Clarifications |
Maintenance
All kitchen exhaust systems shall be properly maintained. The entire (interior and exterior) exhaust duct and kitchen hood shall be degreased and cleaned at least once every 12 months. The work shall be carried out by a specialist and the records of cleaning and degreasing shall be kept by the owner/operator for verification by the authority having jurisdiction. This requirement shall be included in the Fire Safety Instruction Manual.
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1 Sep 2022 |
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d. Maintenance
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Note to QPs on Clause 7.1.13d
Building owners, MCSTs and eating outlet operators shall ensure that the entire (interior and exterior) kitchen exhaust duct and kitchen hood shall be degreased and cleaned at least once every 12 months. The work shall be carried out by a specialist and the records of cleaning and degreasing shall be kept by the owner/MCST/operator for verification by the authority having jurisdiction.
All kitchen exhaust systems shall be properly maintained in accordance with the following:
(1) The entire (interior and exterior) exhaust duct and kitchen hood shall be degreased and cleaned at least once every 12 months.
(2) The work shall be carried out by a specialist and the records of cleaning and degreasing shall be kept by the owner/ operator for verification. This requirement shall be included in the Fire Safety Instruction Manual.
7.1.14 Ventilation system for rooms involving use of flammable and explosive substances
a. Dedicated system
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Explanations & Illustrations
Clause 7.1.14a. : Ventilation system for engine-driven
fire pump room and generator room
Section
Figure 7.1.14a. - 1
The exhaust system (without fire damper) is required to operate efficiently to remove any gaseous or flammable vapour from the room.
a. Where the flammable vapour being removed is heavier than air:
(1) At least one air outlet shall be located at a point near a wall, and no higher than 300mm from the floor; and
(2) At least one air inlet shall be located near the opposite wall, no lower than 300mm from the ceiling.
b. Where the flammable vapour being removed is lighter than air:
(1) At least one air inlet shall be located at a point near a wall, and no higher than 300mm from the floor; and
(2) At least one air outlet shall be located near the opposite wall, no lower than 300mm from the ceiling.
Figure 7.1.14a. - 2
The flammable vapour which is heavier than the air will be discharged via the exhaust system (without damper) as shown above. Do refer to relevant SS for full compliance.
Mechanical ventilation systems, where required for rooms which involve the use of flammable and explosive substances, shall be independent from those serving other parts of the building. They shall comply with all of the following requirements:
(1) Ventilation system shall consist of exhaust and supply parts with a rate of 20 air changes per hour or any other rates acceptable to the SCDF. The exhaust shall direct to the external space and shall not be less than 5m from any air intake openings.
(2) Where such ducts run outside the room they shall either be enclosed in a structure or be constructed to give at least the same fire rating as the room which they serve or that of the room through which they traverse, whichever is higher. The rating
shall apply to fire exposure from both interior and exterior of the duct or structure. Where the duct risers are required to be enclosed in a protected shaft constructed of masonry or drywall complying with Cl.3.8.7b., they shall be compartmented from the rest of the shaft space containing other ducts or service installations.
(3) No fire damper shall be fitted in either a supply or exhaust duct required under this Clause.
(4) Ducts serving other areas shall not pass through rooms involving use of flammable and explosive substances.
b. Sharing of supply air duct
A common fire-rated supply air duct can serve various compartments within the same floor level or other floor levels, provided:
(1) the compartments are sprinkler-protected;
(2) the compartments are of the same purpose group;
(3) the duct is fitted with a fire damper where it passes through the wall or floor of each fire compartment; and
(4) a dedicated exhaust duct is provided for individual fire compartments and shall be maintained in operation (with the minimum flow rate) even it is under fire mode situation to prevent smoke entering into other fire compartments.
Effective Date: 01 Mar 2019
Amendment History
| 7.1.14b |
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01 Mar 2019 |
Revised, formerly Cl.7.1.8(a) |
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7.1.15 Ventilation system for rooms housing batteries
Effective Date: 01 Mar 2019
Amendment History
| 7.1.15 |
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01 Mar 2019 |
New |
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Rooms housing batteries shall comply with the following requirements:
a. The batteries shall be of either vented or sealed type.
b. The room ventilation system shall be designed to limit the maximum concentration of Hydrogen (H2) gas to 1% of the total volume of the room during the worst case event of simultaneous “boost” charging of the batteries. The inlets and outlets of the ventilation system shall be properly located so that there is no stagnant area in the room.
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Rationale - Clause 7.1.15b
The revision is in line with NFPA to limit the maximum concentration of hydrogen to 1% of the total volume of the room. The ventilation rate for the room shall be computed in accordance with BS EN IEC 62485 or 6 air changes, whichever is higher.
c. Adequate hydrogen gas detectors shall be provided inside the room to monitor the hydrogen concentration and to activate the fan, if necessary, to ensure that the hydrogen concentration level at any part of the room does not exceed 1% of the total volume
of the room. Display panels showing the readings of the detectors shall be located at the entrance to the room. At the same time, an alarm signal shall be sent to a manned station such as security control room, guard house or FCC.
d. The design of the battery room ventilation shall be in accordance with BS EN IEC 62485-2 & BS EN IEC 62485-3.
e. For mechanically ventilated battery rooms, the ventilation requirement shall be based on Cl.7.1.15d.,
or 6 air changes per hour, whichever is higher.
f. No fire damper shall be provided in the essential ventilation system and ducts passing through other compartments shall have 2-hr fire resistance rating.
g. Essential fans and associated electrical controls shall be backed up with a secondary source of power supply.
-new.png?sfvrsn=3794c956_4&MaxWidth=500&MaxHeight=394&ScaleUp=false&Quality=High&Method=ResizeFitToAreaArguments&Signature=7E424311AC09636F8F4BFC2B4F7495F8CEB4DF54 "Fig 7.1.13c.(5) New")
-new.png?sfvrsn=38ec77ff_4&MaxWidth=500&MaxHeight=394&ScaleUp=false&Quality=High&Method=ResizeFitToAreaArguments&Signature=0778C609984AEC60BDAE6F34F367E7BA665E8C8F "Fig 7.1.13c.(6) New")
-new.png?sfvrsn=78db3865_4&MaxWidth=500&MaxHeight=394&ScaleUp=false&Quality=High&Method=ResizeFitToAreaArguments&Signature=8B8E52BE3296C54792CD323FB34ED46042A5D496 "Fig 7.1.13c.(7) New")
-new.png?sfvrsn=5294af75_4&MaxWidth=500&MaxHeight=394&ScaleUp=false&Quality=High&Method=ResizeFitToAreaArguments&Signature=7A6746B7B945E054F6FE679A2B5D031A5E579C3E "Fig 7.1.13c.(8) New")
-new.png?sfvrsn=8d45931f_4&MaxWidth=500&MaxHeight=394&ScaleUp=false&Quality=High&Method=ResizeFitToAreaArguments&Signature=11ABA713EB05822A988E068779CA812F39DF4CE5 "Fig 7.1.13c.(9) New")