BUILDING SERVICES SYSTEMS FOR ELDERLY CARE CENTRE
Building Services BLD 60903/ ARC 2423
Prepared by: Ang Wei Yi
0317885
Chan Yi Qin
0315964
Joyce Wee
0319602
Kan Sook San
0319326
Tan Wing Hoe
0319333
Too Mun Fai
Tutor: Ar. Sateerah Hassan Table of Contents Chapter 1: Introduction to The Building
0318214
Chapter 2: Literature Review 2.1 Fire Protection System 2.1.1 Active Fire Protection System 2.1.2 Passive Fire Protection System 2.2 Air Conditioning System 2.3 Mechanical Ventilation System 2.3.1 Ventilation 2.3.2 Mechanical Ventilation 2.3.3 Comparison Of Supply, Exhaust and Balance system 2.4 Mechanical Transportation System
Chapter 3: Fire Protection System 3.1 Active Fire Protection System 3.1.1 Fire Detection 3.1.2 Fire Alarm System 3.1.3 Fire Control Panel 3.1.4 Fire Intercom System 3.1.5 Fire Hydrant System 3.1.6 Portable Fire Extinguisher 3.2 Passive Fire Protection System 3.2.1 Emergency Fire Escape 3.2.2 Vehicular Access 3.2.3 Fire Barrier 3.2.4 Fire Control
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Chapter 4: Air Conditioning System 4.1 Major Cycles in Air Conditioning System 4.2 Window Unit Air Conditioning System 4.3 Split Unit Air Conditioning System 4.4 Packaged Air Conditioning System 4.5 Central Air Conditioning System 4.6 Proposed Air Conditioning System
Chapter 5: Mechanical Ventilation System 5.1 Types of system 5.1.1 Supply Ventilation 5.1.2 Exhaust Ventilation
Chapter 6: Mechanical Transportation System 6.1 Vertical Transportation System 6.1.1 Elevator 6.2 Hydraulic Elevators 6.3 Roped Hydraulic Elevators
Chapter 7: Conclusion and References
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Chapter 1: Introduction to Building
Site plan
Scale : 1 : 400
In our Design Studio IV, we were required to design and propose an elderly care centre that is no more than 800 square meters in area. The centre also needs to have a specified variety of programs, such as lobby, cafeteria, game room, sewing room and washroom. We had to comply to the standard anthropometry requirements for the elderly and disabled to make sure that they can move around freely and comfortably. Another design requirement is our elderly centre must not use flat roof. For our elderly centre, we tilted the orientation of our main building and also courtyard to face the morning sun and and also to block out the hot afternoon sun on the opposite facade. We attempt to use as much passive design elements to ensure our centre is sustainable and energy efficient, and also to expose the elderly to the natural elements such as the sunlight, wind and fresh air. The service facilities are packed together in the centre of the main block where most of the main programs are located, hence providing a practical and functional circulation for the elderly and staff.
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Chapter 2: Literature Review 2.1 Fire Protection System The purpose of fire protection is to safeguard human lives, preserve material assets and save the environment from devastation. Fire protection system can be categorized into 2 classifications: active fire protection system and passive fire protection system. Active fire protection system is simply the method of fire fighting by using either manual or automatic fire mechanical system such as fire alarms, detectors, hose reels, fire telecoms, sprinklers etc. Passive fire protection system on the other hand retards the combustion and spreading of smoke and at the same time protecting the escape route to prolong the time for evacuation. This system can be done by modifying architectural elements and design with fire resistances characteristics.
2.1.1 Active Fire Protection System Active Fire Protection is a group of systems that require some amount of action or motion in order to work efficiently in the event of a fire. Actions may be manually operated, like a fire extinguisher or automatic, like a sprinkler, but either way they require some amount of action. Active Fire Protection includes fire and smoke alarm systems, sprinkler systems, and fire extinguishers as well as firefighters. Fire and smoke alarm systems are used to detect whether there is fire and smoke in a building. Fire extinguishers and firefighters are used to help put out the fire altogether. These systems are an extremely important part of protecting property and the lives of the people within.
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2.1.2 Passive Fire Protection System Passive fire protection (PFP) is a form of fire safety provision that remains dormant, or inert, during normal conditions but becomes active in a fire situation. It is an integral component of structural fire protection in a building, which is designed to contain fires or slow their spread. The purpose of PFP is to contain the spread of fire for sufficient time to permit i) the safe evacuation of all occupants of the premises and ii) the arrival of the fire brigade. The person responsible for fire safety also has a duty of care towards any members of the emergency services, e.g. fire fighters, who may have to enter the premises during the course of a fire; in slowing the spread of flames, smoke and hot gases, PFP also serves to ensure the building remains as safe as possible for entry in this situation. How is it implemented in buildings? PFP provision is required in all buildings, whether domestic or non-domestic, with the purpose of containing / compartmentalising / retarding the spread of fire. In respect of internal fire spread (structure) â—?
Where reasonably necessary to inhibit the spread of fire within the building, measures shall be taken, to an extent appropriate to the size and intended use of the building, comprising either or both of the following:
â—?
(a)
sub-division of the building with fire-resisting construction;
(b)
installation of suitable automatic fire suppression systems.
The building shall be designed and constructed so that the unseen spread of fire and smoke within concealed spaces in its structure and fabric is inhibited.
Examples of PFP 1. Fire doors, whose purpose is to contain a fire / protect a designated fire escape route, should be fitted with intumescent fire and smoke seals, either around the edges of the door leaf or the frame. These seals are an integral part of a fire door structure and ensure that, not only is the spread of fire prevented, but also and more importantly the ingress of cold smoke in the early stages of a fire. Smoke is known as the silent killer as it can overwhelm the occupants of an enclosed area long before the heat and flames of a fire are sensed. 2. Intumescent air transfer grilles. The hot gases of a blaze can also move swiftly around a building, undetected at first, for example through air conditioning ducts. Air transfer grilles, which are typically 30 or 60 minute fire rated, allow air to circulate freely around a building under normal conditions, but the intumescent material swells and creates a barrier to restrict the passage of hot gases in a fire situation. They are suitable for use with both fire rated doors and compartment walls. 3. Intumescent pipe wraps and collars are designed for use on plastic pipes that pass through masonry floors and walls; the intumescent material expands inwards in a fire situation to squeeze the collapsing pipe until the opening is completely sealed.
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4. Intumescent downlighter covers and fire hoods / canopies for recessed light fittings prevent fire from penetrating the ceiling void and thus preserve the fire resistant integrity of the ceiling; they are typically 30 or 60 minutes fire rated. 5. Intumescent socket box. Electrical sockets in walls and skirting boards are another vulnerable point in a fire rated compartment; intumescent socket box inserts / covers expand to fill the electrical box in a fire, preventing the spread of flames, smoke and hot gases. 6. Testing and certification When choosing PFP products, it is important to ensure that they have been tested to the relevant and current British standard: for example, BS476: 1987 (Fire tests on building materials and structures) Part 20 (Method for determination of the fire resistance of elements of construction – general principles) and Part 22 (Methods for determination of the fire resistance of non-loadbearing elements of construction).
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2.2 Air Conditioning System Malaysia has a tropical rainforest climate which being hot and humid throughout the year. Due the moderate outdoor air quality caused by the industrial development, it has affected the indoor air quality as well. Thus, thermal comfort is one of the significant factors that affect the building design. Thermal comfort is defined as the condition of mind that expresses satisfaction with the thermal environment and is assessed by the subjective evaluation. The application of air conditioning system in Malaysia is needed to achieve the optimal air temperature, air humidity and air cleanliness for the occupants. Air conditioning system produces cool ventilation inside the building in which the heat is taken out from the surroundings to allow the release of chilled air. Its function is to: ●
Adjust the air temperature and air humidity to maintain the human comfort level
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Filter and remove the air microorganisms, dust and soot effectively
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To lower the internal heat gain from electrical appliances and occupants
There are four types of air conditioning system that are commonly used for different applications. ●
Window unit air conditioning system
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Split unit air conditioning system
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Packaged unit air conditioning system
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Centralized air conditioning system
The choice of which air conditioner system to use depends upon a number of factors including the size of the area is to be cooled and the total heat generated inside the enclosed area. From the analysis of the designed elderly care centre, variable refrigerant flow with master and slave system from split unit air conditioning system is the most appropriate and effective way to ensure the thermal comfort level for the occupants in medium scale building that is located in a residential area.
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2.3 Mechanical Ventilation System Mechanical ventilation can be found in various systems according to the function of the space. There are three type of system, which are supply ventilation system, exhaust ventilation system and balanced ventilation system. 2.3.1 Ventilation Natural Ventilation ●
Natural ventilation is the process of supplying and removing air through an indoor space by natural means, meaning without the use of a fan or other mechanical system.
●
It uses outdoor air flow caused by pressure differences between the building and its surrounding to provide ventilation and space cooling.
Mechanical Ventilation ●
A building ventilation system that uses powered fans or blowers to provide fresh air to rooms when the natural forces of air pressure and gravity are not enough to circulate air through a building.
●
Mechanical ventilation is used to control indoor air quality, excess humidity, odours, and contaminants can often be controlled via dilution or replacement with outside air. However, in humid climates specialised ventilation systems can remove excess moisture from the air.
Figure: Examples of mechanical system (Source: http://energy.gov/energysaver/whole-houseventilation)
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2.3.2 Type of mechanical ventilation system Exhaust Ventilation System Exhaust fans (kitchen, bathroom, and/or whole-house fans) tend to “depressurize� the building, causing infiltration of outside air through any cracks or openings it can find. In the North, where winter is more intense than summer, exhaust-only ventilation may be adequate without inviting damage from moisture. Because summers tend to be short and moderate in cold climates, except for a few days, the building is unlikely to be damaged by occasionally drawing in very hot and humid air through the structure. Conversely, exhaust-only ventilation strategies should not be used in the South. If hot and humid air is drawn into the building for months on end, condensation, mold, and damage are likely to develop.
Figure: Exhaust ventilation air flow diagram (Source: http://energy.gov/energysaver/whole-houseventilation)
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Supply Ventilation System Supply ventilation systems draw clean outside air into the interior living space, usually through a supply vent that feeds into the return duct of a forced air system. Advantages of supply-only ventilation include the ability to control where incoming air is coming from, treat the incoming air, and minimize humid air that is pulled into the living space. Controlled supply also minimizes the potential for combustion appliance backdrafting, a dangerous type of uncontrolled infiltration that is more common in well-sealed and poorly vented basements. Supply-only strategies will “pressurize� the house, which keeps moisture out in hot, humid climates but may cause moisture to condense in walls in cold climates as warm air escapes to the outside. This can be very damaging.
Figure: Supply ventilation air flow diagram (Source: http://energy.gov/energysaver/whole-houseventilation)
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Balanced Ventilation System In a balanced ventilation system (also known as combined ventilation), both the supply air and the exhaust air is done mechanically. The air pressure of the room is in neutral state. As the pressure created by the supply air is then depressurized by the exhaustion of air. This system is known as the most efficient way in ventilating the air as it is independence of outdoor weather despite of noisy environment and high installation cost. The combination of system requires two ducts and fan system. This system usually applied in the area where natural ventilation hardly accesses or hard to control such as basement and suitable for all climates.
Figure: Combined ventilation air flow diagram (Source: http://energy.gov/energysaver/wholehouse-ventilation)
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2.4 Mechanical Transportation System Mechanical transport provides means of raising and lowering people or goods in a building between floors, which used to save time and energy consumption as compared to staircase. There are two kinds of mechanical transportation system, mainly vertical transportation and horizontal transportation. Where common vertical transportation system is elevator and escalator; horizontal transportation system is travelator.
Figure: Vertical Transportation: Elevator (Inside the Building Technology, www.cleantechnotes.org/2013)
Figure: Vertical Transportation: Escalator (Castle Lifts, http://www.castle-lifts.com)
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Figure: Horizontal Transportation: Travelator (Pay Poster, http://payposter.com/poster/travelatorescalator-1327601)
In mid-rise commercial building (4 storeys and above), an elevator must be introduced to ease the usage for disabled people where it is equipped with Braille System. While usage of escalator in shopping malls and airports allows maximum efficiency due to continuous transfer of traffic.
Zoning of lift is presented mostly in high rise building, as it is divided into three section of low, mid, and high; it is categorized into express and local. Such design increases the transfer capacity and lower the waiting time in peak hour. The use of elevator has evolved into a greater subject as it creates better sound insulation, luxurious interior, and lighting.
Horizontal transportation has its restriction to transfer its passenger for merely on the same floor in a lower speed. This type of transportation is used in long spaces or between connecting bridge to decrease energy consumption.
Besides the standard prerequisites in designing a good layout for mechanical transportation, special provisions must be made to enable access for older and disabled people through means only available by utilizing mechanical transportation system. It is also of utmost importance to consider its integration with other services, fire escape, fire protection and meticulous maintenance of the system. This project nevertheless, is a small scaled low-rise building (1-3 storeys), thus of the mechanical transportation systems that the Elderly Care Center employs is the vertical transportation, elevator system.
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Chapter 3: Fire Protection System 3.1 Active Fire Protection System The fire protection system in a building always go through a few stages, which is the detection stage, the notification stage and action-taking stage. When there is a fire in a building, we need early detection in order to prevent further damage to both people and building. The active fire protection system in the building can be thoroughly explained through the fire protection chart flow below.
Figure: Active fire protection chart flow
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Figure: Active fire protection system applied in the building.
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3.1.1 Fire Detection 3.1.1.1 Smoke Detector There are two main types of smoke detectors connected to a fire alarm system; Ionization smoke detectors and Photoelectric smoke detectors. Ionization smoke detectors are best used for sensing fast flaming fires that give off very little smoke. Photoelectric smoke detectors are best used where slow smouldering fires with thicker smoke might occur. A combination of both types of smoke detectors should be installed within a fire alarm system. There are other differing smoke detectors called Multi Criteria smoke detectors. These smoke detectors can have a Photoelectric detector and Heat detector within the same detector. There are also CO2 Detectors which sense for carbon monoxide. There are also other multi criteria detectors which have photo smoke detection, heat detection, infrared detection etc all in the same detector.
Ionization Smoke Detector
Figure: Diagram of Ionization smoke detector in which smoke particles break the circuit. A typical ionization smoke detector typically consists of two plates in close proximity to each other and a radioactive source. Both plates are connected with a battery, which applies voltage to the plates. Consequently, one plate is charged positively (+) and the other one negatively (-). The radioactive source constantly releases alpha particles that knock off the electrons from the surrounding air atoms, thus ionizing the nitrogen and oxygen atoms within the detector chamber. The positively-charged ions are attracted to the negative plate whereas the negatively-charged ions are attracted to the positive plate, thus creating a small, continuous electric current. This small ionization current that can be easily measured by electronic circuitry which is connected to the plates. How do ionisation smoke detectors exactly work in presence of smoke? When smoke molecules enter the ionization chamber, the smoke particles attach to the ions and neutralize them. Consequently, the total number of ionized particles in the chamber is reduced. This reduction yields a Building Services (BLD 60903 / ARC 2423): August 2016
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decrease in the chamber current that is sensed by the electronic circuitry. The drop of current between the plates triggers an alarm. An externally visible red LED lights up when the detector alarm state is energised.
Figure: Example of ionization smoke detector.
UBBL 1984 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 preset time.
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Figure: Indications of the locations of smoke detector.
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3.1.2 Fire Alarm System 3.1.2.1 Alarm Bell Alarm bell is a device that creates loud alert sound. Its functions by means of an electromagnet, consisting of coils of insulated wire wound round iron rods. Once electric is applied, the current will flow through the coils. The rods will then become magnetic and attract a piece of iron attached to a clapper. Once the clapper hits the bell, it will create a repetitive loud ringing sound to alert people.
Figure: Example of alarm bell.
UBBL 1984 Section 237: Fire alarms. 1. Fire alarms shall be provided in accordance with the Tenth Schedule to these By-laws. 2. All premises and buildings with gross floor area excluding car park and storage areas exceeding 9290 square metres or exceeding 30.5 metres in height shall be provided with a two stage alarm system with evacuation (continuous signal) to be given immediately in the affected section of the premises while an alert (intermittent signal) be given in adjoining section. 3. Provision shall be made for the general evacuation of the premises by action of a master control.
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Figure: Indications of the locations of alarm bell.
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3.1.2.2 Manual Call Point Manual Call Points are a manual way of activating a fire alarm system should a fire be noticed. Manual Call Points must be a two action device to activate and to stop unwanted activations. First you need to break the cover glass or plastic and then activate the switch. Once activated the fire alarm can only be reset at the FAP. Returning the switch to its normal location will not reset the fire alarm system.
Figure: Example of manual call point.
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Figure: Indications of the locations of manual call points.
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3.1.3 Fire Control Panel A fire control panel is a component that offers control through a fire alarm or notification system. Throughout the building, sensors are installed. These sensors redirect information to this control panel. They include environmental changes that could detect the presence of a fire. The panel receives notifications for potential operational issues with equipment that could cause a fire.
Figure: Example of fire control panel.
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Figure: Indications of the locations of fire control panel. 3.1.4 Fire Intercom System Building Services (BLD 60903 / ARC 2423): August 2016
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Fire intercom system is a two-way emergency voice communication system. It provides communication between remote telephone handsets located within the building and the master telephone hand-set at the fire command center. When the Fire Intercom System receives a call, the alert lamp will flash at the Master Control Panel and an audible signal can also be heard. To turn off the audible signal, simply lift the Remote Handset. There is also a Fault Indicator Unit, which is used to indicate the type of fault from the Master Control Panel. When the master control console has no incoming call, there will be an outgoing call straight to the fire station. Fire station will have to contact the fire command center immediately to contact to the management office. The fire intercom system is mostly placed at the staircase so that in any case of emergency, immediate alert can be sent to the master console. Occupants do not have to run all the way to the security room to announce the emergency.
Figure: Example of fire intercom system.
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Figure: Indications of the locations of fire intercom system.
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3.1.5 Fire Hydrant System 3.1.5.1 Dry Riser System Description
Figure: Diagram of typical arrangement for dry riser system. Dry risers are a type of internal hydrant for the fireman to use. They are used only if the topmost floor of the building is higher than 18.3m and less than 30.5m above the fire appliance access level. Breeching inlets are used to connect the firemen pump water, so that water can provided at ground level and are connected to the bottom of the dry risers. Dry risers are usually dry and depend on the fire engine to pump water into the system through the breeching inlet outside the building. If fire happened, fire engine has to connect the pipe into the dry riser inlet. Hence, the inlet should not locate more than 18m from fire appliance access and not more than 30m from the nearest fire hydrant. There is no pump built internally within the premise, the pressure is totally depend on the fire engine from ground floor.
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Design Requirements 1. Design Standards a. Part 1- Hydrant systems, hose reels and foam inlets b. Part 2- Landing valves for dry risers c.
Part 3- Inlet breeching for riser inlets
d. Part 4- Boxes for landing valves for dry risers
2. Landing Valve a. Provided in each floor and comply with landing valve for dry risers. b. Located at fire access lobbies, protected staircases and protected lobbies. c.
Installed not more than 0.75m above floor level.
d. To protect landing valves, box are provided. e. Fire hose not less 38mm diameter, 30m length, 60mm diameter and nozzle should be provided.
3. Breeching Inlet a. Fire brigade breeching inlet installed at bottom of riser should comply with inlet breeching. b. Breeching inlets enclosed within a box and labeled ‘Dry Riser Inlet’. c.
Drain should be provided at bottom of riser to drain the system after use.
d. Two-way breeching inlet should provided 100mm diameter dry riser. e. Four-way breeching inlet installed with 150mm diameter dry riser. f.
Breeching inlets should located not more than 18m from appliance access road and not more 30m from near external hydrant outlet.
3. Riser Pipe a. Riser pipe diameter located within fire access lobby or staircase at 150m if highest outlet more than 22.875m above breeching inlet or otherwise pipe riser diameter is 100mm. b. Riser pipe will galvanised iron to heavy gauze or class c tested to 21 bar. c.
Horizontal runs pipework feeding the risers should slope to enable proper draining.
d. Air release valve should installed at top of riser to relieve air trapped. e. Riser pipe should electrically earthed or connected to building earth to avoid equipotential.
UBBL 1984 Section 230: Installation and testing of dry rising system. 1. Dry rising systems shall be provided in every building in which the topmost floor is more than 18.3 metres but less than 30.5 metres above fire appliances access level. 2. A hose connection shall be provided in each fire fighting access lobby. Building Services (BLD 60903 / ARC 2423): August 2016
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Figure: Indications of the locations of dry riser and breeching outlets.
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3.1.5.2 Hose Reel System Description
Figure: Diagram of typical arrangement for hose reel system. Hose reel system is intended for the occupant to use during the early stages of fire and comprises hose reel pumps, fire water tank, hose reels, pipe work and valves. The hose reel system generally serves as an initial fire fighting aid. When the hose reel is brought into use the pressure in the pipe immediately downstream of the pump check valves will drops below the field adjusted pressure setting of the pressure switch thereby triggering the pump to comes into operation automatically to feed a steady supply of water to discharge through the hose. Fire fighting hose reel is the part which can be easily accessible. The fire hose reel outlets should be properly housed in glass fronted cabinet secured under lock and key.
Design Requirements 1. Design Standards e. B.S. 5306: Part 1 or the equivalent Malaysian Standard f.
M.S. 1447: Hose reels with semi-rigid hose
g. Pr EN 694 : Semi-rigid hose for first aid fixed installation 2. Hose Reels a. Coverage range of 30m for each reel. b. One hose reel for every 800 sq.m space area. c.
Usually located along escape routes or beside exit doors or staircases.
d. Minimum discharge by each hose reel 30 l/m and 6m jet length. e. The rubber hoses should be comply with pr EN 694 standard and 30m in length and 25mm diameter.
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f.
Nozzles should be of the jet and spray adjustable type of different diameters but 8mm is a recommended size.
g. Pipework is generally 50mm diameter and the pipe feed to individual hose not less than 25mm diameter. h. Above ground pipework : minimum galvanised steel medium grade (Class B). i.
Underground pipework : minimum heavy grade (Class C).
j.
Pipe painted with primer & finished with red paint (OR at least elbow and tee must be painted with red bands).
UBBL 1984 Section 244 (b): Hydraulic Hose Reels Hose reel shall be located at every 45 meters (depends on building form). Besides, fire hose reel should be located at strategic places in buildings, especially nearer to fire fighting access lobbies in order to provide a reasonably accessible and controlled supply of water for fire extinguishing.
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Figure: Indications of the locations of hose reel cabinets.
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3.1.6. Portable Fire Extinguisher
Figure: Diagram of different types of fire extinguisher. 3.1.6.1 Dry Chemical Dry chemical fire extinguishers extinguish the fire primarily by interrupting the chemical reaction of the fire triangle. Today's most widely used type of fire extinguisher is the multipurpose dry chemical that is effective on Class A, B, and C fires. This agent also works by creating a barrier between the oxygen element and the fuel element on Class A fires. Ordinary dry chemical is for Class B & C fires only. Using the incorrect agent can allow the fire to re-ignite after apparently being extinguished successfully.
Figure: Example of dry chemical portable fire extinguisher. UBBL Section 227: Portable extinguishers. Portable extinguisher shall be provided in accordance with the relevant codes of practice and shall be sited in prominent positions on exit routes to be visible from all directions and similar extinguishers in a building shall be of the same method of operation.
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Figure: Indications of the locations of portable fire extinguishers.
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3.2 Passive Fire Protection System
Passive Fire Protection is the use of fire barrier systems that are integrated into the structure of a building. Passive fire protection system plays a very crucial role in preventing/ slowing down the rate of spread of fire and protecting the occupants of the elderly centre in the event of a fire emergency. In this part of the chapter, we will be discussing about the details in the emergency fire escape, fire vehicular access, fire barrier and the fire control that is integrated in the passive fire protection system in the elderly centre.
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3.2.1 Emergency Fire Escape 3.2.1.1 Emergency Exit Signage The emergency exit signs are exit indications for the occupants of the elderly centre during fire evacuation. The exit signs are located above all exits, fire rated doors, fire staircases and doorways that leads the occupants out of the building. Per UBBL and Malaysian Standards, fire escape doors must be indicated with neon green “EXIT” signs (“KELUAR” as in Bahasa Melayu) above it, accompanied with emergency lights. In the event when the electrical supply is cut off when the fire alarms are triggered, the emergency exit signs will still be visible to lead the occupants to safety.
Figure: Example of ‘Keluar” sign
Figure: Indications of the locations of emergency exit signs.
UBBL 1984, Section 172: Emergency Exit Signs.
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1. Storey exits and access to such exits shall be marked by readily visible signs and shall not be obscured by any decorations, furnishings or other equipment. 2. A sign reading “KELUAR” with an arrow indicating the direction shall be placed in every location where the direction of travel to reach the nearest exit is not immediately apparent 3. Every exit sign shall have the word “KELUAR” in plainly legible letters not less than 150 millimetres high with the principal strokes of the letters not less than 18 millimetres wide. 4. All exit sign shall be illuminated continuously during periods of occupancy. 5. Illuminated signs shall be provided with two electric lamps of not less than 15W each.
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3.2.1.2 Fire Evacuation Route One of the most crucial aspects in passive fire protection is the design of the building. The elderly centre consists of 2 L-shaped blocks that forms an open courtyard in the middle. The 3m setback that surrounds the building is clear from obstructions to allow an escape path for the occupants in events of an emergency. At every level, there is a minimum of 2 storey exits to allow the occupants to escape from one if the other is blocked from hazards or fire. The evacuation routes of the building are protected by fire walls and doors to slow down the spreading of flame. They are also equipped with emergency lights and vents to allow safe travel to the open space at the ground level.
Figure: Indicates the fire evacuation routes.
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UBBL 1984, Section 165 (4): Measurement of travel distance to exits. The maximum travel distance to exits and dead end limits shall be as specified in the Seventh Schedule of these By-Laws. UBBL 1984, Section 169: Exit Route. No exit route may reduce in width along its path of travel from the storey exit to the final exit. UBBL 1984, Section 178: Exits for institutional and other places of assembly In buildings classified as institutional or places of assembly, exits to streets or large open space, together with staircases, corridors and passages leading to such exits shall be located, separated or protected as to avoid any undue danger to the occupants of the place of assembly from fire originating in the other occupancy or smoke therefrom.
Conforming to the UBBL, 1. All exits are directed to the open spaces at the side of the building that leads to the assembly point. 2. The passageway is protected from fire and smoke. 3. The width of the escape path is consistent throughout the escape route to prevent clogging of human traffic during evacuation.
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3.2.1.3 Fire Stairs and Fire Lifts Fire stairs and lifts are vertical escape component of the evacuation route. It should be easily accessible from the inside and outside of the building. It is designed for emergency escapes while also allowing firemen to enter the building in an event of fire. In the elderly centre, there is a minimum of one fire stair in each building. The fire stairs are either at the exterior of the building or are well ventilated with vents. The fire stairs are all built with reinforced concrete covered with anti-slip ceramic tiles.
Figure: Indicates the location of fire lifts and stairs
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UBBL 1984, Section 165: Exits to be accessible at all times. Except as permitted by-law 167 not less than TWO separate exits shall be provided from each storey together with such additional exits may be necessary. UBBL 1984, Section 168: Staircases 1. Except as provided in bylaws 194, every floor shall have means of egress via at least 2 separate staircases. 2. Staircases should be at such width that in the event of any one staircase not being available for escape purpose the remaining staircases 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 staircase shall be clear width between walls but handrails may be permitted to encroach on this width to a maximum of 75 millimetres. 4. The required width of staircase should be maintained throughout its length including at landings. 5. Doors giving access to staircases shall be so positioned that their swing shall at no point encroach on the required width of the staircase or landing.
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3.2.1.4 Assembly Point In passive fire protection system, all emergency escape routes must lead the occupants of the building to the outdoor assembly point. Due to the small scale of the elderly centre, there is only one assembly point, which is at the setback area away from the building.
Figure: Indications of the Assembly Point UBBL 1984, Section 178: Exits for institutional and other places of assembly In buildings classified as institutional or places of assembly, exits to streets or large open space, together with staircases, corridors and passages leading to such exits shall be located, separated or protected as to avoid any undue danger to the occupants of the place of assembly from fire originating in the other occupancy or smoke therefrom.
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3.2.1.5 Emergency Light During a fire, all electric supply will be cut of to prevent the risk of an explosion. The emergency lights function automatically in the event of a power failure. It is fitted with charged battery to illuminate the fire escape routes. The level of illumination, quality and consistency of emergency illumination are important during the evacuation of occupants.
Figure: Indications of the locations of Emergency Lightings
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3.2.1.6 Emergency Escape Plan Emergency Escape Plans are located at every fire escape doors. The plan indicates the fire lifts to prevent the occupants from using and being trapped in the regular lift in the event of a fire. The plan is highlighted with red and yellow to indicate the exit stairs and escape area respectively. Information such as the location of the manual breaking glass, fire alarm bells and fire extinguishers are also indicated on the emergency escape plan.
Figure: Emergency Escape Plan.
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3.2.2 Fire Fighting Access 3.2.2.1 Vehicular Access Fire vehicle access around the building is very important as well in order for the fire trucks to get in place especially to the location nearby the fire hydrant for firefighting and rescue activities without any obstructions. The access must be wide enough and clear from any blockages to enable high reach appliances, such as the turntable ladders and hydraulic platforms, to be used and also to enable the pumping appliances to supply water and equipment for firefighting. In the elderly centre, the fire rescue trucks stops at the drop off area as it is unable to enter further into the bungalow lot. Fire fighters will enter the compound through the setback area at both sides of the building.
Figure: Indication of Vehicular Route. UBBL 1984 Section 225 (2): Detecting and extinguishing fire. Every building shall be served by at least one fire hydrant located not more than 91.5m away from the nearest point of fire brigade access.
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3.2.3 Fire Barrier 3.2.3.1 Fire Wall Fire wall is a lightweight; non-loadbearing walls capable of providing up to 240 minutes’ fire resistance. They are an assembly of materials that not only act as a wall to separate the spaces but also separate those high fire risk areas such as transformer room, electrical room and mechanical room. This firewalls were designed to act as a barrier between spaces and prevent the spread of fire in a period of time and give more time for occupants to escape from the building. It buys sufficient times for the occupant and the users to escape.
Figure: Indications of the Fire Walls
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UBBL 1984, Section 138(C) Any wall or floor separating part of a building form any other part of the same building, which is used or intended to be used mainly for a purpose failing within a different purpose group as, set out in the Fifth Schedule to these by laws.
UBBL 1984, Section 148(6): Special requirements as to compartment walls and compartment floors. Any compartment walls or compartment floor which is required by these Bylaws to have FRP of one hour or more shall be constructed wholly of non-combustible materials and, apart from any ceiling, the required FRP of wall or floor shall be obtained without assistance from any noncombustible materials.
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3.2.3.2 Fire Door Fire resistant doors are used to separate compartments in buildings to stop the spreading of fire. It suppresses the fire by restricting the flow of oxygen and spread of flames. The fire doors are placed at the entrance of fire staircase and are self closing to protect the occupants while evacuating in case of an emergency. The elderly centre is equipped with double leaf doors of 1600mm x 2100mm for the escape doors and single leaf doors of 900mm x 2100mm for the mechanical and electrical services room. The fire doors are all rated to withstand up to 1 hour of fire, allowing ample time for fire personnel to put out the flame before it spreads.The doors are closed by default with an hydraulic spring installed at the top of the door to inhibit flame and smoke. Routine checks are made to make sure there is no blockage at the door.
Figure: Indications of the locations of Fire Doors
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UBBL 1984, Section 162: Fire doors in compartment walls and separating walls. 1. Fire doors of an 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 the Ninth Schedule to these bylaws. 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 the Ninth Schedule to these bylaws but in no case less than half an 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 BS476:1951.
UBBL 1984, Section 164 (1): Door closers for fire doors. All fire doors shall be fitted with automatic door closed of the hydraulically spring operated type in the case of swing doors and of wire rope and weight type in the case of sliding door.
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3.2.3.3 Separation of Fire Risk Area Compartmentalization or also known as separation of fire risk areas are implemented in buildings with high fire risk facilities. In the elderly centre, there are N rooms with high risk of causing a fire - kitchen, mechanical and electrical room. These rooms are separated with fire wall and doors to retard the spreading of fire from the rooms. These areas are the most fire protected and maintenance checkups are scheduled every fortnight to ensure all systems are in order.
Figure: Indications Separated Areas: Kitchen and Mechanical and Electrical Rooms. UBBL 1984, Section 139: Separation of fire risk areas. The following areas or uses shall be separated from the other areas of occupancy in which they are located by fire resisting construction of the elements of structure of a FRP to be determined by the local authority based on the degree of fire hazard: (a)
Boiler rooms and associated fuel storage areas
(b)
Laundries
(c)
Repair shops involving hazardous processes and materials
(d) Storage areas of materials in quantities deemed hazardous (e)
Liquefied petroleum gas storage areas
(f)
Linen rooms
(g)
Transformer rooms and substations
3.2.4 Fire Control
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3.2.4.1 Smoke and Heat Ventilation According to statistics, victims of fire often die from smoke and heat stroke. Fire produces black smoke which suffocates the victims due to the lack of oxygen in the air. Therefore it is important to vent out the smoke and heat. Fire stairs are one of the areas that are less likely to be affected by the fire but the smoke from other floors are likely to travel up through the stairwell. Assuming the stairs are in an enclosed area, the smoke will accumulate at a space with the highest human occupancy during a fire, risking the lives of the occupants. To resolve this issue, stairs are either designed to be at the exterior, or to have vents to allow ventilation. The vents can also be removed by fire personnel for access to upper floors in case of huge fire.
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Chapter 4: Air Conditioning System Air Conditioning system is to provide cool ventilation by altering the properties of air which is primarily temperature and humidity to more favourable condition. The control of temperature and humidity in air may be desirable to maintain the thermal comfort level of the occupants and to meet the requirements of industrial processes the external climatic conditions. The main concept of the air conditioning system is to extract the heat from a certain area to the surroundings. It requires several mechanical components to allow the process of evaporation, compression and condensation of the air properties. 4.1 Major Cycles in Air Conditioning System 4.1.1 Refrigerant Cycle Refrigerant cycle is a process to transfer heat from low temperature to high temperature. The heat inside a room is transferred through the evaporator and removed to the outside air through a condenser. 4.1.1.1 Principles of Refrigeration
Figure: Process of Refrigeration Source: (Hoffman & Content, 2002)
The main principle of refrigeration: -
Liquids absorb heat when changed from liquid to gas
-
Gases give off heat when changed from gas to liquid.
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4.1.1.2 Components of Refrigeration Compressor The compressor is the heart of the system. The compressor pumps the refrigerant through the air conditioning system at a designed flow rate and pressure.
Source: (Ebazar, 2016)
Condenser The high pressure and high temperature state of the vapor refrigerant is then converted to liquid at the cond.
Source: (“Mitsubishi Lancer A/C Condenser,� n.d.)
Expansion valve
Control the flow of the liquid refrigerant to evaporator. This is a dividing point between the high pressure and low pressure sides of the system.
Source: (Pony, 2016)
Evaporator It removes heat from air, water or other substance. It acts as a heat exchanger that transfers heat from the substance being cooled to a boiling temperature.
Source: (Asia, 2006)
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4.1.2 Air Cycle A process of distribution of treated air into a certain area that needs to be conditioned. The treated air is the air supply to the area is filtered through air cleaner to remove dust particles. Latent heat inside the room is eliminated and transferred to the medium at the Air Handling Unit (AHU). The medium to absorb the heat can be either air or water. Distribution of air can be either through ducts or chilled water pipes. Heat inside the room is removed and the internal air becomes cooler with the mix of fresh air from outside. 4.1.2.1 Components Required for Air Cycle Air Handling Unit (AHU) It is used to re-condition and circulate air as part of a heating, cooling, humidifying, dehumidifying, filtering and distributing. It uses a blower to remove air from the home, force it through a heat exchanger and distribute the conditioned air through a system of ducts back into the house.
Source: (“Air handling unit BASIC - AHU airtecnics,” 2012)
Air filter
Remove the dust particles in the air before it releases into the room.
Source: (Home, 2015)
Blower fan Propeller fan is used especially to remove heat from the condenser. Its function is to to propel the air for distribution inside the building.
Source: (“DIDW Blower Fan,” n.d.)
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Ductwork and diffuser
Both are to distribute the air from air handling units to the other rooms that need to be conditioned. The ductwork is usually concealed inside the ceiling. The diffuser is placed where the air to be released.
Source: (“Ductwork ventilation from air conditioning UK specialists: RAC Kettering provide air conditioning, cold rooms and refrigeration,� n.d.)
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4.2 Window Unit Air Conditioning System Window air conditioner is the most commonly used air conditioner for single rooms. In this air conditioner all the components, namely the compressor, condenser, expansion valve or coil, evaporator and cooling coil are enclosed in a single box. This unit is fitted in a slot made in the wall of the room, or more commonly a window sill. The whole assembly of the window air conditioner can be divided into two compartments: the room side, which is also the cooling side and the outdoor side from where the heat absorbed by the room air is liberated to the atmosphere.
Figure: Components of Window air conditioner Source: (“Parts of the window air conditioners,” 2009)
4.2.1 Refrigeration System of Window Unit Air Conditioner The refrigeration system comprises of all the cycle.
of the window air conditioner important parts of the refrigeration
Source: (“Parts of the Window Air Conditioners: Part One”, 2016)
The compressor used in the window air conditioners is hermetically sealed type, which is portable one. The condenser is made up of copper tubing and it is cooled by the atmospheric air. It is covered with the fins to enable faster heat transfer rate from it. The capillary tubing made up of various rounds of the copper coil is used as the expansion valve in the window air conditioners. Before the capillary, there is a drier filter that filters the refrigerant and also removes the moisture particles, if present in the refrigerant.
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The evaporator is also made up of copper tubing of number of turns and is covered with the fins. The evaporator is also called as the cooling coil since the rooms air passes over it and gets cooled. Before the evaporator, there is a air filter fitted in the front panel or front grill. As the room air is absorbed, it is first passed over the filter so that it gets filtered. The filtered air is then blown over the cooling coil and the chilled air is passed into the room. The refrigerant after leaving the cooling coil enters the accumulator where it is accumulated and then it is again sucked by the compressor for recirculation over the whole cycle.
4.2.2 Air Circulation System of Window Unit Air Conditioner The air circulation system of the window air conditioner comprises of blower, condenser fan and fan motor.
Figure: Components of Air Circulation System of Window Unit Air Conditioner Source: (“Parts of the window air conditioners,� 2009)
4.2.2.1 Components required Blower: The blower sucks the air from the room which first passes over the air filter and gets filtered. The air then passes over the cooling coil and gets chilled. The blower then blows this filtered and chilled air, which passes through the supply air compartment inside the window air conditioner assembly. This air is then delivered into the room from the supply air grill of the front panel. Condenser fan: The condenser fan is the forced draft type of propeller fan that sucks the atmospheric air and blows it over the condenser. The hot refrigerant inside the condenser gives up the heat to the atmospheric air and its temperature reduces. Fan motor: It has double shaft on one side of which the blower is fitted and on the other side the condenser fan is fitted. This makes the whole assembly of the blower, the condenser fan and the motor highly compact.
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4.2.3 Control System of Window Unit Air Conditioner There is control panel or the operating panel that carries various control buttons. This control panel can be easily accessed from the front panel of the window air conditioner. The three important aspects that are to be controlled inside the window air conditioner: -
Thermostat for controlling the room air temperature Air flow rate inside the room Direction of the air flow inside the room
Figure: Components of Control System of Window Unit Air Conditioner Source: (“Parts of the window air conditioners,� 2009)
4.2.4 Advantages and Disadvantages of Window Unit Air Conditioning System Advantages -
Suitable for small unit Low noise output and high efficiency It does not contribute to distribution of smoke in occurrence of fire Can be placed either in windows or wall holes for easy installation
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Disadvantages -
-
Requires a large hole in the wall if it is not installed at existing window opening More of a hassle to remove and move to another room/location Maybe look unattractive from the outside
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4.3 Split Unit Air Conditioning System Split air conditioner consists of two parts that are the outdoor unit and the indoor unit. The outdoor unit is fitted outside the room such as houses components like the compressor, condenser and expansion valve. The indoor unit comprises the evaporator or cooling coil and the cooling fan. 4.3.1 Components Required for Split Unit Air Conditioning System Outdoor unit Huge amount of heat is generated inside the compressor and the condenser of the outdoor units. Therefore, there should be sufficient air flows around it. The outdoor unit contains the important parts of the split air conditioner like compressor, condenser and expansion valve.
Source: (“Cleaning split AC,” 2015)
Indoor unit
Source: (“FolksERA,” 2016)
Wall mounted indoor unit
Source: (M, 2015)
Source:(sobatcara, 2015)
Floor mounted indoor unit
Cassette
The indoor unit produces the cooling effect inside the room. It is a box type housing in which all the important parts of the air conditioner are enclosed. The most common type of the indoor unit is the wall mounted type though other types like ceiling mounted and floor mounted are also used.
Copper Tubing
The refrigerant piping is made up of copper tubing covered with insulation that connects the indoor and the outdoor unit. It consist of two pipes, one to supply the refrigerant to the cooling coil and the other to return the refrigerant to the compressor.
Source: (“Shanghai tatsukin hvac epuipment co.,ltd,” n.d.)
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4.3.2 Types of Split Unit Air Conditioning System -
Split unit without outside air (ductless)
-
Split unit with outside air (ducted)
-
Variable refrigerant flow (VRF)
4.3.2.1 Split Unit Without Outside Air (ductless) There are no supply of fresh air to renew the existing indoor air. Thus, the existing indoor air is recycled and recirculated.
Figure: Process of Working Ductless Split Unit Air Conditioning System Source: (“Toronto air conditioning | HVAC experts,” 2015)
4.3.2.2 Split Unit With Outside Air (ducted) Ducting piping is used to deliver conditioned air into each room. The ducting pipes are usually concealed in ceiling. It has larger capacity as compared to ductless system.
Source:(“Concealed Ducted split system,” 2016)
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4.3.2.3 Variable refrigerant flow (VRF) Variable refrigerant flow is a multi split air conditioning system where one outdoor unit is connected to several indoor units. It uses refrigerant as the cooling medium. The term variable refrigerant flow refers to the ability of the system to control the amount of refrigerant flowing to the multiple evaporators (indoor units), enabling the use of many evaporators of differing capacities and configurations connected to a single condensing unit. The arrangement provides an individualized comfort control.
Source:(Bachao, 2012)
Types of variable refrigerant flow (VRF) -
Master and slave system Zoned control units Variable refrigerant volume system
Master and Slave System Master unit can be used to control the individual unit or all units at the same time while slave unit control itself only. It is suitable for single areas, single rooms or even multiple rooms with very similar heat gain. Zoned Control Units Each indoor unit has its own individual temperature controller and each unit functions as required to maintain the individual room temperature. Variable refrigerant volume system It is able to provide total versatility and each indoor unit may cool / heat independently of each other.
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4.3.4 Advantages and Disadvantages of Split Unit Air Conditioning System Advantages -
Low initial cost and low noise Ease of installation Each system is totally independent and has its own control of temperature
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Disadvantages -
Maintenance (cleaning/change of filters) is within the occupied space Limited air throw which can lead to possible hot or cold spots Impact on building aesthetics of large building if too many outdoor units will spoil the appearance of the building.
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4.4 Packaged Air Conditioning System Packaged air conditioning system is a larger version of the window air conditioner. Unlike window air conditioning system, it has a higher cooling capacity and it is usually able to cool an entire house or a commercial building. The nominal capacities ranges from 3 tonne to 15 tonne. There are two possible arrangements with the package unit. In the first one, all the components, namely the compressor, condenser, expansion valve and evaporator are housed in a single box. The cooled air is thrown by the high capacity blower, and it flows through the ducts laid through various rooms. In the second arrangement, the compressor and condenser are housed in one casing. The compressed gas passes through individual units, comprised of the expansion valve and cooling coil, located in various rooms. Two types of packaged air conditioning system: -
Packaged Air Conditioners with Water Cooled Condenser
-
Packaged Air Conditioners with Air Cooled Condenser
4.4.1 Packaged Air Conditioners with Water Cooled Condenser The condenser is cooled by the water. The condenser is of shell and tube type, with refrigerant flowing along the tube side and the cooling water flowing along the shell side. The water has to be supplied continuously in these systems to maintain functioning of the air conditioning system.
Figure: Components of Packaged Air Conditioners with Water Cooled Condenser Source: (“What is packaged air conditioner? Types of Packged air Condtioners,� 2010)
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4.4.2 Packaged Air Conditioners with Water Cooled Condenser The condenser of the refrigeration system is cooled by the atmospheric air. There is an outdoor unit that comprises of the important components like the compressor, condenser and in some cases the expansion valve. The outdoor unit can be kept on the terrace or any other open place where the free flow of the atmospheric air is available. The fan located inside this unit sucks the outside air and blows it over the condenser coil cooling it in the process. The cooling unit comprising of the expansion valve, evaporator, the air handling blower and the filter are located on the floor or hanged to the ceiling. The ducts coming from the cooling unit are connected to the various rooms that are to be cooled.
Figure: Components of Packaged Air Conditioners with Water Cooled Condenser (Left) Figure: Location of Diffuser in Packaged Air Conditioners with Water Cooled Condenser (Right)
Source: (“What is packaged air conditioner? Types of Packaged air Conditioners,� 2010)
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4.5 Central Air Conditioning System The central air conditioning plants or the systems are used when large buildings, hotels, theatres, airports, shopping malls etc. are to be air conditioned completely. There is a plant room where large compressor, condenser, thermostatic expansion valve and the evaporator are kept in the large plant room. They perform all the functions as usual similar to a typical refrigeration system. However, all these parts are larger in size and have higher capacities. The compressor is of open reciprocating type with multiple cylinders and is cooled by the water just like the automobile engine. The chilled is passed via the ducts to all the rooms, halls and other spaces that are to be air conditioned. Thus in all the rooms there is only the duct passing the chilled air and there are no individual cooling coils, and other parts of the refrigeration system in the rooms. The amount of chilled air that is needed in the room can be controlled by the openings depending on the total heat load inside the room. Two Types of Central Air Conditioning System -
Direct Expansion (DX) Type of Central Air Conditioning System
-
Chilled Water Central Air Conditioning System
4.5.1 Direct Expansion (DX) Type of Central Air Conditioning System The air used for cooling space is directly chilled by the refrigerant in the cooling coil of the air handling unit. Since the air is cooled directly by the refrigerant the cooling efficiency of the DX plants is higher. However, it is not always feasible to carry the refrigerant piping to the large distances hence, direct expansion or the DX type of central air conditioning system is usually used for cooling the small buildings or the rooms on the single floor.
Figure: Components of Direct Expansion (DX) Type of Central Air Conditioning System
Source: (“Direct expansion (DX) type of central air conditioning plant or system,� 2009)
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4.5.1 Chilled Water Central Air Conditioning Systems The ordinary water or brine solution is chilled to very low temperatures of about 6 to 8 degree Celsius by the refrigeration plant. This chilled water is pumped to various floors of the building and its different parts. In each of these parts the air handling units are installed, which comprise of the cooling coil, blower and the ducts. The chilled water flows through the cooling coil. The blower absorbs return air from the air conditioned rooms that are to be cooled via the ducts. This air passes over the cooling coil and gets cooled and is then passed to the air conditioned space.
Figure: Components of Chilled Water Central Air Conditioning Systems Source: (“Chilled water central air conditioning plants,� 2009)
4.5.2 Advantages and Disadvantages of Central Air Conditioning System
Advantage -
Filter air prevents potentially harmful gases
Disadvantage -
-
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Higher energy bill Frequent duct maintenance Ductwork installation is a major renovation that involves opening up walls and floors Unable to control temperature individually
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4.6 Proposed Air Conditioning System Split Unit Air Conditioning System Variable Refrigerant Flow (VRF) with Master and Slave System Justification The building design is in a clustered form as there are several rooms that connected and clustered together. The second floor is an open space, therefore, air conditioning system is not needed on the second floor. VRF is a multi-split air conditioning system that one outdoor unit connects to several indoor units, therefore, it can reduce the amount of outdoor units that affect the aesthetic of the building. The aesthetic of the building may be affected if too many ductless split unit air conditioners are used because the outdoor units are located right outside of the wall where it is near to the indoor unit. In addition, low noise output which is suitable for elderly that need a quiet environment in the elderly care centre. The ease of installation and maintenance that is appropriate for medium scale centre. Furthermore, master unit can be used to control the individual unit or all units at the same time while slave unit control itself only. It is suitable for single areas, single rooms or even multiple rooms with very similar heat gain.
The Location of Outdoor Units Outdoor Unit: The outdoor unit is located in the open space on the terrace so that the air can flow freely over the compressor and the condenser. The location of outdoor unit that it is easily accessible for carrying out the maintenance works of the compressor, condenser, and other devices. The installation and gas charging also should be convenient. There are any hindrances in front of the outdoor that would block the passage of fan air from passing to the open space. Any blockages will seriously affect the performance of the air conditioner and can also lead to the burning of hermetically sealed compressor coil. The outdoor unit is located at the height above the indoor unit.
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Ground floor plan First floor plan
Second floor plan
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Chapter 5: Mechanical Ventilation System Ventilation is a process of exchanging air, includes both replacing air from outside or circulating air within a space. It is important in obtaining healthy and comfort condition. Ventilation helps to prevent heat concentration and air humidity. Mechanical ventilation can thus provide a good air quality condition. Besides, mechanical ventilation is much more controllable compare to the natural ventilation. Relying on airflow via openings through walls, windows or roof, there’s no control of the source and the amount of airflow. The elderly home is a residential building of 3 floors consist of kitchen, living space, meditation, rest room‌ tbc 5.1 Type of Mechanical Ventilation System Applied 5.1.1 Supply Ventilation 5.1.2 Exhaust Ventilation
Ground Floor Plan
First Floor Plan
Figure: Indications of the locations of supply and exhaust ventilation.
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5.1.1 Supply Ventilation â—?
Supply Air Diffuser/ Grille/ Fan Its the supply ventilation system applied at which central fans are installed to a building to
bring in the external air and supply fresh air through air grille into an internal space.
5.1.1.1 Component Of Supply Ventilation
Ceiling Fan A ceiling fan is a mechanical fan, serves the purpose of removing hot, humid, polluted air. It’s often used to bring in external air into internal spaces to cool down the building temperature. One of the major supply ventilation system in mechanical ventilation, it help to keep the fresh air circulating within the internal spaces.
Wall Mount Fan Installed in exterior walls and pull air directly outside. These fans do not need ductwork, but might have a visible register. Apply at the exterior of corridor to provide air ventilation during mid day.
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Supply Air Diffuser/ Grille A diffuser is "a device for reducing the velocity and increasing the static pressure of a fluid passing through a system�. Diffusers are used to slow the fluid's velocity while increasing its static pressure. The fluid's static pressure rise as it passes through a duct is commonly referred to as pressure recovery.
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5.1.2 Exhaust Ventilation â—?
Exhaust Air Grille/ Fan
Its the exhaust ventilation system applied at spaces which are installed to a building to vacuum internal air through air grille to an external space.
5.1.2.1 Component Of Exhaust Ventilation
Range-Hood Exhaust Fan The fan draws the air into the hood, through the grease duct, through the air purifier (if present), and discharges the air out of the building to the outdoors. Kitchen Exhaust is always discharged outdoors; it is never recycled back into the building.
Ceiling Mounted Exhaust Fan Toilet exhaust systems remove harmful fumes and unpleasant odors from the bathroom. A clean toilet exhaust system will ensure a comfortable climate within an enclosed area.
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Chimney Style These fans work essentially like a self-contained hood except that they have a decorative chimneylike extension that conceals the exhaust duct above the collector. Fans can be just above the hood or installed some distance away, minimizing noise. Chimney-style hoods can be mounted on a wall or over a cook surface in a kitchen island.
UBBL: MS 1525 code 8.4.5 Mechanical Ventilation Control “Each mechanical ventilation system (supply/exhaust) should be equipped with a readily accessible switch or other means for shut down or volume reduction when ventilation is not required. Example of such devices would include timer switch control, thermostat control, duty cycle programming and CO/CO2 sensor control�
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Chapter 6: Mechanical Transportation System Mechanical transportation system is an integral part of modern buildings, used to move goods and people vertically or horizontally between floors. Common types of transportation system such as lifts, elevators help to reduce energy and save a lot of time. 6.1 Vertical Transportation System Vertical transportation systems include all kinds of transportation media within buildings, such as elevators, escalators, hydraulic hoists, and passengers conveyors etc. It may be considered the most important building services system for high-rise buildings. 6.1.1 Elevator An elevator is a type of vertical transport equipment that efficiently moves people or goods between floors (levels, decks) of a building, vessel or other structures. Elevators are generally powered by electric motors that either drive traction cables or counterweight systems like a hoist, or pump hydraulic fluid to raise a cylindrical piston like a jack.
According to UBBL 1984 clause 124, a lift shall be used for non-residential buildings that exceed 4 stories above or below main entrance. It is also essential in buildings less than 4 storeys if access for older or disabled people is considered. It is introduced to bring convenience to the users by allowing them to access varies levels which saves time and energy.
The quality of elevator performance is determined by a few factors: ●
The hoisting capacity
●
Waiting interval
●
Acceleration rate of the car
●
Speed of the lift
●
Time taken for passengers to enter and leave the lift
There are, in general, two major categories of elevators, namely electric elevators and hydraulic elevators. For this project, the Elderly Care Center, hydraulic elevator is chosen and applied in the building.
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6.2 Hydraulic Elevators Buildings up to about (1 to 3) storeys typically use hydraulic elevators because of their lower initial cost. The conventional hydraulic elevator car is raised and lowered by means of a movable rod rigidly fixed to the bottom of the car. The absence of cables, drums, traction motors, elaborate controllers, safety devices, and penthouse equipment makes this system inherently inexpensive and often the indicated choice for low-speed (up to 1m/s), low rise (up to 20m) applications, where construction of the plunger pit does not present difficulties, and/or the absence of a penthouse is desirable. The components of a typical hydraulic unit are shown in Figure 6.2.
Figure: Phantom view of a conventional “holed� hydraulic elevator. (Source: http://www.skodtecelevators.com/hydraulic-elevator.php)
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Characteristics of Hydraulic Elevator ●
Used for low-rise applications of 2-8 storeys
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Travel at a maximum speed of 61m per minute
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The machine room is located at the lowest level adjacent to the elevator shaft
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Suitable for goods lifting, lifts for hospital and old folk’s home
Benefits of Hydraulic Elevator Noise ●
Noise source can be placed in the machine room far away from the shaft
Design and space ●
Smaller space requirement in the shaft
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Flexible machine room location
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A great deal of design freedom for architects
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No constraints on doorways or the shape of the car
Safety ●
Emergency evacuation procedures are very simple and completely safe
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Much safer when used in earthquake zones
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Safety during service and repair work, since there is no moving counterweight
Maintenance and service ●
Low-maintenance drive technology
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No wear on pulleys and ropes
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Replacement parts are seldom needed
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Free choice of maintenance companies
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Drive is easy accessible
Installation ●
Simple and economical assembly
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Hydraulic elevators are particularly suitable for projects where retrofitting is involved
Costs ●
More cost effectiveness
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Operation is simple - lower maintenance cost
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The load imposed is lower compared to electric traction lift - reduce structural cost
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6.3 Roped Hydraulic Elevators Where drilling a plunger hole present difficulties, a hydraulic installation using a roping arrangement can be used. The roped hydraulic arrangement is fairly simple because it uses only a single moving jack section, compared to two or even three in a telescoping unit for the same rise. It accomplishes this by using 2:1 roping, which means that the car travels twice as far as the piston. This is accomplished by passing the rope over a pulley in the piston crosshead. One end of the rope is attached to a fixed point in the pit below the car, and the other end is attached to the base of the car (Figure 6.3). The piston lifts the crosshead, which in turn lifts the car twice as far. The cantilevered car is lifted by cables from the cable crosshead, which is in turn lifted (and lowered) by the single section telescoping piston. The 2:1 roping arrangement lifts the car twice as far as the piston travels. The power unit, which includes the oil tank, pumps, and control, is usually mounted at the lower level. Control is automatic, including automatic leveling.
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Figure: Low-rise residential-type elevator of the roped hydraulic type. (Source: http://www.electricalknowhow.com/2012/04/hydraulic-elevators-basic-components.html) The arrangement shown in Figure 6.3 uses a single jack and a cantilevered car. The simplicity and reliability of the single-jack roped arrangement have made it by far the most common choice for lowrise, light- to medium-duty hydraulic elevators. Because it is a roped unit, it is equipped with a slackrope safety in addition to the other safeties used on direct-connected hydraulic systems.
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Conclusion Complying to the function of the building as an elderly centre, proper considerations were taken when designing the building services for the elderly centre. Considerations such as accessibility, effectiveness, and maintenance were taken into account with reference to the Uniform Building ByLaws (UBBL) to make sure the building complies to the By-Law requirement and is safe to be used over a long period of time. Having elderlies as our main users of the building systems, extra care are given to ensure the safety of the elderlies when using the systems. The conditions of the systems are regularly maintained and patrolled by responsible units to maintain the efficiency and workability of all systems. Conditions of all equipment should be kept up to date and to be replaced when necessary. Through this assignment, we’ve gained basic knowledge of each system and understand the function and significance of each system. Also, we are able to put each system in place according to the requirement and also the needs of the user.
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Inc, B. H. (2008, June 5). Types of air conditioning systems: Window, split, packaged and central. Retrieved November 19, 2016, from http://www.brighthubengineering.com/hvac/897-types-of-airconditioning-systems/ Inc, B. H. (2009, November 8). Installation of the split air conditioners: Deciding the location of indoor and outdoor units. Retrieved November 19, 2016, from http://www.brighthubengineering.com/hvac/45249-indoor-and-outdoor-installation-of-split-airconditioners-deciding-the-location/ Mechanical Ventilation in Buildings – What You Need to Know - TheGreenAge. (2015). TheGreenAge. Retrieved 22 June 2016, from http://www.thegreenage.co.uk/mechanical-ventilation-inbuildings-whatyou-need-to-know/ Natural Ventilation | Sustainability Workshop. (2016). Sustainabilityworkshop.autodesk.com. Retrieved 22 June 2016, from http://sustainabilityworkshop.autodesk.com/buildings/natural-ventilation Osafe Fire Inspection (n.d.). Fire Extinguisher. Retrieved from http://osafefi.com/?ws=pages&pages_id=4228 Passive Fire Protection. (n.d.). Retrieved November 19, 2016, from http://www.firesafe.org.uk/passive-fire-protection/ Patent application (n.d.). Smoke curtain. Retrieved from http://www.patentsencyclopedia.com/app/20090266498 Protec. Wet/Dry Riser Systems. Retrieved from https://www.protec.co.uk/product-page/sprinklers-andwatermist/product/product/wet-dry-riser-systems/ See all Applications. (n.d.). Fire Hydrant Systems. Retrieved from https://www.allpumps.com.au/applications/fire-hydrant-systems Protection. Retrieved Jun 8, 2016, from http://www.sharpfibre.com/blog/5/examining-therelationshipbetween-active-and-passive-fire-protection Spectrumfire. Fire Hose Reel System.Retrieved from http://www.spectrumfire.com/products/firehosereel-system Supply Ventilation. (2016). Greenbuildingadvisor.com. Retrieved 22 June 2016, from http://www.greenbuildingadvisor.com/green-basics/supply-ventilation Supremexfireextiguisher. Fire Extinguisher, A B C Type Dry Powder Fire Extinguisher, CO2 Fire Extinguisher. Retrieved from http://www.supremexfireextinguisher.com/fireextinguisher.html Wormald. (n.d.). Fire Sprinkler Systems, Fire Sprinkler System, Automatic Sprinkler Systems.Retrieved from https://www.wormald.com.au/systems/fire-sprinkler-systems
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