Clause 2.2 Determinations of Exit Requirements

Clause 2.2 - DETERMINATION OF EXIT REQUIREMENTS

2.2.1 General

R Rationale - Clause 2.2.1

The exit provisions allow occupants to leave the fire area safely in the shortest possible time to a safe area.

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The determination of exit requirements for a building shall be based upon the type of use or occupancy of the building, the occupant load, the floor area, the travel distance to an exit and the capacity of exits as provided in Table 2.2A and herein. Every storey of a building shall be provided with exit facilities for its occupant load. Vertical exits provided from any storey above ground level may serve simultaneously all storeys above the ground level. Vertical exits provided from any storey below ground level may serve all storeys below ground level, subject to the provisions of Cl.2.3.5 which prohibit basement staircases being continuous with exit staircases serving the upper storeys, unless otherwise allowed by the SCDF.

2.2.2 Mixed occupancy

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Explanations & Illustrations

Clause 2.2.2 : Mixed occupancy

MIXED OCCUPANCY - OFFICES, FACTORIES & WAREHOUSES

1. TRAVEL DISTANCE REQUIREMENT:-

For a storey of mixed occupancy building consisting of offices, factories and warehouses, the exit capacity of staircases may be based on the total of the occupancies computed separately for each usage type as per Table 1.4B. However the position of the exit staircases shall be so located that the maximum permissible travel distance from any remote point to the staircase shall be based on that of the factory, having the stricter requirements in Table 2.2A. That is, equal to 30m for two-way non-sprinkler-protected buildings and 60m for two-way sprinkler protected buildings, and not the 45m and 75m distances allowable for office developments. Hence:

Travel distance (in Figure 2.2.2-1) to the nearest exit staircase shall not exceed 30m or 60m (if sprinkler-protected).

The Direct distance to the nearest exit staircase, if there are no predetermined walls, shall not exceed 20m (2/3 x 30m) or 40m (2/3 x 60m, if sprinkler-protected).

Fg.2.2.2-1

Figure 2.2.2 - 1 : Example of a mixed development with factory, office & storage

The exit provisions in a mixed development may be assessed and provided separately if the differing purpose types are clearly defined and compartmentalized. For example, the escape distances for the offices’ area which is clearly located in one part of the building as shown in Figure 2.2.2 – 2, may be based on the office configurations given in Table 2.2A. The remaining part of the building with the industrial usage is then based on the factory configurations.

Fg.2.2.2-2

Figure 2.2.2 - 2 : Example of separate travel distance application

2. EXIT REQUIREMENT:-

Buildings with mixed occupancies the exit capacity of its exit staircases shall be based on the type of occupancy or usage having the strictest exit requirements given in Table 2.2A.

For example;

A storey of a building comprises dormitory, production and offices separated by usage with compartment walls, but shares common facilities like the staircases.

Then the exit capacity of its staircases shall be based on:

Dormitory occupancy which the number of persons per unit of exit width (500mm) of staircase is 45 persons.

Instead of:

Factory / Office / Warehouse occupancies which the number of persons per unit of exit width (500mm) of staircase is 60 persons.

Fg.2.2.2-3

Figure 2.2.2 - 3 : Mixed factory development with office & dormitory blocks sharing common exit staircases

The maximum permissible occupant load (OL) for the entire storey of the building in Figure 2.2.2 - 3, for example, shall be based on the capacity of the two exit staircases of 2m width each, assumed serving a dormitory building. i.e.

OL = 4 units x 45 persons x 2 staircases
= 360 persons (maximum per storey)

Fg.2.2.2-4

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Figure 2.2.2 - 4 : Building with mixed occupancy

Fg.2.2.2-5

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Figure 2.2.2 - 5 : Building with mixed occupancy

This capacity of staircase exit width shall be applicable for all levels or storeys of the building with such shared staircase arrangement. This is regardless of the dormitory being located on the second storey or the top most storey of a multi-storey building. The only exemption is when the space with the more stringent requirement per unit of exit width, e.g. the dormitory, is located on only the ground level storey with direct escape to the external space.

(1) Travel distance requirement:

For a storey of mixed occupancy building consisting of offices, shops and place of public resort, the exit capacity of staircases may be based on the total of the occupancies computed separately for each usage type as per Table 1.4B. However the position of the exit staircases shall be so located that the maximum permissible travel distance from any remote point to the staircase shall be based on that of the shop, having the stricter requirements in Table 2.2A . That is, maximum 45m two-way escape travel distance for non-sprinkler-protected buildings and 60m two-way escape travel distance for sprinkler protected buildings shall be applicable and not the 45m and 75m distances allowable for office developments. Hence:

Travel distance (in Figure 2.2.2 - 1) to the nearest exit staircase shall not exceed 30m or 60m (if sprinkler-protected).

The direct distance to the nearest exit staircase, if there are no predetermined walls, shall not exceed 30m (2/3 x 45m) or 40m (2/3 x 60m, if sprinkler-protected).

MIXED OCCUPANCY - OFFICES, SHOPS & PLACES OF PUBLIC RESORT

1. TRAVEL DISTANCE REQUIREMENT:

For a storey of mixed occupancy building consisting of offices, shops and place of public resort, the exit capacity of staircases may be based on the total of the occupancies computed separately for each usage type as per Table 1.4B. However the position of the exit staircases shall be so located that the maximum permissible travel distance from any remote point to the staircase shall be based on that of the shop, having the stricter requirements in Table 2.2A. That is, maximum 45m two-way escape travel distance for non-sprinkler-protected buildings and 60m two-way escape travel distance for sprinkler-protected buildings shall be applicable and not the 45m and 75m distances allowable for office developments. Hence:

Travel distance (in Diagram 2.2.2-1) to the nearest exit staircase shall not exceed 30m or 60m (if sprinkler-protected).

The direct distance to the nearest exit staircase, if there are no predetermined walls, shall not exceed 30m (2/3 x 45m) or 40m (2/3 x 60m, if sprinkler-protected).

Fg.2.2.2-6

Figure 2.2.2 - 6

The exit provisions in a mixed development may be assessed and provided separately if the differing purpose types are clearly defined and compartmentalised.

For example, the escape distances for the offices’ area, which is clearly located in one part of the building as shown in Figure 2.2.2 - 6, may be based on the office configurations given in Table 2.2A. The remaining part of the building with the shopping usage is then based on the shop configurations.

Fg.2.2.2-7

Figure 2.2.2 - 7 Example of separate travel distance application

Fg.2.2.2-8

Figure 2.2.2 - 8

2. EXIT REQUIREMENT:

Buildings with mixed occupancies the exit capacity of its exit staircases shall be based on the type of occupancy or usage having the strictest exit requirements given in Table 2.2A.

For example, see Figure 2.2.2 - 3

A storey of a building comprises office and hotel residential occupancy separated by compartment walls, but shares common facilities like the staircases and lifts.

Then the exit capacity of its shared staircase (staircase S2) shall be based on the most stringent type of mixed occupancies, i.e. hotel residential floors.

Office Occupancy (Staircase S1)
No. of persons per unit of exit width (500mm) of staircase = 60 persons.

Hotel Residential Occupancy (Staircase S2 & S3)
No. of persons per unit of exit width (500mm) of staircase = 45 persons.

Fg.2.2.2-9

Figure 2.2.2 - 9 : Mixed development with office, shop & restaurant sharing common exit staircases

In the case of restaurant, the maximum permissible occupant load can be based on the capacity of the three staircases. As Staircase S3 is for the exclusive use of restaurant, owing to its location, this staircase is inaccessible to occupants from offices and shops. Therefore, Staircase S3 shall not be computed as a common exit staircase rather computed as exit staircase for restaurant only. That is:

Exit capacity of common staircases = 4 units x 60 persons x 2 staircases

(Staircases S1 & S2 of 2m width each) = 480 persons

Hence, each common exit staircase can accommodate 240 persons (½ of 480 persons)

It is acceptable to allow ½ the occupant load of restaurant to use Staircase S3 and the other ½ to use the common exit staircases S1 & S2. Therefore, the maximum permissible occupant load for shops and offices shall include ½ the occupant load of restaurant, subject to not exceeding a total of 480 persons.

Fg.2.2.2-10

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Figure 2.2.2 - 10 : Situation where the exit capacities of entire staircase on all storeys are accounted similarly

The strictest capacity of staircase exit width (applicable to restaurant) shall be applicable to all levels or storeys of the building with such shared staircase arrangement. This is regardless of the restaurant being located on the second storey or the top most storey of a multi-storey building.

Fg.2.2.2-11

Figure 2.2.2 - 11 : Mixed occupancy building

Auditorium space shares the internal corridor as the classrooms. Such space cannot be qualified as non-simultaneous occupancy within the same storey.

Where different parts of a building or storey of a building are designed for different types of occupancies or used for different purposes at the same time, the exit requirements of the entire building or storey of the building shall be determined on the basis of that type of occupancy or usage having the strictest exit requirements or the exit requirements for each building section shall be determined separately.

2.2.3 Multiple occupancy or use

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Where a building or storey of a building or a part of a building is used for multiple purposes involving different activities at different times, that purpose or use involving the greatest number of occupants shall form the basis for determining the exit requirements.

2.2.4 Non-simultaneous occupancy

Effective Date: 25 Aug 2023

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Clause No.	Amendment Date	Effective Date	Clause Status	Clause Before Amendment	Circular Date	Download Circular
2.2.4	25 Aug 2023	25 Aug 2023	Revised/Clarification	2.2.4 Non-simultaneous occupancy The floor areas of toilets, locker rooms, storage rooms, lobbies, corridors and similar rooms and spaces that serve other rooms and spaces on the same storey but are not occupied at the same time as such other rooms or spaces, can be omitted from the occupant load calculations of that storey of the building on which they are located.	25 Aug 2023	Download

The floor areas of toilets, locker rooms, lobbies, and corridors that are not occupied at the same time as other rooms or spaces by building occupants, can be omitted from the occupant load calculations of that storey of the building in which the storey is located.

2.2.5 Capacity of exits and exit facilities

R Rationale - Clause 2.2.5

Adhering to the design parameters will prevent overcrowding and will ensure the corridors, exit staircases and doors are adequate in size to receive all the occupants on that floor during evacuation.

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Explanations & Illustrations

Clause 2.2.5 : Capacity of exits & exit facilities

To prevent overcrowding one has to ensure that the corridor and the exit staircases serving a storey of a building are adequate in size to receive all the occupants on that floor at the time of evacuation.

Fg.2.2.5-1

Figure 2.2.5 - 1 : Typical floor plan of standard slab design

The capacity of exit doors to the industrial units, corridor, exit doors to staircases and exit staircases are measured in units of width of one half of a metre i.e.:

Exit door/corridor/staircase clear width	Number of unit width
1m	2
1.5m	3
2m	4

Where a fraction of 250mm or more are added to one or more full units, half of a unit of width shall be credited, for example:

Exit door/corridor/staircase clear width	Number of unit width
1000 to 1249mm	2
1250 to 1499mm	2.5
1500 to 1749mm	3
1750 to 1999mm	3.5
2000mm (maximum)	4 (maximum number per exit)

The number of persons per unit of width shall be determined by the type of occupancy and type of exit as listed under Table 2.2A of the current Fire Code.

Example 1 : High hazard building

1 unit width = 500mm = 30 and 40 persons per unit width through staircase and doorway respectively.

Therefore: 1m doorway facilitates escape for 80 occupants from a high hazard factory, while 1m of its stairway permits escape for only 60 of its occupants.

The high hazard building has very much more stringent requirements than other buildings. It is due to the nature of its contents. In an emergency situation, because of the highly volatile or explosive nature of the contents, its occupants have very little reaction time to evacuate to a safer area. Hence, exits must be designed such that they are more readily available for escape purposes.

Where a room or space is required to be provided with two exits, each exit shall be of sufficient width to accommodate not less than one half the total occupant load.

Fg.2.2.5-2

Figure 2.2.5 - 2 : Acceptable distribution of exit capacity

Fg.2.2.5-3

Figure 2.2.5 - 3 : Not Acceptable distribution of exit capacity

The above sub-clause is to address the problem, which may arise if staircases are not proportionately sized and distributed. For example, a fire near Stair A in Diagram 2.2.5 –3, which is designed to facilitate escape for 240 persons, can render it inaccessible. This would mean that, the other exit, stair B, which is only designed for 120 persons’ escape, would hence need to facilitate escape for the full OL of 360 persons from that storey.

This scenario would render stair B to be drastically inadequate to facilitate all the occupants’ timely escape, before the fire and smoke engulf the entire floor space. This is because it would require three times as long to evacuate the occupants from that storey using only stair B.

Imagine the consequences, for a scenario where the entire staircase A with the larger exit capacity is totally damaged or not usable in a high-rise building fire.

a. The capacity of exits, exit staircases, exit passageways, corridors, exit doors and other exit facilities shall be measured in units of half a metre's width. The number of persons per unit of width shall be determined by the type of occupancy and type of exit as listed under Table 2.2A. In the determination of each exit width, fractions of a unit width less than 250mm shall not be factored in the measurement. Where 250mm or more are added to one or more full units, half of a unit of width shall be factored in.

b. Where a room or space is required to be provided with two exits, each exit shall be of sufficient width to accommodate not less than half the total occupant load.

2.2.6 Determination of travel distance

The maximum travel distance for the respective types of occupancies shall be not greater than as laid down in Table 2.2A and read in conjunction with all of the following:

a. In the case of a floor area designed with minimum two exits, the maximum travel distance as given in Table 2.2A shall be applicable. The maximum travel distance starting from the most remote point in any occupied space to the nearest exit, shall not exceed the limits specified in Table 2.2A.

R Rationale - Clause 2.2.6a

The travel distance serves to limit the distance a person is required to travel from the occupied space to an exit staircase door, which every designer should observe. On the other hands, it must also be stated that conforming to the permissible travel distance alone does not necessarily guarantee building occupant life safety during an emergency.

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b. In a large floor area without sub-division of rooms, corridors and so forth, the travel distance can adopt the “direct distance” concept as a guide and shall not exceed two-third of the maximum travel distance permitted under Table 2.2A. Where the large floor area is undergoing sub-division of rooms, corridors, etc., the maximum travel distance shall be in accordance with Table 2.2A.

R Rationale - Clause 2.2.6b

The two-third direct distance method is intended to guide designer for planning of large open floor layout for facilitating flexibility for future inclusions and changes in layout. This guide serves to minimise problem of complying with travel distance during subsequent A/A works.

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Explanations & Illustrations

Clause 2.2.6b. :Determination of travel distance

Similarly, if the details of the internal layout are furnished on the building plan submissions, hence the actual travel distances permissible under the Table 2.2A would be taken into account.

However, in most situations during the planning and building plan submission stages of a building, its designer is unable to confirm the layout of the storey spaces. It is therefore recommended that the direct distance measurements, which are two thirds of the allowable travel distances, be strictly applied to such ‘open’ plans.

Example

Fg.2.2.6b-1

Figure 2.2.6b. - 1 : Typical single tenancy single office storey

The dotted walls in Figure 2.2.6(b) - 1, for example, may not be shown on plan and/or may be of differing configurations. In such indefinite situation, a straight line drawn from the most remote point A to B or C shall be taken as the two-way direct distance. If the maximum permissible two-way travel distance given in Table 2.2A for such usage is 60m (sprinkler-protected), then the direct distances (straight lines AB or AC) shall not exceed 40m, i.e. ⅔ x 60m. This shall also apply to the one-way distances BD and CF, as the actual one-way distances could possibly be D1HB and F1JC.

This application of the direct distance measurements, besides facilitating flexibility for future inclusions and changes in layout, ensures that escape distances for the occupants would not subsequently be excessive and life threatening in a fire emergency.

(Note: “travel distance” is to be taken as direct distance).

Maximum escape distance design parameters

Item	Sprinklered			Non-sprinklered
Item	Shops	Offices	Places of public resort	Shops	Offices	Places of public resort
1-way Travel Distance (m)	25	30	25	15	15	15
1-way Direct Distance (m)	16.6	20	16.6	10	10	10
2-way Travel Distance (m)	60	75	60	45	45	45
2-way Direct Distance (m)	40	50	40	30	30	30

Fg.2.2.6b-2

Figure 2.2.6b. - 2 : Typical storey plan of an office building

DIRECT DISTANCE = ⅔ TRAVEL DISTANCE

The actual path that an occupant needs to take from any part of a storey space to the nearest exit door to the external space or exit staircase, will be measured for escape travel distance compliance. This distance takes into account the internal partitions within that floor space and it shall comply with the relevant travel distances stipulated in Table 2.2A.

Thus, where details of the internal layout are furnished in the building plan submissions, for example Figure 2.2.6 (a) & (b) – 1, the full travel distances permissible under the Table 2.2A would be applied.

However, in most situations during the planning and building plan submission stages of a building, the designer is unable to confirm the internal layout of the storey spaces. It is recommended that the direct distance measurement, which is two thirds of the allowable travel distances, should be applied to such ‘open’ layout plans.

Example

Fg.2.2.6b-3

Figure 2.2.6b. - 3

Fg.2.2.6b-4

Figure 2.2.6b. - 4

A to B is considered as one-way travel distance and it shall be not more than 25m (sprinkler-protected). In computing two-way travel distance, the escape route from point A, B, C shall not exceed 60m (sprinkler-protected)

Fg.2.2.6b-5

Figure 2.2.6b. - 5

Point A to C and Point A to B are considered two-way travel distance if the separation distance between exit doors of the two staircases is equal to or more than ½D or ⅓D (sprinkler-protected). If the storey space is to be subdivided for occupation by more than one occupier, a common corridor around the service core shall be created to meet the travel distance requirements.

Fg.2.2.6b-6

Figure 2.2.6b. - 6

Escape routes AB, AC are considered two-way direct travel. Escape routes DE, FG are considered one-way direct travel distances.

Fg.2.2.6b-7

Figure 2.2.6b. - 7

The numerous one-way direct travel distances are illustrated by dashed lines.

The provision of fixed corridors and rooms in an open floor space would create numerous “common paths” from the rooms to the exit staircases as shown in the above figure. Common paths of travel are one-direction travel only without the choice of travelling in another separate direction toward an exit.

Fg.2.2.6b-8

Figure 2.2.6b. - 8

In determining the types of travel distance, Point A, B or C is considered one-way travel distance or “common path”. At point C, where an occupant has the choice of more than one escape direction, would be considered as the starting point for 2-way travel distance. Hence, escape routes C E and C D are considered two-way travel distance.

Fg.2.2.6b-9

Figure 2.2.6b. - 9 : Example of 1-way direct & travel distances from subdision of storey spaces

Escape routes AB, AC are considered two-way direct travel. Escape routes DE, FG are considered one-way direct travel distances.

c. For the purpose of this clause, the most remote point from which the travel distance is measured shall be taken as being 400mm from the enclosure walls of the room or space.

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d. In the case of a residential apartment or maisonette, the travel distance shall be determined based on the provisions under Cl.9.2.1a.(5).

e. Where area of refuge is provided in lieu of required exits, travel distance shall be measured to the exit door at the corridor leading to the area of refuge.

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Explanations & Illustrations

Clause 2.2.6e. : Determination of travel distance

Where an area is designated as ‘area of refuge’ (Building B in Figure 2.2.6e., it must have adequate provision of exit facility and shall be adequate in size to hold the occupant load it receives from the floor area (Building A) it serves, allowing at least 0.3m² per person. Area of refuge acts as a temporary holding area allowing the occupants more time for evacuation. Hence, it shall be protected from the fire and smoke risk from building A via the provision of cross-ventilated bridges or external corridors.

Reference shall also be made to Cl.1.4.9 and Cl.2.2.15 for more explanations and details on the area of refuge.

Fg.2.2.6e-1

Figure 2.2.6e. Area of refuse located in other compartment
of the same building connected through a linkway/bridge

Where an area is designated as ‘area of refuge’ (Building B in Figure 2.2.6e. – 1 & 2), it must be adequate in size to hold the occupant load it receive from the floor area (Building A) which it serves as area of refuge. Area of refuge acts as a temporary holding area allowing the occupants more time for evacuation. Hence, it shall be protected from the fire and smoke risk from Building A via the provision of cross-ventilated bridges or external corridors.

While some conditions for the area of refuge is given below, reference shall also be made to Cl.1.4.9 and Cl.2.2.15 for more explanations and details on the area of refuge.

Fg.2.2.6e-2

Figure 2.2.6e. - 2 : Area of refuge located in other building
connected through a linkway/bridge

Lines EA and ED are taken as two-way direct distance measurements.

General conditions for area of refuge

a. Occupant Load for area of refuge to be based on 0.3m² per person.

b. Each connecting area shall have at least one protected staircase or exit facility of adequate width discharging at ground level.

c. Access door to area of refuge shall be kept accessible at all times

d. Door No 1, {in Figure 2.2.6e. – 2} leading to area of refuge can also be treated as a required exit from the area served by it, and hence travel distance can also be measured to this door.

Fg.2.2.6e-3

Figure 2.2.6e. - 3 : Area of refuge located in other building connected through an external corridor

General conditions for area of refuge

a. Area of Refuge shall be adequate in size to hold the occupant load it receives from Building A, in addition to its own occupant load calculated on the basis 0.3m² per person.

b. Each connecting area or floor served by an area of refuge shall have at least one protected staircase or exit facility of adequate width discharging at ground level.

c. Access door to area of refuge shall be kept accessible at all times.

d. Door D & E, {in Figure 2.2.6e. – 2 & 3 respectively} leading to area of refuge can also be treated as a required exit from the area served by it, and hence travel distance can also be measured to these doors.

f. Where permitted under Cl.2.3.3 for exit staircases to be entered without the provision of an exit door, the travel distance shall be measured to a position where the exit door would be installed if otherwise required.

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g. Ancillary office within other purpose groups

Where an ancillary office is housed within a space belong to other Purpose Groups, the travel distance requirement for the ancillary office is allowed to be based on PG IV, provided:

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(1) the ancillary office is fire compartmented from spaces belonging to the other purpose groups; and

(2) the ancillary office occupants shall have access to exit(s) within the ancillary office compartment leading to direct discharge at ground level into an external space, exit staircase, or internal/ external exit passageway.

2.2.7 Minimum width of exit access door, exit door or other exit facilities

a. No exit, exit staircase or other exit facilities shall be narrower than the minimum width requirement as specified under Table 2.2A. The minimum clear width of an exit door/ exit access opening shall be not less than 850mm.

Effective Date: 1 Mar 2022

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Clause No.	Amendment Date	Effective Date	Clause Status	Clause Before Amendment	Circular Date	Download Circular
2.2.7a.	1 Mar 2022	1 Mar 2022	Clarification	No exit, exit staircase or other exit facilities shall be narrower than the minimum width requirement as specified under Table 2.2A. The minimum clear width of an exit door opening shall be not less than 850mm.	1 Mar 2022	Download

b. Exit access doors serving a room with an occupant load of not more than two persons shall not be less than 610mm in clear width.

c. A single leaf swing door along the means of egress shall not exceed 1.25m in clear width.

R Rationale - Clause 2.2.7c

The purpose of controlling the width of single leaf door is to discourage the use of bigger, heavier leaf doors. This is because there is risk of door sagging and thus require more effort to open the door. To overcome it, 2-leaf doors should be used in larger openings instead of single leaf swing door.

2.2.8 Maximum width of exit staircases

R Rationale - Clause 2.2.8

The purpose of limiting the maximum effective exit capacity of an exit staircase is to prevent concentration of evacuees at any point of the exit. The consequence of permitting exit staircase without capacity limits could be disastrous if that staircase were rendered unusable in an emergency situation. Dividing staircase into segments not wider than 2m enables better crowd control and orderly evacuation in times of emergency.

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a. The maximum width of exit staircases shall be not more than 2m. Where staircases exceed 2m in width, handrails shall be used to divide the staircase into sections of width not less than 1m or more than 2m.

b. For the purpose of determining the exit capacity of a staircase that is wider than 2m that forms part of the required means of escape from any storey of the building, that part of its width in excess of 2m shall not be taken into account.

2.2.9 Measurement of width

R Rationale - Clause 2.2.9

The allowance of 80mm projection of handrail is considered acceptable as the projection would normally occur at the waist-height of a person. Therefore, it is unlikely to affect the egress within a protected staircase.

The measurement of width referred to under Cl.2.2.7 and Cl.2.2.8 shall be the clear width, including the width of plinth to balustrade or parapet wall:

a. For an exit staircase

The clear width shall be measured between:

(1) the finished surfaces of the walls, if the staircase is enclosed on both sides by walls only, or

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(2) the finished surface of the wall and the inner side of the balustrade, if the staircase has a wall on one side and a balustrade on the other side, or

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(3) the inner sides of the balustrades if the staircase has balustrades on both sides.

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Note: The projection of handrail into the clear width of a staircase shall not exceed 80mm on each side of the staircase. If the projection exceeds 80mm, the clear width of the staircase shall be measured from the inner sides of the handrails.

b. For an exit door

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(1) In the case of an exit door having a single leaf door, the opening shall be measured between the edge of the door jamb and the surface of the door when opened at an angle of 90°. See Diagram 2.2.9b..

(2) In the case of a 2 leaf exit door fitted with an approved automatic flush bolt, the clear openings shall be measured between the surface of one leaf to the other door leaf when opened at an angle of 90°.

(3) If one of the door leaves is bolted to the door frame and/ or floor by a manually operated bolt, this door leaf shall not be considered for the purpose of determining the exit capacity of the door. The opening of the other door leaf shall have a clear width of not less than 850mm, measured between the edge of the bolted door leaf and the surface of the other door leaf, when opened at an angle of 90°.

(4) Door hardware and handrails which do not protrude more than 80mm into the clear width of exit opening can be disregarded.

2.2.10 Number of exits from rooms and spaces

There shall be at least two door openings remote from each other which lead to exits from every room or enclosed space in which the total occupant load exceeds the maximum permissible occupant load for one door as listed in the table below:

TABLE 2.2.10 - PERMISSIBLE OCCUPANT LOAD FOR ONE DOOR
Type of Occupancy	Max. Occupant Load
High hazard	25
Patient accommodation area	50
Classrooms	50
Godowns, stores, and factories not of high hazard type	50
Assembly	50
Note: (a) The number and minimum width of exits for rooms and spaces with occupancy of more than 50 persons shall comply with provisions in Table 9.7.3a. for assembly occupancy (b) For residential occupancy, see Cl.9.2 (c) For healthcare occupancy, see Cl.9.3.2 (d) For office/shop/factory/warehouse occupancy, see Cl.9.4, Cl. 9.5, Cl.9.6, and Cl. 9.8 (e) For hotels, see Cl.9.7.2 (f) For assembly occupancy, see Cl.9.7.3

2.2.11 Number of exit staircases or exits per storey

Effective Date: 1 Sep 2024

R Rationale - Clause 2.2.11

Where possible, occupants should not be denied of alternate egress to an exit staircase. By having minimum two exit staircases, it provides an alternative for occupants to access either. This clause also addresses exit provision for non-habitable roofs and incorporates fixed ladder and access hatches requirements.

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Amendment History

2.2.11

Clause No.	Amendment Date	Effective Date	Clause Status	Clause Before Amendment	Circular Date	Download Circular
2.2.11		16 Jun 2016	Revised, extracted from SCDF's circular		15 Dec 2015	-
2.2.11 (dated 25 Aug 2023)	25 Aug 2023	25 Aug 2023	Revised/Clarification	2.2.11 Number of exit staircases or exits per storey There shall be at least two independent exit staircases or other exits from every storey of a building, unless otherwise permitted under other subsequent provisions of the Code. For non-habitable roof, at least one exit staircase shall be provided. Where the area of non-habitable roof is large and one-way travel distance to the exit cannot be met, an additional cat/ship ladder adequately separated in accordance with Cl.2.3.12 and leading to the circulation area of the floor below shall be provided. All access hatches, if provided, shall be readily accessible from the roof. Access hatch opening shall have a minimum clear width of 1m in diameter. The travel distances can be based on that for a sprinkler protected building for roof areas which are open-to-sky. For protruding structures above the non-habitable roof, namely exit staircase shaft and lift motor room is exempted from this clause.	25 Aug 2023	Download
2.2.11( dated 1 Sep 2024)	1 Sep 2024	1 Sep 2024	Relaxation	2.2.11 Number of exit staircases or exits per storey ……....................................................................... Exception: a. ……. b. ……. c. ……	1 Mar 2024	Download
2.2.11( dated 15 Sep 2020)	15 Sep 2020	15 Sep 2020	Clarification	Number of exit staircases or exits per storey There shall be at least two independent exit staircases or other exits from every storey of a building, unless otherwise permitted under other subsequent provisions of the Code. For non-habitable roof, at least one exit staircase shall be provided. Where the area of non-habitable roof is large and one-way travel distance to the exit cannot be met, an additional cat/ship ladder adequately separated in accordance with Cl.2.3.12 and leading to the circulation area of the floor below shall be provided. All access hatches, if provided, shall be readily accessible from the roof. Access hatch opening shall have a minimum clear width of 1m in diameter. The travel distances can be based on that for a sprinkler-protected building for roof areas which are open-to-sky.	15 Sep 2020	Download

There shall be at least two independent exit staircases or other exits from every storey of a building, unless otherwise permitted under other subsequent provisions of the Code.

Exception

a. For non-habitable roof that is able to comply with one-way travel distance, at least one exit staircase shall be provided. The travel distances for roof areas which are open-to-sky shall be based on the requirements for sprinkler-protected buildings.

b. For non-habitable roof that is unable to comply with one-way travel distance to the exit staircase, an additional cat/ ship ladder adequately separated in accordance with Cl.2.3.12 and leading to the circulation area of the floor below shall be provided. All access hatches, if provided, shall be readily accessible from the roof. Access hatch opening shall have a minimum clear width of 1m in diameter. The travel distances for roof areas which are open-to-sky shall be based on the requirements for sprinkler-protected buildings.

c. Roof of the protruding structures above the non-habitable roof, namely exit staircase shafts and lift motor rooms.

d. For green roofs which are accessible for maintenance purposes only, the means of access shall comply with Cl.10.2.1b.(1)(a).

2.2.12 Location of exits & access to exits

Effective Date: 15 Mar 2021

Clause No.	Amendment Date	Effective Date	Clause Status	Clause Before Amendment	Circular Date	Download Circular
2.2.12b.	15 Mar 2021	15 Mar 2021	Revised	2.2.12b. Every occupant or tenant within a building or storey of a building shall have direct access to the required exit or exits without the need to pass through the spaces or rooms occupied by other occupants or tenants	15 Sep 2020	Download

All exits and access facilities shall be required to comply with all of the following:

a. Exits and access facilities shall be clearly visible or their locations shall be clearly indicated and shall be kept readily accessible and unobstructed at all times.

b. Every occupant within a building or storey of a building shall have direct access to the required exit or exits without the need to pass through another room(s) or other tenanted space(s). Where direct access to the required exit or exits of the storey is not possible, occupants shall only be allowed to pass through a maximum of one other room or space belonging to the same tenant with the following conditions being complied with:

(1) the exit access door separating the rooms or spaces which the egress route passes through shall only be fitted with electromechanical device designed in accordance with Cl.2.3.9k.(2);

(2) the doorway of the exit access door shall not be blocked/obstructed and be kept clear at all times.

(3) warning signs of wording “Exit Access Door - Keep Clear” shall be placed prominently on both sides of the exit access door, and

(4) the egress paths through the exit access door shall be suitably demarcated.

Effective Date: 15 Mar 2021

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Clause No.	Amendment Date	Effective Date	Clause Status	Clause Before Amendment	Circular Date	Download Circular
2.2.12b.	15 Mar 2021	15 Mar 2021	Revised	2.2.12b. Every occupant or tenant within a building or storey of a building shall have direct access to the required exit or exits without the need to pass through the spaces or rooms occupied by other occupants or tenants	15 Sep 2020	Download

c. When more than one exit is required from any room or space or a storey of a building, each exit shall be placed as remote as possible from the other as permitted under Cl.2.3.12a., b., c. or d..

R Rationale - Clause 2.2.12c

To reduce the possibility of more than one exit staircase being rendered unusable simultaneously by fire or other emergency situations, the exit staircases are to be remotely located from each other.

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2.2.13 Smoke-free approach to exit staircase

Effective Date: 25 Aug 2023

R Rationale - Clause 2.2.13

The smoke-free approach is intended to act as a buffer space to minimise smoke entry into the exit staircase when used by evacuees and firefighters during a fire emergency.

Entry at every storey level (including 1st storey) to an exit staircase serving more than four storeys above ground level shall be through any one of the following:

a. An external exit passageway or external corridor

The openings for natural ventilation to the corridor shall be located such that they face and are open to any of the following:

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Explanations & Illustrations

Clause 2.2.13a. : Smoke-free approach to exit staircase

Fg.2.2.13a-1

Figure 2.2.13a. - 1

Fg.2.2.13a-2

Axonometric Section

Figure 2.2.13a. - 2

Fg.2.2.13a-3

Section

Figure 2.2.13a. - 3

External exit passageway is a protected area, which is an extension of the vertical exit staircase. It is used to overcome excessive travel distances as shown in the above figure.

The provision of smoke screen above the passageway before the staircase is to prevent smoke from entering the stairwell at ceiling level.

Main differences between external corridor, smoke-stop lobby and external exit passageway

#	External corridor	Smoke-Stop Lobby	External exit passageway
Entrance door	No fire rating	At least ½-hr fire rating	At least ½-hr fire rating
Usage	As smoke-free approach	As smoke-free approach	As extension of the vertical exit (to overcome travel distance deficiency)
Corridor/lobby – air well ventilation	Min 1.2m high opening Max 3m roof over 1m <parapet wall<1.1m Air well - Min 6m wide / area 93m²	Opening 15% of lobby area Max 9m from opening Air well - min 6m wide / area 93m²	Min 1.2m high opening Max 3m roofed over 1m<Parapet wall <1.1m Comply with Table 1.2.1A if facing air well
Cross ventilation	Min 1.2m high opening Max 3m roof over	Opening 50% of opposing wall superficial area Max 12m from opening No obstruction	Min 1.2m high opening Max 3m roof over 1m<Parapet wall <1.1m Comply with Table 1.4.2
Vent openings btw unit & corridor/smoke-stop lobby	Above 1100mm from finished floor level of corridor	No opening allowed	Above 1800mm from finished floor level of passageway
Risers	No fire rating for shaft door	Fire rated shaft and doors	No services allowed
Exposed M&E services (Cl 3.9.6)	Service allowed only if enclosed with fire rated enclosure	No services allowed unless enclosed in 1hr rated enclosure	No services allowed

It is important that exit staircases are kept free of any smoke at all times, especially in times of a fire emergency, as it is the main essential means for evacuating occupants from the building. To facilitate this smoke free environment, a buffer zone that can quickly dispel any smoke entering it from occupied spaces to the external space is created before entry into the staircases. Hence the passage or route through these areas (or buffer zone) which is relatively free of smoke for safe escape for the occupants and leading to the exit staircases is referred here as the smoke free approach.

Fg.2.2.13a-4

Figure 2.2.13a. - 4

Travel Distance measurement, as shown by line AB in Diagram 2.2.13 (a)(iii)-4, in the external corridor situation is taken from any remote point within the occupied area to the exit door of the exit staircase.

External Exit passageway, as shown in Diagrams 2.2.13 (a) – 2 below, is a protected area, which is an extension of the vertical exit staircase. It is used to overcome excessive travel distances.

A smoke screen may be provided above the passageway before the entry into the exit staircase to prevent smoke at the ceiling level from entering the stairwell.

Fg.2.2.13a-5

Figure 2.2.13a. - 5 : Approach to exit staircase through external exit passageway

Fg.2.2.13a-6

Figure 2.2.13a. - 6

The height of parapet walls of corridors alongside an air-well shall not exceed 1000mm measured from its finished floor level. It shall be noted here that the ventilation openings for exit staircases in the above design layout shall not open into the air-well.

(1) an external space complying with Cl.2.3.11, or

(2) a street, service road or other public space which is open to the sky, or

(3) an air well which opens vertically to the sky and has a minimum width of 6m and a superficial plan area of not less than 93m², except that for external corridors, it shall comply with the requirements of Cl.2.3.10.

b. Smoke-free/ fire lift lobby

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(1) A smoke-free lobby shall be separated from the adjoining areas of the building by a wall having 1-hr fire resistance.

(2) The exit access door shall have ½-hr fire resistance fitted with automatic self-closing device conforming to the requirements of Cl.3.9.2.

(3) The design of a smoke-free lobby shall be such as not to impede movement of occupants through the escape route.

(4) The floor area of a smoke-free lobby shall be at least 3m² and with minimum clear width of 1.2m. If a smoke-free lobby also serves as a fire lift lobby, the floor area shall be not smaller than 6m² and with minimum clear width of 2m.

(5) The floor shall be graded from the lift door towards the lobby door with a fall not exceeding 1 in 200.

(6) A smoke-free lobby, including fire lift lobby, which acts as buffer space for entry into the exit staircase and use by firefighters during emergency, shall be maintained as common property.

(7) A smoke-free lobby shall be ventilated through any of the following:

R Rationale - Clause 2.2.13b.(7)

Access routes to exits shall be kept smoke-free by a smoke-stop lobby, either naturally or mechanically ventilated, in order to provide a reliable means of escape for occupants and access for firefighters.

(a) Permanent fixed ventilation openings which are located in the external wall of the lobby and have a total area of not less than 15% of the floor area of the lobby.

Each opening shall not be less than 1m² and shall abut an external space or air well, each having a minimum clear area of 93m² and minimum width of 6m and without obstruction vertically throughout the airspace for ventilation. No part of the lobby floor area shall be more than 9m away from the air well or external space.

Effective Date: 10 May 2019

R Rationale - Clause 2.2.13b.(7)(a)

The minimum width of 6m and a superficial plan area of not less than 93m² of an air well have been validated through fire engineering study to provide effective smoke ventilation for a smoke-stop lobby.

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Clause No.	Amendment Date	Effective Date	Clause Status	Clause Before Amendment	Circular Date	Download Circular
2.2.13b(7)(a)	10 May 2019	10 May 2019	Clarification	Permanent fixed ventilation openings which are located in the external wall of the lobby and have a total area of not less than 15% of the floor area of the lobby. Each opening shall not be less than 1m2 and shall abut an external space or air well, having a minimum clear area of 93m2 and minimum width of 6m and without obstruction vertically throughout the airspace for ventilation. No part of the lobby floor area shall be more than 9m away from the air well or external space.	10 May 2019	Download

(b) Mechanical ventilation, except for PG II buildings, which complies with the requirements in Chapter 7.

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(c) Cross-ventilated corridor/lobby which complies with all of the following:

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(i) The corridor/lobby shall have fixed ventilation openings abutting an external space. The ventilation openings shall be located on opposite sides of the corridor/lobby at high level and shall not be less than 50% of the superficial area of the opposing external walls.

(ii) No part of the floor area of the corridor/lobby shall be at a distance of more than 12m from the ventilation openings.

(iii) The distance of 12m can be measured along the internal corridor via the intermediate ventilation opening to the external space, provided there is no unprotected openings in the walls along the path to the external space. The intermediate ventilation opening shall not be less than 2m in width and 1.2m in height and the width of the path to the external space shall not be less than 2m.

Note: For residential buildings of habitable height more than 24m with single exit staircase, the requirements for the cross-ventilated corridor/lobby stipulated in Cl.9.2.1a.(4)(e) shall be complied with.

c. Exception

Effective Date: 25 Aug 2023

(1) The omission of the smoke-free lobby required under Cl.2.2.13b. leading to the exit staircase of any building exceeding four storeys is allowed under any of the following situations, provided the door opening into the exit staircases shall have 1-hr fire resistance rating and fitted with an automatic self-closing device to comply with the requirements of Cl.3.9.2:

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(a) Where the internal exit staircase is provided with pressurisation up to a habitable height of 24m in compliance with the requirements of Chapter 7;

R Rationale - Clause 2.2.13c.(1)(a)

The positive pressure in the pressurised staircase acts to force smoke away from the doorway of the exit staircase when the exit door is opened, thereby preventing smoke from entering the exit staircase.

(b) Where an external exit staircase is constructed to comply with Cl.2.3.3b.;

R Rationale - Clause 2.2.13c.(1)(b)

Open sides of an external exit staircase allow for quick dispersal of any smoke infiltrated through the doorway when the door is opened. As such, a smoke-stop lobby before the external exit staircase is not necessary.

(c) In an open-sided car park floor where cross-ventilation is provided in accordance with Cl.3.2.8a. & b., the fire door to the exit staircase can be ½-hr fire-rated.

R Rationale - Clause 2.2.13c.(1)(c)

The doorway before the exit staircase is unlikely to be smoke logged during a fire emergency. This is because the substantial ventilation openings along the perimeter of the car park allow for quick dispersal of smoke.

(d) On M&E floor of headroom not exceeding 1.5m.

(2) The omission of a smoke-free lobby to exit staircases shall not be allowed under any of the following situations:

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Explanations & Illustrations

Clause 2.2.13c.(2) : Smoke-free approach to exit staircase

Fg.2.2.13c(2)-1

Figure 2.2.13c.(2) - 1

The positive pressure in the pressurised staircase Figure 2.2.13c.(2) - 1 acts to force smoke away from the doorway of the staircase when that exit door is opened, thereby preventing smoke entry into the staircase. The above exemption shall apply to building of which the habitable height does not exceed 24m. This is to meet the requirements under Cl.2.3.3d.(8) and Cl.7.2.1a. which specifically require all internal staircases of building having a habitable height exceeding 24m to be pressurised. If the habitable height of the building exceeds 24m, the entry to the internal exit staircase shall be through smoke-stop lobby or external approach.

Fg.2.2.13c(2)-2

Figure 2.2.13c.(2) - 2

In the case of the cross-ventilated staircase (Figure 2.2.13c.(2) - 2), its open sides allow for quick dispersal of any smoke infiltrating the doorway when opened.

Hence, in both these situations, it is possible to achieve a relatively safe smoke free environment in the exit staircase for facilitating escape for its occupants. Another reason to note is that these premises warrant emergency plans and fire drills to familiarise its occupants on their procedural actions in fire emergencies.

Fg.2.2.13c(2)-3

Figure 2.2.13c.(2) - 3

Fg.2.2.13c(2)-4

Figure 2.2.13c.(2) - 4 : Open-sided multi-storey car park

Fg.2.2.13c(2)-5

Section

Figure 2.2.13c.(2) - 5 : Open-sided multi-storey car park

The above requirement exempts the provision of smoke-stop lobby to exit staircases in cross-ventilated car park buildings. In Figure 2.2.13c.(2) - 4, the space before the exit staircases can satisfactorily achieve a smoke free environment. The doors to exit staircases shall be minimum ½-hr fire rated.

Fg.2.2.13c(2)-6

Figure 2.2.13c.(2) - 6 : Situation where no exemption is granted -
internal staircase serving building exceeding 24m habitable height

Fg.2.2.13c(2)-7

Figure 2.2.13c.(2) - 7 : Situation where no exemption is granted -
when adjacent to a fire lift

No exemption of the smoke-stop lobby will be granted for the exit staircase adjacent to a fire lift. The firefighters would require the lobby space as a ‘staging’ point in their fire fighting operations, prior to entering into the affected areas, in fire emergencies.

(Note: Cl 2.2.13c.(2) is not applicable to buildings under PG VII)

Smoke-stop lobby is exempted for the arrangements shown in Figures 2.2.13(c)(2) – 1 & 2 in buildings of PG II, IV, V, VI & VIII up to 60m high. The reasons for this relaxation being:

Any internal exit staircase without provision for natural ventilation and in habitable height not exceeding 60m will be provided with dedicated pressurization system. The door opening into the staircase is required to have minimum 1-hr fire resistance rating.

Partially enclosed staircase is required to be cross-ventilated having uninterrupted external openings of minimum 50% of the plan area of the staircase.

Fg.2.2.13c(2)-8

Section

Figure 2.2.13c.(2) - 8 : Fixed unobstructed ventilation openings

Fg.2.2.13c(2)-9

Section

Figure 2.2.13c.(2) - 9

Likewise a cross-ventilated car parking storey in Figure 2.2.13c.(2) - 9 is exempted from the provision of smoke-stop lobby to exit staircase. However, the upper storeys above the car parking floors are not exempted from provision of Cl 2.2.13c.(2).

(a) Where the building exceeds four storeys and belongs to PG III or VII.

(b) Where the internal exit staircase, which is provided with pressurisation, exceeds the habitable height of 24m.

(c) Where the exit staircase is adjacent to a fire lift as required in Chapter 6.

2.2.14 Smoke-free approach to exit staircase in basement

Effective Date: 1 March 2024

R Rationale - Clause 2.2.14

Access to exits must be free of smoke and be available to building occupants at all times. Therefore, a reliable means of escape for occupants and access for firefighters shall be provided via smoke-free access route and staircases. For this reason, providing mechanical air pressuring systems to smoke-stop lobbies and exit staircases is needed to prevent smoke infiltration.

Amendment History

2.2.14

Clause No.	Amendment Date	Effective Date	Clause Status	Clause Before Amendment	Circular Date	Download Circular
2.2.14	25 Aug 2023	1 March 2024	Revised/Clarification	2.2.14 Smoke-free approach to exit staircase in basement a. In a building comprising more than four basement storeys, the entry to exit staircases serving the basement storeys at every basement storey level shall be through smoke-free lobbies, one of which shall be designated as a fire lift lobby. The exit staircase connecting to the fire lift lobby shall be pressurised to comply with the requirements in Chapter 7. b. In a building comprising two, three, or four basement storeys, entry at every basement storey level to at least one of the exit staircases serving the basement storeys shall be through a smoke-free lobby. Where only one smoke-free lobby is provided, it shall be required to serve as a fire lift lobby. c. Smoke-free lobbies in basement occupancies shall be required to comply with the relevant provisions under Cl.2.2.13b. and shall be mechanically ventilated to comply with the requirements in Chapter 7.	25 Aug 2023	Download

a. In a building comprising single basement storey, the entry to exit staircases need not be through smoke-free lobbies.

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Amendment History

2.2.14a

Clause No.	Amendment Date	Effective Date	Clause Status	Clause Before Amendment	Circular Date	Download Circular
2.2.14	25 Aug 2023	1 March 2024	Revised/Clarification	2.2.14 Smoke-free approach to exit staircase in basement a. In a building comprising more than four basement storeys, the entry to exit staircases serving the basement storeys at every basement storey level shall be through smoke-free lobbies, one of which shall be designated as a fire lift lobby. The exit staircase connecting to the fire lift lobby shall be pressurised to comply with the requirements in Chapter 7. b. In a building comprising two, three, or four basement storeys, entry at every basement storey level to at least one of the exit staircases serving the basement storeys shall be through a smoke-free lobby. Where only one smoke-free lobby is provided, it shall be required to serve as a fire lift lobby. c. Smoke-free lobbies in basement occupancies shall be required to comply with the relevant provisions under Cl.2.2.13b. and shall be mechanically ventilated to comply with the requirements in Chapter 7.	25 Aug 2023	Download

b. In a building comprising two, three or four basement storeys, entry at every basement storey level to at least one of the exit staircases serving the basement storeys shall be through a fire lift lobby even though the exit staircase is not required to be served by a fire lift. However, where the depth of the basement exceeds 9m below the average grade level and fire lifts are required in accordance with Cl.6.6.4b.(3), the entries to the exit staircases with provision of fire lifts at every basement storey level shall be through fire lift lobbies.

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Amendment History

2.2.14b

Clause No.	Amendment Date	Effective Date	Clause Status	Clause Before Amendment	Circular Date	Download Circular
2.2.14	25 Aug 2023	1 March 2024	Revised/Clarification	2.2.14 Smoke-free approach to exit staircase in basement a. In a building comprising more than four basement storeys, the entry to exit staircases serving the basement storeys at every basement storey level shall be through smoke-free lobbies, one of which shall be designated as a fire lift lobby. The exit staircase connecting to the fire lift lobby shall be pressurised to comply with the requirements in Chapter 7. b. In a building comprising two, three, or four basement storeys, entry at every basement storey level to at least one of the exit staircases serving the basement storeys shall be through a smoke-free lobby. Where only one smoke-free lobby is provided, it shall be required to serve as a fire lift lobby. c. Smoke-free lobbies in basement occupancies shall be required to comply with the relevant provisions under Cl.2.2.13b. and shall be mechanically ventilated to comply with the requirements in Chapter 7.	25 Aug 2023	Download

c. In a building comprising more than four basement storeys, the entry to exit staircases serving the basement storeys at every basement storey level shall be through smoke-free lobbies or designated fire lift lobbies in accordance with Cl.6.6.4b.(3).

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Amendment History

2.2.14c

Clause No.	Amendment Date	Effective Date	Clause Status	Clause Before Amendment	Circular Date	Download Circular
2.2.14	25 Aug 2023	1 March 2024	Revised/Clarification	2.2.14 Smoke-free approach to exit staircase in basement a. In a building comprising more than four basement storeys, the entry to exit staircases serving the basement storeys at every basement storey level shall be through smoke-free lobbies, one of which shall be designated as a fire lift lobby. The exit staircase connecting to the fire lift lobby shall be pressurised to comply with the requirements in Chapter 7. b. In a building comprising two, three, or four basement storeys, entry at every basement storey level to at least one of the exit staircases serving the basement storeys shall be through a smoke-free lobby. Where only one smoke-free lobby is provided, it shall be required to serve as a fire lift lobby. c. Smoke-free lobbies in basement occupancies shall be required to comply with the relevant provisions under Cl.2.2.13b. and shall be mechanically ventilated to comply with the requirements in Chapter 7.	25 Aug 2023	Download

d. Smoke-free and fire lift lobbies in basement occupancies shall be required to comply with the relevant provisions under Cl.2.2.13b. and shall be mechanically ventilated to comply with the requirements in Chapter 7.

Amendment History

2.2.14d

Clause No.	Amendment Date	Effective Date	Clause Status	Clause Before Amendment	Circular Date	Download Circular
2.2.14	25 Aug 2023	1 March 2024	Revised/Clarification	2.2.14 Smoke-free approach to exit staircase in basement a. In a building comprising more than four basement storeys, the entry to exit staircases serving the basement storeys at every basement storey level shall be through smoke-free lobbies, one of which shall be designated as a fire lift lobby. The exit staircase connecting to the fire lift lobby shall be pressurised to comply with the requirements in Chapter 7. b. In a building comprising two, three, or four basement storeys, entry at every basement storey level to at least one of the exit staircases serving the basement storeys shall be through a smoke-free lobby. Where only one smoke-free lobby is provided, it shall be required to serve as a fire lift lobby. c. Smoke-free lobbies in basement occupancies shall be required to comply with the relevant provisions under Cl.2.2.13b. and shall be mechanically ventilated to comply with the requirements in Chapter 7.	25 Aug 2023	Download

2.2.15 Area of refuge and exit reduction

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When a floor area has access to area(s) of refuge in compliance with all of the following requirements in this Clause, the occupant load for which vertical exits are to be accounted for the floor area can be reduced to half when one area of refuge is provided and to one third when two or more areas of refuge are provided.

a. An area of refuge shall be adequate in size to hold the occupant load it receives from the floor area it serves as provision for required exit, in addition to its own occupant load calculated on the basis of 0.3m² per person except for healthcare occupancies when the occupant load shall comply with the provisions under Cl.9.3.2b.(4).

b. An area of refuge shall be provided with at least one staircase for use by the occupants to gain access to other exit staircases or the ground level directly to an external space.

c. An area of refuge shall be entered through an external corridor and the room or space or area of refuge shall be separated from the corridor by a wall with at least 1-hr fire resistance rating.

d. External corridors when used as entry into an area of refuge shall conform to the requirements for external exit passageway for minimum width, changes in floor level, roof protection, enclosure on the open side and provision of opening of wall between the room or space and the exit passageway.

e. Exit doors between the room or space or area of refuge and the external corridor shall have fire resistance of at least ½-hr and be fitted with an automatic self-closing device to comply with the requirements of Cl.3.9.2.

f. Every fire compartment in which exit reduction is permitted in connection with area of refuge shall have in addition to exit through the area(s) of refuge at least one exit staircase complying with Cl.2.3.3.