Interpretation of Passive Fire Requirements in the UBBL 1984
Transcript of Interpretation of Passive Fire Requirements in the UBBL 1984
Interpretation of Passive Fire Requirements
in the UBBL 1984
Ar Chong Lee Siong APAM MIFireE
PAM CPD 3 November 2012
Uniform Building By-Laws 1984
is a
“PRESCRIPTIVE” BUILDING CODE
•Compliance with this code is a requirement by law •Sets rules and regulations on the application of the code •Provides pre-determined prescriptions
The prescriptions are absolute : no smaller than…….. no bigger than…….. no shorter than…… no longer than…… or no less than and no more than.
CONCEPTS OF FIRE SAFETY
1 EVACUATION
2 PASSIVE CONTAINMENT
3 ACTIVE INTERVENTION
4 ACCESS FOR FIRE FIGHTING AND RESCUE
• EVACUATION
• Detection
• Alarm
• Exits
• Travel distance
• Components
• Capacity of exits
Accepted assumption in designing for safe evacuation:
“Only one fire at one location at a time”
exit
• Final exit
• ‘Alternative exits’
• Storey exit
• Horizontal exit
• Exit route
Final exit
• UBBL 133 – interpretations
• Final exit refers to the threshold that separates “still within the building” and “out of the building”. The liability of the design for evacuation from the building ends at this point.
‘Alternative exits’
• UBBL 166
• This is the primary concept for safe evacuation. Every floor space shall be provided with at least two exits on the basis that if one exit is inoperable, the other exit can serve the function.
• This ‘designing for redundancy’ principle applies to all aspects of evacuation.
Final exit
Final exit
Final exit
Alternative exits
Alternative exits
Horizontal exit
• UBBL 171
• Exits that lead to an adjacent (horizontal) separated compartment within the same floor
Horizontal exit
Protected staircase
to final exits
Compartment wall
Protected staircase
to final
exits
Horizontal exit
Storey exit
• UBBL 167, 174
• Exits from a floor which is of a different level from the final exit, or, if on the same level, a distance away from the final exit.
• A storey exit is to lead to a final exit.
Exit route
• UBBL 133 – interpretations
• UBBL 169
• the protected passage from a storey exit that leads to the final exit.
• Can include spaces that are designated as areas of refuge anywhere between the storey exit and the final exit
Travel distance • UBBL 165
• 7th Schedule
• Dead end • initial travel distance before a point where an alternative path becomes
available
• Direct distance • Stipulates that travel distance must be measured along the actual path of
travel
• Open plan • Where an actual path of travel cannot be determined, the direct distance
can be measured as a straight line direct to the exit. Permitted travel distance is then reduced to 2/3.
Evacuation : small area
Evacuation : larger area
Evacuation : multiple areas
Final exits
UBBL 165 (B) Max 15m if room < 6 pax
To comply with dead end and travel distance Max distance is 15m within room plus max allowable travel distance From door of room to final exit
Evacuation : multiple areas
Horizontal exits
storey exits
Horizontal exits
1 2 3
Horizontal exits
1 2 2
Storey exit
Storey exit
For floors up to 9m from
ground floor, mezzanine floors may be
permitted to be up
to 50% of the area of floor below.
For mezzanines above 9m from ground level,
a floor area of upto 1/3 of floor area below
may be permitted.
Diagramme 4.4.5.9.
Egress through
unenclosed openings
(mezzanines)
Permitted
Alternative
Route
components
• Exit door
• Exit discharge
• Protected corridor
• Protected staircase
• Balcony approach
• Single staircase
Exit door, exit discharge
• UBBL 173
• UBBL 186
• UBBL 193
• UBBL 133 - interpretations
• ‘Door’ refers to the physical door installed at an exit, and all its functional components e.g. locksets, latches, hinges and closers
• ‘discharge’ refers to the ‘doorway’ or threshold of an exit
Exit door, exit discharge • Not all fire rated doors are exit doors
• Not all exit doors need to be fire doors
• Not all doors need to be exit doors
• Not all doors can be exit doors
• Exit doors must always be able to be opened (without undue effort) at all times
• Exit discharge must always allow the passage of people at all times
• ‘Exit’ in this context means storey exit, horizontal exit or final exit
Evacuation : separation of routes
Final exit Final exit
Protected corridor, protected staircase
• UBBL 133-interpretations
• UBBL 157, 189, 190, 191
• While not expressed, it is inferred from the UBBL that all components that form the Exit Route shall be of protected construction.
• Using the same inference, ‘protected’ shall mean ‘enclosed’, ‘separated’ or ‘isolated’
section B-B 2m
2m
2m
2m
2m
2m
Openings for toilets
can be formed
9m Opening more than
9m below can be
formed
Fixed openings
with wired glass
allowed
section a-a
Zone where
opening
not permitted
PLAN
A
A
B B Protection for External
Escape Staircase
By-Law 191 ensures that an
external staircase used for escape
purposes will remain protected
from fire exposure originating from
the building. Therefore, a zone of
protection is extended from the
staircase both upwards and
downwards to ensure safe passage
during a fire.
The following illustrations show
the zone where no opening shall be
formed or only toilets or other
protected area openings or
openings with wired glass and kept
permanently closed can be allowed
to be formed.
Single stair
• UBBL 194
• Special provision for the common ‘shop-house’ design
• Usage limited to shop (ground floor only), residential or office.
• Uppermost floor level limited to 12m
By-Law 194 stipulates when a single staircase may be permitted. Essentially, this is only
allowed where the occupancy above ground level is confined to either domestic or office
purposes. The ground floor may be used for shops or car parks. (shop offices, shop
houses)
All elements of structure shall have a FRP of not less than one hour except the enclosure
for the staircase at the ground floor where the wall shall have an FRP of not less than
two hours, assuming the ground floor will not be used for residential purposes.
12m
max.
12m
max.
Diagram 4.4.8.2.
Maximum travel distance
not more 12m
Assumed Room of occupancy < 6
Shop or car park
Diagram 4.4.8.1.
Height of topmost floor
of building with single
staircase
Height of
topmost floor < 12m
Domestic or office use
SINGLE STAIRCASE PROVISION UBBL 194
Capacity of exits
• UBBL 7th Schedule
• UBBL 175, 176, 178
• Occupant load
• Exit width
• Application of horizontal exit
Sample calculation
Scenario 1: upper floor assembly area in an institutional building
50m
20m
Stair A Stair B
Lobby C
Sample calculation
Scenario 2: upper floor assembly area in an institutional building
35m
Stair A Stair B
Lobby C
20m
15m
door D
Final exit
Exit route
horizontal exit
storey exit
Final exit 250 pax
400 pax
200 pax 150 pax
300 pax
200 pax
• Size limitations of ‘compartments’
• Fire Resistance Ratings of ‘elements of structure’
Compartmentation
• To contain the spread of fire from point of origin
• To limit the potential size of the fire
• To separate areas of different levels of hazard
• To separate areas for safe exit, evacuation or refuge
• To limit threat to the structural integrity of the building
• To allow sufficient time for safe evacuation, active extinguishment of fire and rescue.
Compartmentation
Accepted assumption in designing for safe evacuation:
“Only one fire at one location at a time”
Primary objective of compartmentation:
“To contain the one fire within the one location at all times”
COMPARTMENTS, ELEMENTS OF STRUCTURE AND FRP
215(2) : reference to height, by building only
215(1) : reference to elements of structure, by building, or by compartments
137 : floor to floor compartment for buildings > 30m height
138(b) : floor and walls separating flats
138(c) : floor and walls separating purpose group
138(d) : floor separating basements
Service apts
Offices
Shops
Carpark
Cineplex
Max 25mm (/)
FIRE APPLIANCE ACCESS
Refers to an area “Access Way” specifically allocated for the
parking of Bomba appliances during fire fighting and rescue operations. UBBL 140 “Access Way” (street, road or open space) is to be provided as a proportion of the perimeter of the building, with reference to the volume of the building.
EXTERNAL ACCESS
Access for emergency and rescue vehicles, equipment and personnel
•Roads •Pavements •Parking
Availability of water : •Hydrants •Storage tanks •Lakes, rivers, ponds
And access to fire fighting systems in the premises
Clarity of : •Type of building and function •Configuration of building •Location of fire control panel •Location of breaching inlets and pump rooms
AT THE PREMISES
Access into the building •Protected passage •Protected stairs •Firemen’s lift •Fire fighting lobby
Pressurised Hydrant System
Sprinkler System
Dry Riser system
Wet Riser System
External source of water •Hydrants •Lakes, Ponds, Pools, rivers •Fire Tenders
Fire Fighting Appliance on ‘Access Way’
Internal Systems •Sprinklers •Hose reels •Dry/Wet Risers
Breaching Inlet
Vehicles in use by JBPM : •Motorcycle •Terrain buggy •Rapid Fire Rescue Tender •Fire Rescue Tender •Turntable ladder •Hydraulic platform •Hazmat
Example of Fire Fighting Access Way
Fire appliance access level and Access Way
Access Way at upper ground level
13,000 m3 (1/6)
8,600m3 (1/6)
36,000m3 (1/4)
Access way at appliance access level
Access way at upper ground level
Access road / ramp Access road / ramp
Access ramp
Access ramp
Command center Breaching inlet Pump room access
Note: Turning provision required for fire appliances if dead end access
exceeds 18 m.
Turning provision can be in the form of hammer-head or turning
circle
Building volume
7,001 cu m
to 28,000 cu m
D
A
B
Isolated site/location
with no adjacent
property/building.
X => 1/6 (A+B+C+D)
Fire appliance
access X
C
C => 1/6 (A+B+C+D)
Appliance access from main road is sufficient if the building volume does not
exceed 28,000 m3.
In the event the 6 m back lane is accessible by fire fighting appliances and the
building volume exceeds 28,000 m3 but is less than 56,000 m3, then,
A + C => 1/4 (A+B+C+D)
Building volume
7,001 cu m
to 28,000 cu m
City/Built up location
with adjacent buildings D
A
B
C
Accessible perimeter
of building
Main road used for
appliance access
if not less than 12m wide
Pavement
6m back lane
D
A
B
D
A
C
Access
road
> 18m
Building volume
56,001 cu m to
84,000 cu m
min. 6m
B + C => 1/2 (A+B+C+D)
C
Fire appliance access Access road
12m
B
6m back lane
accessible to fire appliance
Pavement
Access road
12m A + C => 1/2 (A+B+C+D)
D
Fire appliance
access minimum
6m width
Building volume
84,001 cu m to
112,000 cu m
A + B + C 3/4 (A+B+C+D)
A
B
C
Access road 12m
D
A
B
Building volume
84,001 cu m to
112,000 cu m
B + C + D => 3/4 (A+B+C+D)
C
Access road 12m
A
Building
volume
above
112,000 cu m
Minimum 6m width
Fire appliance access
D B
C
Access road 12m
W2
(min 6m)
L(13m)
L(13m) min. 6m W1
d1
d2
W = unobstructed width of Appliance Access
L = length of largest Fire Appliance (currently 13m)
d - cut-back distance is obtained by intersecting the imaginary corner of a building with
line A - C
The minimum permissible width of a Fire Appliance Access is 6.0m.
The minimum turning radius around corners of buildings shall be provided as follows:
Hydrants should be located:
i) away from obstructions such as street furniture (benches), phone
booths, etc.
ii) not less than 2,000mm from adjacent buildings and overhangs.
iii) between 610mm to 2,400mm from Fire Appliance Access.
iv) away from risks of vehicular damage.
v) not more than 90m apart from each other (in new buildings adjacent
to existing developments, a new hydrant within 45m radius of the new
building).
No overhangs
over hydrants
Verandah
Pavement
Access
Hydrant
Building
> 2m 0.6m to 2.4m
Thank You