FEM101 Building Services Revision Notes PDF

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FEM101 Building Services Revision Notes Study Unit 1 Plumbing System Chapter 1 Cold Water Supply 1 2 2 Water Supply from the Authority CP 48: Code of Practices for Water Services Pipe Works Pipe Works Requirements 1) No Interconnection or Potable water supply for drinking and culinary purposes shoul...

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FEM101 Building Services Revision Notes Study Unit 1 – Plumbing System Chapter 1 – Cold Water Supply 1  2 2.1

Water Supply from the Authority CP 48: Code of Practices for Water Services Pipe Works Pipe Works Requirements

 

1) No Interconnection or Cross-connection Potable water supply for drinking and culinary purposes should not be liable to contamination from any less satisfactory water. No inter-connection / cross-connection between pipes containing industrial water / impure water / contaminated water / uncertain quality / water used for other purposes

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2) No Backflow No possibility of backflow towards the source of water supply Valves cannot be relied on to prevent such backflow. Only suitable types of backflow preventors are allowed

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3) Water Tanks Pipe of water tank should be at a height above the top edge of the tank equal to twice its nominal bore, and in no case less than 150 mm

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4) No Contamination of Water Conveyed All pipe work should be completely watertight No piping in any refuse chute / sewer / drain / any manhole connected therewith / ground contaminated by sewage Farmyards, pigsties and the proximity of cesspools should be avoided.

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5) Not to be Used as Earth Electrode Shall not be used as an earth electrode for earthing of an electrical installation. Equi-potential bonding for metallic water pipes shall be carried out by LEW.

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6) No Gas Permeation No using of pipe made of any material susceptible to permeation by any gas or other substance which could cause contamination of the water in the pipe

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2.2

Pipe Work Design Factors: 1) the maximum rate of discharge required 2) suitability of materials 3) ease of installation 4) subsequent maintenance 5) accessibility 6) protection against damage and corrosion 7) avoidance of airlocks 8) noise transmission 9) unsightly arrangement

2.3

Piping Materials Piping and fittings materials shall be: 1) non-corrodible or resistant to corrosion both inside and outside 2) suitably protected against corrosion.

3

Mode of Water Supply

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  

1) Direct Supply Level of highest fitting 125m RL but < 137 m RL Storage capacity = one day's water requirement

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3) Indirect Supply through low level tank with pumping to high level tanks Level of highest fitting > 137m RL Authority’s mains will flow through a meter/master meter to a low level tank Pumps deliver the water to high level tanks-to one day’s water High level storage tanks (compartments) -enable maintenance & cleaning w/o interruption to water supply Inlet to the low level tank between 125 metres and 137 metres RL -storage capacity of the low level tank -1/5 of the daily water requirements (minimum) Inlet to the low level tank is above 137 metres RL -the capacity of the low level tank -at least 1/3 of the daily water requirements.

4

Water Storage

4.1

Water Storage Tank Purpose 1) To provide against interruptions of the supple 2) To reduce the maximum rate of demand on the mains Material 1) Glass Reinforced Polyester (GRP) 2) Stainless Steel 3) Reinforced Concrete Requirements 1) Storage tanks shall be watertight 2) Constructed of non-corrodible or corrosion-resistant material 3) The material shall not impart a taste or odour to the water 4) Shall not have any adverse effect on the quality of the water 5) Where necessary, the storage tanks shall be coated externally with a good quality weather-resisting paint 6) Lead-lined tanks shall not be used 7) Secured against unauthorised access, contamination and pollution of the water 8) Storage tanks shall be fitted with a float-operated valve

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Chapter 2 – Sanitary Plumbing & Drainage System 1

1.1

Sanitary Plumbing & Drainage Systems

Sanitary Piping System 1) To carry away the foul water from the building quickly and quietly 2) Should not create a nuisance or a risk to health, nor damage to the building fabric, but it must prevent air from the drain or sewer from entering the building under all circumstances

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2.1

Types of Sanitary Plumbing Systems

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1) Single Stack System Page 7 of 83

1) Non-Ventilated Stack System 2) For residential buildings up to 6 storey 3) Use where there are single appliances connected to a discharge stack or where the sanitary appliances/ fittings are closely grouped round a discharge stack which is large enough to limit pressure fluctuations without the need for a ventilating stack 4) Permit soil and waste water to discharge into a common pipe 2) Ventilated Stack System 1) For buildings from 7 to 30 storey 2) Close groupings of sanitary appliances around the discharge stack in buildings up to 30 storeys high. 3) The main discharge stack must not be less than 150 mm throughout 4) Separates discharge stack (secondary discharge stack) of diameter not less than loo mm shall be provided to serve the 2nd and 3rd storey. 5) This secondary discharge stack shall be extended to serve as ventilating stack. 6) Cross venting between the ventilating stack and the discharge stack shall be provided at 3rd. 6th. 9th. 12th. 15th.18th. 21st, 24th and 27th storeys. 7) The length of a discharge pipe connecting to the discharge stack shall not be more than 2.5 m and there shall be not more than 2 connections made to the discharge pipe. 3) Fully Ventilated System 1) 2 building arrangements o Up to 6 storey buildings o Building 7 storey or more 2) Discharge pipe serving the 2nd storey shall be connected to a secondary discharge stack of diameter not less than 100mm. 3) This stack shall be extended to serve as ventilating stack but may be reduced to 75mm diameter. 4) Cross venting between the ventilating stack and the discharge stack shall be provided at every 10 storeys

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2.2

Design Criteria for Plumbing System

1) Non- Conveyance of Rain water No sanitary plumbing system shall be used to convey rain water 2) Minimum Pipe work & Adequate Capacity The sanitary plumbing system shall comprise the minimum pipe work and be designed to provide adequate capacity to cater for the discharge from the sanitary appliances to which it is connected. 3) Pipe Sizes The minimum sizes for discharge stacks/pipes and ventilating stacks/pipes to be provided shall be in accordance with the requirements laid down in this Code. 4) Foul Air Exclusion Sanitary plumbing system shall be designed to exclude foul air from the discharge pipes or stacks from entering the buildings. 5) Water Seal Loss In this connection, water seals of sufficient depth (not less than 50 mm) are required to be provided at sanitary appliances and floor traps. Avoid water seal loss in trap arising from pressure fluctuations through the provision of ventilating pipes/stacks or adequate sizing of discharge stacks as appropriate -for the sanitary plumbing system. 6) Venting System Venting system is designed to circulate air throughout the plumbing system to achieve the following 2 goals:  To remove odours and gases from the plumbing system  To Prevent positive or negative pressures from being developed within the plumbing system > will prevent loss of water seals due to induced siphonage and compression 3

Sanitary Drainage System 1) consists of pipes and apparatus that carry sewage from the buildings to the points of discharge or disposal 2) includes drain pipes, inspection chambers and manholes 3) located outside the building and end at the main sewer in the street 4) not connected to surface drainage, because the sanitary discharges must be treated before it is discharged

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3.1

Design Criteria for Drainage System 1) Avoid Causing Nuisance or Danger to Health 2) shall convey only soil and waste from within the premises to the sewerage system. Rainwater shall not be discharged into sanitary drainage system. 3) The size, length and material shall be chosen to facilitate maintenance and reliable service. 4) Bends or kinks are to be avoided in any branch or main drain-line. 5) The branch/main drain-line shall be of the same diameter and laid using the same material throughout its entire length. 6) The branch/main drain-line shall have a constant gradient. The size and gradient of the drain-line shall be chosen to provide adequate carrying capacity and allow for adequate ventilation. 7) Also, the gradient for the branch/main drain-line shall be such as to maintain a sellcleansing velocity of 0.9 m/s and not to exceed a scouring velocity of 2.4 m/s under normal discharge condition.

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Chapter 3 – Gas System 1.1

Difference Between LPG and Town Gas

Liquified Petroleum Gas (LPG)

1.2

Town Gas

Characteristics of Liquefied Petroleum Gas (LPG) The liquid is colourless. It is approximately half the weight of an equivalent volume of water. If LPG is spilled on water, it will float on the surface before vaporising. The liquid occupies about 1/250th of the volume needed if the product was stored as a gas. (It is more practical, therefore, to store and transport the product as a liquid under pressure than as a gas). 5) A leakage of a small quantity of the liquid product a lead to large volumes of vapour / air mixtures and possible hazard.

1) 2) 3) 4)

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Study Unit 2 – Fire Protection System

1

Combustion

1.1

The Fire Tetrahedron 1) 2) 3) 4)

1.2

Flammable Material Oxygen Heat Sustainable Chain Reaction

Extinguishing of Fire 1) Cooling Fire extinguishing by the application of water acts by removing heat from the fuel faster than combustion generates it. 2) Oxygen Starving Application of carbon dioxide is intended primarily to starve the fire of oxygen. Eg. Putting fire blanket to cut off the oxygen supply 3) Remove fuel source A forest fire may be fought by starting smaller fires in advance of the main blaze, to deprive it of fuel. Eg. Physically removing fuel 4) Interference of Chemical Reaction Other gaseous fire suppression agents, such as halon or HFC-227, interfere with the chemical reaction itself.

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2

Fire Hydrants Systems

2.1

Fire Hydrants 1) Fire hydrants should be positioned: within 100m from an entry to any building on the lot and not more than 100m apart. 2) In the case of a building where rising mains are installed: the 100-m distance may be measured up to the breeching inlets of the rising mains

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3

Rising Mains

3.1

Dry Riser (RED) 1) any floor is at a habitable height beyond 24 m and not exceeding 60 m above the ground level 2) For a building under “purpose group" of the Fire Code, having a habitable height exceeding 10 m but not exceeding 60 m

3.2

Wet Riser (YELLOW) 1) any floor exceeding habitable height of 60 m above ground level 2) Wet rising main zone heights exceeding 76m may be permitted when a listed pressure regulating device, which controls nozzle pressure under both flow and no flow conditions, is installed at each outlet 3) In high-rise buildings, the following requirements are also applicable to wet risers:  The maximum zone height shall not exceed 120m  The pressure regulating device is arranged to regulate pressure at the hose valve outlet to a running pressure not exceeding 5.5 bar  The pressure on the inlet side of the pressure regulating device does not exceed the working pressure rating of the device  All other pipe fittings and devices on the system are rated for not less than the maximum system pressure.

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3.3

Rising Mains

3.3.1

No. of Rising Mains

1) All floor not more than 24m above the ground level is within 38m from a landing valve 2) 1 rising main is provided for one or a series of floors higher than 24 m above ground level

3.3.2

Location of Rising Mains and Landing Valves

Within smoke-stop lobby In the common area and within a protected shaft Immediately outside the exit staircase if there is no smoke-stop lobby Inside exit staircase where smoke-stop lobby and common area are not provided Rising mains shall be so located that they are protected against mechanical and fire damage 6) No part of a rising main shall be placed in any shaft containing gas, steam or fuel pipelines or electrical cables and wirings

1) 2) 3) 4) 5)

3.3.3

Size of Rising Mains

1) 100 mm where the rising main does not exceed 45 m in habitable height and only one landing valve is provided at each floor 2) 150 mm where the rising main either:  Exceeds 45 m in habitable height, or  Is permitted to have two landing valves on any floor

3.3.4

Breeching Inlets to Rising Mains

1) Inlets with instantaneous male couplings for connecting to the SCDF's 63.5 mm diameter standard hose shall be fitted to each rising main as follows:  Two-way breeching inlet for a 100 mm bore rising main  Four-way breeching inlet for a 150 mm bore rising main

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3.3.5

Breeching Inlets Locations

1) 2) 3) 4)

Available of fire hydrants The possibility of damage resulting from falling glass from windows, and Other possible occurrences during a fire On an external wall or in a boundary wall of a building and to be within 18m of the adjacent fire appliances access road 5) At street level

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3.4

Flow Requirements for Wet Rising Mains

1) A minimum running pressure of 3.5 bar and a maximum of 5.5 bar shall be maintained at each landing valve when any number, up to 3, are fully opened.

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4

Electrical Fire Alarm System

4.1

Fire Alarm Control Panels Function of Control Panel 1) Control panel is the "brain" of the fire detection and alarm system 2) Responsible for monitoring the various alarm "input" devices such as manual and automatic detection components 3) Activates alarm "output" devices such as horns, bells, warning lights, emergency telephone diallers, and building controls Design 1) Control panels may range from simple units with a single input and output zone, to complex computer driven systems that monitor several buildings over an entire campus. Types of arrangements 1) Conventional (Older technology) 2) Addressable (Newer technology)

4.1.1

Conventional Systems Conventional

1) “Point wired” – Have a dedicated wiring back to the signal processing 2) One or more circuits are routed through the protected space of the building. 3) Along each circuit, one or more detection devices are placed

1) 2) 3) 4)

Factors for Selection & Placement depends on need for automatic or manual initiation ambient temperature & environmental conditions anticipated type of fire desired speed of response

Fire Occurrence Situation 1) One or more detectors will operate. 2) Action will close the circuit, which the fire control panel recognizes as an emergency condition. 3) Panel will then activate one or more signalling circuits to sound building alarms and summon emergency help 4) Panel may also send the signal to another alarm panel so that it can be monitored from a remote point.

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Fault Monitoring 1) To help insure that the system is functioning properly, these systems monitor the condition of each circuit by sending a small current through the wires. 2) Should a fault occur, such as due to a wiring break, this current cannot proceed and is registered as a "trouble" condition. 3) The indication is a need for service somewhere along the respective circuit. Advantages and Disadvantages

4.1.2

Addressable Systems

Addressable Systems 1) State-of-the-art in fire detection and alarm technology. 2) Monitors & controls the capabilities of each alarm initiating and signalling device through microprocessors and system software 3) Major difference -involves the way in which each device is monitored. 4) Each initiating device (automatic detector, manual station, sprinkler water-flow switch, etc.) is given a specific identification or "address".  This address is correspondingly programmed into the control panel's memory with information such as the type of device, its location, and specific response details such as which alarm devices are to be activated.

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Operations 1) The control panel's microprocessor sends a constant interrogation signal over each circuit 2) Each initiating device is contacted to inquire its status (normal or emergency). 3) This active monitoring process occurs in rapid succession, providing system updates every 5 to 10 seconds. 4) The addressable system also monitors the condition of each circuit, identifying any faults which may occur. 5) Therefore, instead of merely showing a fault along a wire, they will indicate the location of the problem. 6) This permits faster diagnosis of the trouble, and allows a quicker repair and return to normal. Advantages & Disadvantages

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4.2

Fire Detectors 1) Fire 2) Heat 3) Smoke / Flame

5

Fire Sprinkler System Provisions 1) Required when compartment requirements of Fire code cannot be complied with 2) All buildings other than purpose groups I & II with habitable height > 24m 3) For mixed occupancy building (residential & non-residential) floors that are >24m, every floor of the non-residential portion shall be sprinklered 4) All basement floors except Groups I & II (residential) shall be sprinklered 5) Basement car parks for Group II buildings shall be sprinklered Exception: When there is only 1 basement and adequate openings are provided for cross ventilation Benefits 1) Immediate identification and control of a developing fire Sprinkler systems respond at all times, including periods of low occupancy. Control is generally instantaneous. 2) Immediate alert In conjunction with the building fire alarm system, automatic sprinkler systems will notify occupants and emergency response personnel of the developing fire. 3) Reduced heat and smoke damage Significantly less heat and smoke will be generated when the fire is extinguished at an early stage. 4) Enhanced life safety Staff, visitors and fire fighters will be subject to less danger when fire growth is checked. 5) Design flexibility Egress route and fire/smoke barrier placement become less restrictive since early fire control minimises demand on these systems. Many fire and building codes will permit design and operations flexibility based on the presence of a fire sprinkler system. 6) Enhanced security A sprinkler controlled fire can reduce demand on security forces by minimising intrusion and theft opportunities. 7) Fires in non-sprinklered buildings Insurance underwriters may offer reduced premiums in sprinkler-protected properties. Page 22 of 83

5.1

Main Components

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5.2

Types of Sprinkler Systems 1) Wet Pipe System 1. Simplest and most common type of installation 2. System is permanently charged with water under pressure up to sprinkler heads 3. Installed where the potential for freezing does not exist 4. Operations: o The wet pipe sprinkler system is charged with water under pressure up to the sprinkler head o When the heat of the fire rises to the sprinkler head’s operating...