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Building Services II Assignment
Module Code: BLD60503
Lecturer: Mr. Tan Hee Chai
Design of Fire Protection Systems
for High Rise Buildings in Malaysia
Group members:
Hong Kai Yin 0323361
Lau Chin Sheng 0317899
Kong Zhen Chung 0319528
Welson Lum Wei Jiunn 0319514
Yong Sing Yew 0318766
Fire Safety Requirements based on UBBL
Fire safety measures complying with the requirements of the Malaysian Uniform Building by
Laws (UBBL) 1984 for residential (Condominium).
Based on our study we noted down the important points of fire safety requirements from the
UBBL 1984 for residential.
Fire Requirements:
UBBL Section 137 - Floor in building exceeding 30 metres in height to be constructed as
compartment floor.
In any building which exceeds 30 metres in height, any floor which is more than 9 metres above
ground level which separates one storey from another storey, other than a floor which is either
within a maisonette or a mezzanine floor shall be constructed as a compartment floor.
UBBL Section 138 – Others walls and floors to be constructed as compartment walls or
compartment floor.
The following walls and floors in buildings shall be constructed as compartment walls or
compartment floors:
a) Any floor in a building of Purpose Group (Institutional)
b) Any wall or floor separating a flat or maisonette from any other part of the same
building;
c) Any wall or floor separating part of a building from any other part of the same building
which is used or intended to be used mainly for a purpose falling within a different
purpose group as set out in the Fifth Schedule to these By-laws; and
d) Any floor immediately over a basement storey if such basement storey has an area
exceeding 100 square metres.
UBBL Section 151 – Ventilation to lift shafts.
Where openings to lift shafts are not connected to protected lobbies, such lift shafts shall be
provided with vents of not less than 0.09 square metre per lift located at the top of the shafts.
Where the vent does not discharge directly to the open air the lift shafts shall be vented to the
exterior through a duct of the required FRP as for the lift shafts.
UBBL Section 152 – Opening in lift shafts.
1) Every opening in lift shaft or lift entrance shall open into a protected lobby unless other
suitable means of protection to the opening to the satisfaction of the local authority is
provided. These requirements shall not apply to open type industrial and other special
buildings as may be approved by the D.G.F.S
2) Landing doors shall have a FRP of not less than half the FRP of the hoistway structure
with a minimum FRP of half hour.
3) No glass shall be used for in landing doors except for vision in which case any vision
panel shall or be glazed with wired safety glass, and shall not be more than 0.0161
square metre and the total area of one of more vision panels in any landing door shall
be not more than 0.0156 square metre.
4) Each clear panel opening shall reject a sphere 150 millimetres in diameter.
5) Provision shall be made for the opening of all landing doors by means of an emergency
key irrespective of the position of the lift car.
UBBL Section 153 – Smoke detectors for lift lobbies.
1) All lift lobbies shall be provided with smoke detectors.
2) Lift not opening into a smoke lobby shall not use door reopening devices controlled by
light beam or photo-detectors unless incorporated with a force close feature which after
thirty seconds of any interruption of the beam causes the door to close within a present
time.
UBBL Section 160 – Fire precaution in air conditioning systems.
1) All air-conditioning ducts, including farming therefor, except ducts in detached and
semi-detached residential buildings shall be constructed entirely of non-combustible
materials and shall be adequately supported throughout their lengths.
2) No air-conditioning ducts shall pass thought fire walls unless as provided for in by-laws
148 and 156.
3) The air intake of any air-conditioning apparatus shall be situated such that air shall not
be recirculated from any space in which objectionable quantities of inflammable vapors
or dust are given off and shall be so situated as to minimise the drawing in of any
combustible material.
UBBL SECTION 162– Fire Doors in compartment walls and separating walls
1) Fire doors of the appropriate FRP shall be provided
2) Openings in compartment walls and separating walls shall be protected by a fire door
having a FRP in accordance with the requirements for that wall specified in Ninth
Schedule to these By-laws
3) Openings in protecting structures shall be protected by fire doors having FRP of not
less than half the requirement for the surrounding wall specified in Ninth Schedule to
these By- laws but in no case less than half hour.
4) Openings in partitions enclosing a protected corridor or lobby shall be protected by fire
doors having FRP of half-hour.
5) Fire doors including frames shall be constructed to a specification which can be shown
to meet the requirements for the relevant FRP when tested in accordance with section
3 of BS 476:1951
UBBL SECTION 164 – Door closers for fire doors
1) All fire doors shall be fitted with automatic door closers of the hydraulically spring
operated type in the case of swing doors and wire rope and weight in case of sliding
doors.
2) Double doors with rabbeted meeting stiles shall be provided with coordinating device
to ensure that leafs close in the proper sequence.
3) Fire doors may be held open provide the hold open device incorporates a heat actuated
device to release the door. Heat actuated devices shall not be permitted on fire doors
protecting openings to protected corridors or protected staircase.
UBBL SECTIOB 168- Staircases
1) Except as provided for in by-law 194 every upper floor shall have means of egress via
at least two separate staircase
2) Staircase shall be of such width that in the event of any one staircase not being available
for escape purpose the remaining staircase shall accommodate the highest occupancy
load of any one floor discharging into it calculated in accordance with provisions in the
Seventh Schedule to these By-laws
3) The required width of a staircase shall be the clear width between walls but handrails
may be permitted to encroach on this width to a maximum of 75 milimetres.
4) The required width of a staircase shall be maintained throughout its length including at
landings.
5) Doors giving access to staircase shall be so positioned that their swing shall at no point
encroach one the required width of the staircase or landing.
UBBL SECTION 169- Exit Route
No exit route may reduce its width along its path of travel from the storey exit to the final exit.
UBBL SECTION 225 – Detecting and extinguisher fire
1) Every building shall be provided with means of detecting and extinguishing fire and
with fire alarms together with illuminated exit signs in accordance with the
requirements as specified in the Tenth Schedule to these By-laws
2) Every building shall be served by at least one fire hydrant located not more than
91.5metres from the nearest point of fire brigade access.
3) Depending on size and location of the building and provision of access for fire
appliances, additional fire hydrant shall be provided as may be required by the Fire
Authority.
UBBL SECTION 230- Installation and testing of dry rising system
1) Dry rising system shall be provided in every building in which the topmost floor is more
than 18.3 metres but less than 3.05 metres above fire appliance access level.
2) A hose connection shall be provided in each fire-fighting access lobby.
3) Dry risers shall be of minimum “Class C” pipes with fittings and connections of
sufficient strength to withstand 21 bars water pressure.
4) Dry risers shall be tested hydrostatically to withstand not less than 14 bars of pressure
for two hours in the presence of Fire Authority before acceptance.
5) All horizontal runs of dry rising systems shall be pitched at the rate of 63.5 millimetres
in 3.05 metres.
6) The dry riser shall be not less than 102 millimetres in diameter in buildings in which
the highest outlet is 22.875 metres or less above the fire brigade pumping inlet and not
less than 152.4mm diameter where the highest outlet is higher than 22.875 metres above
the pumping inlet.
7) 102 millimetres diameter dry risers shall be equipped with a two-way pumping inlet
and 152.4 millimetres dry risers shall be equipped with a four-way pumping inlet.
UBBL SECTION 243- Fire Lifts
1) In a building where the top occupied floor is over 18.5metres above the fire appliance
access level fire lifts shall be provided.
2) A penthouse occupying not more than 50% of the area of the floor immediately below
shall be exempted from this apartment.
3) The fire lifts shall be located within a separate protected shaft if it opens into a separate
lobby.
4) Fire lifts shall be provided at the rate of one lift in every group of lifts which discharge
into the same protected enclosure or smoke lobby containing the rising main, provided
that the fire lifts are located not more than 61 metres travel distance from the
furthermost point of the floor.
Causes and effects of fire
The causes of fire
In 2013, more than 1 million commercial fires were reported. These fire causes untold amounts
of damage, both financial and emotional, and the hassle of dealing with the ensuing paperwork
and insurance claims cause serious headaches for business owners. There are many reasons
why a fire may break out in a commercial building. Below are the few factors of causing a fire.
Human error
Many fires are caused by simple mistakes which are often not meant maliciously. A coffee pot
that has been accidentally left on or a cigarette butt that wasn’t completely extinguished can
quickly cause a huge fire to break out. The misuse of common equipment is one of the most
common reasons for commercial fires. The best way to prevent them is to ensure that all
employees and visitors are aware of how to properly use all electrical equipment and to provide
designated smoking areas with secure places to extinguish cigarettes.
Arson
Unfortunately, fires that have been deliberately set by people with bad intentions are one of the
leading causes of workplace injuries, damage, and death in commercial building fires. Arson
affects business owners, creates a risk of injury for employees and firefighters, and can result
in job loss for workers. There are many reasons why people may commit arson, including the
desire to collect insurance money, disgruntled employees, and vandalism. An automatic
sprinkler system can help a lot to minimize the damage of commercial fires.
Boilers, furnaces, and water heaters
These pieces of equipment are vital to the functioning of a commercial building, but when they
have been improperly installed or incorrectly maintained, the risk of fire can be great.
Sometimes, these fires are also due to human error such as when combustible materials are
stored too closely to furnaces, boilers, and water heaters. Fire safety plan must be always in
place to help ensure safety in the case of a commercial fire.
Electrical Wiring, Electrical Outlets and Faulty Wiring
Whether it’s in an electrical outlet or a short in the wall, many fires are caused by electrical
wiring. Older homes are the more common cases as they were not wired for the
many appliances that we have filled our homes with. Many homes that were built in the 50′s -
70′s have aluminum wiring that gets very hot and increases the chance of fire.
Improper Storage
Most fires in storage properties are not in warehouses but are in garages, barns, silos, and small
outbuildings. Many fires are started when flammable materials are stored too close to a heat
source.
The Effects of Fire
Building fires, which normally reach temperatures of about 1000 ºC, can affect the loadbearing
capacity of structural bearing elements in a number of ways.
Apart from such obvious effects as charring and spalling, there can be a permanent loss of
strength in the remaining material and thermal expansion may cause damage in parts of the
building which are not directly affected by the fire. All building materials except timber are
likely to show significant loss of strength when heated above 250 ºC, strength that may not
recover after cooling.
1. Timber
Timber browns at about 120 to 150 ºC, blackens around 200 to 250 ºC, and emits
combustible vapors at about 300 ºC. Above a temperature of 400 to 450 ºC (or 300 ºC if a
flame is present), the surface of the timber will ignite and char at a steady rate. Table A-2
shows the rate of charring.
2. Masonry
The physical properties and mechanisms of failure in masonry walls exposed to fire
have never been analysed in detail. Behaviour is influenced by edge conditions and
there is a loss of compressive strength as well as unequal thermal expansion of the two
faces. For solid bricks, resistance to the effects of fire is directly proportional to
thickness. Perforated bricks and hollow clay units are more sensitive to thermal shock.
There can be cracking of the connecting webs and a tendency for the wythes to separate.
In cavity walls, the inner wythes carry the major part of the load. Exterior walls can be
subjected to more severe forces than internal walls by heated and expanding floor slabs.
All types of brick give much better performance if plaster is applied, which improves
insulation and reduces thermal shock.
3. Steel
The yield strength of steel is reduced to about half at 550 ºC. At 1000 ºC, the yield
strength is 10 percent or less. Because of its high thermal conductivity, the temperature
of unprotected internal steelwork normally will vary little from that of the fire.
Structural steelwork is, therefore, usually insulated.
Apart from losing practically all of its load-bearing capacity, unprotected steelwork can
undergo considerable expansion when sufficiently heated. The coefficient of expansion
is 10-5 per degree Celsius. Young’s modulus does not decrease with temperature as
rapidly as does yield strength.
Cold-worked reinforced bars, when heated, may lose their strength more rapidly than
hot-rolled high-yield bars and mild-steel bars. The differences in properties are even
more important after heating. The original yield stress is almost completely recovered
on cooling from a temperature of 500 to 600 ºC for all bars but on cooling from 800 ºC,
it is reduced by 30 percent for cold-worked bars and by 5 percent for hot-rolled bars.
The loss of strength for pre-stressing steels occurs at lower stressing temperatures than
that for reinforcing bars. Cold-drawn and heat-treated steels lose a part of their strength
permanently when heated to temperatures in excess of about 300 ºC and 400 ºC,
respectively.
The creep rate of steel is sensitive to higher temperatures and becomes more significant
for mild steel above 450 ºC, while for pre-stressing steel is above 300 ºC. In fire
resistance tests, the rate of temperature will rises when the steel is fast enough to reach
its critical temperature in order to mask any effects of creep. When there is a long
cooling period, however, as in pre-stressed concrete, subsequent creep may have some
effect in an element that has not reached the critical condition.
4. Concrete
Concrete’s compressive strength varies not only with temperature but also with a
number of other factors, including the rate of heating, the duration of heating, whether
the specimen was loaded or not, the type and size of aggregate, the percentage of cement
paste, and the water/cement ratio. In general, concrete heated by a building fire always
loses some compressive strength and continues to lose it on cooling. However, where
the temperature has not exceeded 300 ºC, most strength eventually will recovered.
Because of the comparatively low thermal diffusivity of concrete (of the order of 1
mm/s), the 300 ºC contour may be at only a small depth below the heated face.
Concrete’s modulus of elasticity also decreases with temperature, although it is
believed that it will recover substantially with time, provided that the coefficient of
thermal expansion of the concrete is on the order of 10-5 per degree Celsius. However,
this varies with aggregate. Creep becomes significant at quite low temperatures, being
of the orders of 10-4 to 10-3 per hour over the temperature range of 250 to 700 ºC, and
can have a beneficial effect in relaxing stresses.
Analysis and Repair
When there is something destroyed, there is always a way to repair them. Below are
some of the ways to analysis and repair the structures when they are destroyed or damaged.
1. Timber
Generally, any wood that is not charred should be considered to have full strength. It may
be possible to show by calculation that a timber section or structural element subjected to fire
still has adequate strength once the char is removed. Where additional strength is required, it
may be possible to add strengthening pieces. Joints that may have opened and metal
connections that may have conducted heat to the interior are points of weakness that should be
carefully examined.
2. Masonry
As with concrete, it is possible to determine the degree of heating of the wall from the color
change of the mortar and bricks. For solid brick walls without undue distortion, the portion
beyond the pink or red boundary may be considered serviceable and calculations should be
made accordingly. Perforated and hollow brick walls should be inspected for the effects of
cracks indicating thermal shock. Plastered bricks sometimes suffer little damage and may need
repairs only to the plaster surfaces.
3. Steel
In general, a structural steel member remaining in place with negligible or minor distortions
to the web, flanges, or end connections should be considered satisfactory for further service.
Exceptions are the relatively small number of structures built with cold-worked or tempered
steel, where there may be permanent loss of strength. This may be assessed using estimates of
the maximum temperatures attained or by on-site testing. Where necessary, the steel should be
replaced, although reinforcement with plates may be possible. Microscopy can be used to
determine changes in microstructure. Since this is a specialized field, the services of a
metallurgist are essential.
4. Concrete
In some situations, the replacement of a damaged concrete structural member may be the
most practical and economic solution. Elsewhere, the repair of the member, even if extensive,
will be justified to avoid inconvenience and damage to other structural members. Where new
members are connected to existing ones, monolithic action must be ensured. For repair, the
removal of all loose friable concrete is essential to ensure adequate bonding. Extra
reinforcements should be fastened only by experienced welders. New concrete may be placed
either by casting in forms or by the gummite method. With the latter, it may be possible to
avoid increasing the original dimensions of the member. The choice of method will depend on
the thickness of the new concrete, the surface finish required, the possibility of placing and
compacting the concrete in the forms, and the degree of importance attached to an increase in
the size of the section. Large cracks can be sealed by injecting latex solutions, resins, or
epoxies. Various washes or paints are available to restore the appearance of finely cracked or
crazed surfaces.
Passive and Active Fire Protection
Passive fire protection
Passive Fire Protection (PFP) is an integral component of structural fire protection and
fire safety in a building. PFP attempts to contain fires or slow the spread, through use of fire-
resistant walls, floors, doors etc. We listed down a few examples of passive fire protection
system that can be mostly found in high rise buildings and also their functions.
1. Concrete encasement
Concrete encasement involves pouring of concrete into the formwork to house the steel
members. Reinforcement is provided to hold concrete in place during a fire situation and the
required thickness of the concrete is determined from the design codes. Concrete is used to
encase the steel members because concrete has high fire resistance.
2. Board systems
Board systems are mainly developed using calcium silicate or gypsum plaster. Calcium
silicate boards are made of an inert material that is designed to remain in place during the
duration of the fire. Gypsum boards have good insulating properties as well. Also, its resistance
in fire is enhanced by the presence of water in the board which vaporize in elevated
temperatures. This reaction provides a time delay when the board reaches about 100 °C,
However, it may reduce the strength of the board after exposure to fire.
Calcium silicate board Gypsum board
3. Spray-on protection system
Spray-on protection system is the cheapest form of fire protection for steel members.
Materials used for this method are usually cement-based with some form of glass or cellulosic
fibrous reinforcing to hold the material together. The disadvantages of this method is that the
application is wet and messy and the finished work is not aesthetically attractive. This form of
fire protection is usually applied to beams rather than columns because it can be easily damaged
due to soft material composition. Structural components such as bolts, steel brackets are likely
to be protected with the spray-on protection system because other forms of protection might be
difficult.
4. Intumescent paint
Intumescent paint is a special paint that swells into a thick char when it is exposed to
elevated temperatures to enhance the fire rating of the steel member beneath. The advantages
of this protection system is that the application is a quick process, less bulky and the member
can be simply painted over, thus not deteriorating the appearance of the steelwork.
5. Compartmentation
Compartmentation is basically the division of a building into cells, using construction
materials that will prevent the passage of fire from one cell to another for a period of time. The
most common feature of compartmentation that we all use and see on a day to day basis is a
fire door.
Active Fire Protection
Active Fire Protection (AFP) is an integral part of fire protection. AFP is characterised
by items and/or systems, which requires a certain amount of motion and response in order to
work. The examples and functions of the active fire protections in apartments are as follow:
1. Fire Break Glass Alarm (B.G.A.)
Buildings fitted with a fire break glass alarm allows occupants to activate the fire alarm
and alert the fire brigade easily when there is a fire occurs. The red panel on the wall houses a
small button. It will contact the Fire Brigade when depressed. Thus, Fire Brigade may respond
instantly to the building to reduce the loss caused by fire. The glass or Perspex material of the
fire break glass alarm is easy to break with fist, elbow or a pen. Smashing the glass will
sometimes activate the button automatically.
2. Fire Control System
Most of the apartments are fitted with automatically activated sprinkler heads. On
activation, the sprinklers will discharge a fine mist of water to extinguish or contain the fire. In
other special risk locations such as flammable liquids storerooms or computer rooms, gaseous
flooding systems are used to extinguish fire. Gaseous flooding system is a system that releases
an amount of extinguishing agent adequate enough to flood the closed room. A warning alarm
is sounded prior to the discharge of gas into the room. A warning notice will also instruct the
personnel of what to do.
3. Fire Doors
Fire doors are installed to minimise the spread of fire, including the passage of smoke
through a building. Fire doors may be automatically operated by heat activated mechanisms or
smoke detectors. The person who is leaving the fire area via the fire door must be done so
without the use of keys or similar at all times. Fire doors must also not be wedged open.
4. Smoke and Thermal Fire Detectors
The detection system in buildings may sense either heat or smoke or a combination of
both. Smoke detectors are increasingly being used because of their earlier warning of an
emergency situation. Smoke detectors may also be used to activate fire doors to isolate zones
in the building.
5. Portable Fire Detectors
Portable firefighting equipment such as fire extinguishers are installed to provide the
user with an appliance to extinguish a small fire during its initial stage. Dry powder portable
fire extinguishers are the most commonly used fire extinguishers because it is suitable for all
materials.
6. Fire Hose Reels & Fire Hydrants
Canvas fire hoses attached to or adjacent to fire hydrant points are installed only for use by the
Fire Brigade.
7. Fireman’s elevator
Fireman's elevator operates in two phases; Phase One and Phase Two. In Phase One, activated
smoke detectors or hallway key switches direct elevators to go to a fire recall floor. Upon
reaching the designated landing, passengers are able to exit the elevator and building safely.
The elevators are then removed from normal service. During Phase Two, once the elevator has
reached its designated landing and all passengers are safely evacuated, firefighters can take
exclusive control of the elevator using a special Firefighter’s Service Key switch. This mode
of Fire Service allows firefighters to continue to utilize the elevator to rescue people from other
floors.
Fire Escape Plan for High Rise Building