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Basic Design Guidelines for

Mechanical EngineeringSystems

SATURDAY, FEBRUARY 5, 2011

A BASIC DESIGN GUIDELINE FOR MECHANICALENGINEERING SYSTEMS COULD BECATEGORISED INTO FIVE (5) SECTIONS SUCH

AS;

A) SANITARY AND SEWERAGE PIPE MANHOLE SERVICES

x All design guideline for Sanitary and Sewerage Pipe Manhole Services are based on Guide toSewerage Systems - Malaysian Water Association (MWA)/(BS5572:1994)

x Make sure all proposed design calculations and drawings documentation to be preparedearlier and need to be endorsed & sign by the Clients before doing any final BuildingSubmissions to the authorities. (e.g. Majlis Perbandaran Selayang, Majlis Perbandaran Kelang,Majlis Perbandaran Shah Alam, Dewan Bandaraya Kuala Lumpur and etc. Those approvalprocesses would take around three (3) to four (4) months from the date of submission.

B) HOT & COLD WATER PLUMBING SERVICES AND SUCTION & ELEVATED ROOF WATER

TANK & PUMPING SYSTEM

x All proposed design guidelines are based on Guide to Water Supply System JKR/MWAx Make sure all proposed design calculations and drawings for Hot & Water Plumbing and

Suction/Elevated Roof Water Tank and Pumping System need to be prepared for Tender forConstruction purposes and JBA/Syabas and District Council Authorities submission andapproval.

x The Size of Elevated Storage/Domestic Water Tank is based on the number of populationper sq.ft. (100 sq.ft/ 1 person) or Specified Required Gallons of Water Demand per sq.m (2.2Ig/ 1 sq.m) this case would be direct tapping from the Main Bulk Water Meter to theElevated Storage/Domestic Water Tank. Hence, under Penang Water Authorities (PBA) thetotal Water Demand would be around 5.5 Igals/ 1 sq.m.

x In any special case if there is a very low pressure from the Main Bulk Water Meter to theElevated Water Tank, it is required to have One Suction Tank that would be *1/3 ofStorage/day from the total water demand and balance 2/3 of Storage/day is for theElevated Roof/Storage Tank. It is noted that all final selection of Water Tank Size isdepends upon on the incoming size of the pipe from the Water Reticulation (e.g. Size ofDuctile Iron Pipe = 65 mm, need to consider the free board of 10 from the surface ofsitting ball valve to the inner surface of the tank height and the balance bottom heightof 3 where from the height of the water outlets to the inner surface of the bottom watertank.

x A Suction Pump (Booster Multistage Vertical Type) need to be analysed and designed for 6

to 8 hours Operation/day in a proper way by considering all water supply from the SuctionTank to be controlled by On/Off Procedures (Pressure Regulating Control Valves) where couldbe read off by the Motorised Valve at Roof Storage Tanks. The effective capacity (KW) ofthe Suction Pump would be considered by the following criterias:- Design flow rates (Q Igpm) = Total Water Demand / 8 X 60 min.- Total Pump Head (ft.) = Highest Static Head + Pipe Friction Head Loss

(Pipe friction head loss = s.factor, 20% X Pipe friction factor [Equivalent Pipe Length +Straight Pipe Length]

- Min. Pump Cap. = 1.2 X Pump B.H.P X 0.746; i.e. Pump B.H.P = TPH X Q / 3300 X Pumpeffieciency (60% to 65%)

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x The location of the Suction Tank would be at the Ground or Lower Ground Floor dependsupon S.O Architects requirements.

x Material of Suction Tank shall be FRP Fibre Reinforced Plastics or R.C ReinforcedConcrete.

x A Booster Pump for Roof Tanks calculations could be determined by considering the numberand type of fittings to be used and its individual loading units factor. So, by totaling up thenumber of loading units factor then only the required Design Flow Rates (Igmin. ImperialGallon/min.) could be determined by referring to CP310:1965 Graph Fig.1 (Water SupplyRules JKR)

x All Total Pump Head need to be considered by estimating the Total Pump Head (TPH) would

be considered same like determining the Suction Pump.x A Break Tank for Cold Water Plumbing Services only needed as per SYABAS requirement if

the High Rise Apartment/Condominium level height above 75 m.x Below table is a sample plant room & risers that for High Rise Apartment/Condominium that

need to be clarified with S.Os Architects;

Sample Plant Room for Cold water:

Roof tank room 10m x 10m x 4.6m (H) Centre roof area

Roof pump room 4m x 2m x 3m (H) Shall be attached toroof tank room

Suction tank room 10m x 5m x 3.5m (H) Within apartmentfootprint

Suction pump room 4m x 3m x 3.5m (H) Shall be attached tosuction tank room

Cold water riser 1.2m x 0.75m Required nearstaircase 1, 2 & 3

Cold Water Break Tank (if Building height > 75m)(TANK TYPE : FRP)

a) Tank Sizing 4m(W) x 4m(L) x 2m(H) For the buildingheight above 75m.Within 1 no. ofapartment unit forBlock A & B. At Level17th. Sharing withthe apartment unit ofWet Riser break tank.

b) Tank & PumpRoom 4m(W) x 7m(L) x 2m(H)

Swimming Pool Requirement

a) Swimming PoolBalancing TankRoom

6(W) x 5(L) x 5(H) Within apartmentfootprint

(TANK TYPE : RC)

Swimming PoolBalancing TankPump Room

5(W) x 5(L) x 5(H) Shall be attached toswimming poolbalancing tank room

C) AIR

CONDITIONING

& MECHANICALVENTILATION

SERVICES

x All proposed design guidelines are based on HVAC and Air Conditioning System ASHRAE/MASHRAE or SMACNA

x Make sure all proposed design calculations and drawings for Air - Conditioning and MechanicalVentilation System need to be prepared for Tender for Construction purposes.

x The selection of Chiller Unit is firstly to Determine the tentative heat loads for ChillerCondensing unit by doing the estimation on the Average between maximum and minimum ofGrand Total Cooling Load/effective area, Sq.Ft. as can be referred to Table 1 Design andCooling Load Checks (e.g. GTC Hospital = 80 Btuh/Sq.Ft. Factories = 80 Btuh/Sq.Ft., Offices= 75 Btuh/Sq.Ft., Shopping Complexes = 60 Btuh/Sq.Ft. Houses, Condominiums & Apartments= 65 Btuh/Sq.ft. and etc.).

x Then only the Chiller Cooling Load in Btuh Unit need to convert into Ton of Refrigerant - T.R(1 T.R = 12,000 Btuh) and not to forget by adding up the Safety factor of 10 to 15 percent.

x Smoke Control System for the Air Handling Unit for all types of buildings should consider theSuction Air and Return Air. A basic rule of thumbs as referred from below formula;CFM (Suction Air) = RSH (Room Sensible Heat)/1.08 X 15 and CFM (Return Air) = 0.8 GTC

x Cooling Tower Unit need to be determined by adding up 25% (i.e. multiply by factor of 1.25)from the total Chiller Cooling Unit. (T.R unit)

x The Size of Make Up Water Tank need to be determined by considering below formula;Total Size of Cooling Tower (CT-T.R) X 3.0 U.S Gallons X 8 hours of pump operations.(convert to Ig Imperial Gallons, multiply by factor of 0.833)

x Sub total capacity of Chilled Water Flow Rates - for individual AHU Units (m/h) = (GTC,KW)/1.16 X (7C - different of temp. on the refrigerating effects)

x Total Capacity of Chilled Water Flow Rates (m/h) = 7% of Sub total capacity of ChilledWater Flow Rates

x Total Condenser Water Flow Rates (m/h), as at 30C-32C = 25% of Total Chilled WaterFlow Rates(m/h), as at 24C-26C

x Chilled/Condensing Water Pump Capacity = Total Flow Rates,igpm (Condenser/Chiller) X total




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pump head (ft)/3300 X Pump effieciency; considering 1 unit each on standby and 2 units each onduty (total overall = 6 units of Condenser/Chilled Water Pumps)

x Chilled/Condenser Water Pipes could be determined same like the Cold Water PipeCalculations but the only difference is to take care any heat/cold losses from those pipingworks by considering the fire rated pipe insulations.

x Condenser Water flow rates for Water Cool Package Unit (l/min) = (GTC + Input) KW / (7C -different of temp. on the refrigerating effects) X 0.07

x Fan Coil Unit Power Consumption; for Air Cooled Package = 1.5KW/ton and Water CooledPackage = 0.9KW/ton

x Exhaust/Fresh Air Fan for Gen-set and Electrical Switch room; the Air Change/hr (ACH) =

15, Toilet = 10, Kitchen= 20, Basement = 6, Restaurant = 15 to 20 (depends on the heat loadsof the restaurant), Car-park = 12, Lift Motor Room = 12, Auditorium = 0.14 cmm/seat, Canteen= 0.28 cmm/seat and the Air Flow Rates can be calculated, CFM = Room Volume (m) X ACH /60

x Total Pressure Losses for AHU Ducting Lines; Pressure Duct Losses = ( ? ft. X 0.1wg/100ft)+ fan losses = 0.2wg + Grille Losses = 0.1 wg

x AHU Fan Power Rated; Air Flow Rates (m/s) X Total Pressure Losses (mm wg)/102 X motoreffieciency (65%)

x The Air Cooled Supply Velocity from the AHU Air Handling Unit could be determined byusing the Ductulator (e.g. TRANE, YORK DUNHAM BUSH)

x Air Fan Capacity for Kitchen Area (m/hr) = Kitchen Room Size (m) X 25 ACH / 1 hr.x Kitchen Hood Size = W (m) X L (m) X 1.02 (h)x Suction Air Fan at the Kitchen Hood (CFM) = (1.4 X 0.4m/s X 2(W+L) X 1.02, by converting to

CFM) X Grille losses, 0.5wg

D) FIRE PROTECTION SERVICES & FIRE ALARM SYSTEM

x All proposed design calculations and drawings for Fire Protection Services & Fire Alarm

System need to follow a design guidelines that based on the book title; Guide To FireProtection in Malaysia 2nd.edition, March 2006 (Active Submission, by refer to Chapter 5 to13 Portable Fire Extinguisher, External Fire Hydrant System, Hose Reel System, Dry RiserSystem, Wet Riser System, Downcomer System, Automatic Sprinkler System, Automatic CO2Extinguishing System, and Automatic Fire Detection & alarm System)

x Pressurisation System in Building, Smoke Control System Using Natural Displacement orPowered Extracted Ventilation, Fire Lift, and Emergency Power System would be put underseparate submission due to the building requirements (by refer to Chapter 14 to 17)

x All Passive Submission and Performance Base would be under Architectural and C&S Scope ofWorks Only. (Chapter 4 and 18 only)

x Make sure all proposed design calculations and drawings for Active Fire Protection Servicesneed to be prepared for Tender for Construction purposes and BOMBA submission andapproval.

x Portable Fire Extinguisher

It could be categorised into different types of Media and Application/Classes by following itsColour Coding; Water Suit for *Class A fires (in red colour code)

Foam Suit for Class A & B fires (in cream colour code) Dry Chemical Powder Suit for Class A, B, C and E fires (in blue colour code) Carbon Dioxide Suit for Class B & E fires (in black colour code) Halon Suit for Military, Aviation or Special Application (in golden yellow colour code) Wet Chemical System new requirement by BOMBA that need to be installed at all

Kitchen Areas. suit under Class F Selection of the P.F.E Potable Fire Extinguisher; e.g., at the floor area of 1600m:

0.065 X 1600 = 104A104A = 13A X 8 Units of PFE Cylinders X 4 Kg; or108A = 27A X 4 Units of PFE Cylinders X 6 Kg

x External Fire Hydrant System

Design Standard MS1489 Part 1 (Hydrant System, Hose Reels and Foam Inlets)- MS1395 Part 1 (Pillar Hydrant)

Design Method could be categorised into two types of external fire hydrant systems; Direct from main intake to all the pillars Pressurised by Fire Pumps

Pillar Hydrant Location is < 30m from the breeching inlet at the building

Hydrant Pillar System location

6m from the building if it is a High Rise Building Hydrant Pillar Spacing 90m in between and each location has a min. 6m (width) that could

withstand 26 tons. Each Hydrant Pillar should be provided with 30m of 65mm dia. Canvas Hose, Coupling and

Nozzles that to be placed in the special cabinets nearby. In any special case for Pressurised Installation (used Pumps) each Hydrant Pillars (twin

outlets) need to have a Water Supply at the minimum flow rates of 1000 lit./min (1m/h)and at Working Pressure of 4 Bar (58 Psi/9m head/30ft. head).

Each outlets from the Hydrant Pillars 500 lit/min (0.5 m/h) and at min. WorkingPressure of 2 Bar (29 Psi/4.5m head/15ft. head)

Pressure Regulating type of outlet valve need to be introduced if ever the outlet pressurefrom the fire mains boost to 7 Bar (101.5 Psi/16m head/53ft. head)




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Pipe Material of the Hydrant Systems could be categorised into two (2) types thatapproved by BOMBA; Cement Lined Steel Pipe ABS (anti corrosion pipe)

Hydrant Pump Specifications; One (1) Unit Standby 3 m/min (3000 lit./min) Electrical/Diesel Engine driven, One (1) Unit On Duty - 3 m/min (3000 lit./min) Electrical driven and One (1) unit of Jockey Pump To maintain system pressure and as aStart Up for On Duty/Standby Pumps and usually an electrical motor driven with acapacity of around 120 lit./min (0.12 m/min)

The Flow rates for both Standby/On Duty Hydrant Pumps could be increased depends upon the numberof Pillar Hydrants to be installed

because the limitation for the flow rates of 3000 lit/min each pumps are only limited to 3n.o.s of Pillars hydrant only; i.e. 1 n.o.s of Pillar Hydrant = 1000 lit. /min and as example if6 n.o.s of Pillars Hydrant = 6000 lit. /min and so forth.

The Hydrant Pump - Set should be protected from weather (i.e. effect by flooding season) The Fire Water Storage Tank should be sized for a minimum effective capacity of 135,

000 lit. /min (Approximately: 35,000 to 36,000 Imp. Gallons) that would consider theUpper Level height (free board) and bottom level height (600mm/0.6m)

Before doing any testing on the Hydrant Pumps all procedures below need to be followed; Starting the duty pump-set at 80% of the system pressure; Starting the standby pump set at 60% of the system pressure; and Starting and Stopping the jockey pump set at 90% and 110% of the system pressure.

x Hose Reel System

Design Standard

M.S.1489 Part 1: Hydrant System, Hose Reels and Foam Inlets;

M.S.1447 - Hose Reels with semi rigid hose; M.S.1488: Semi rigid hoses for first aid fixed installations.

Design Method of Hose Reel System;

It should be complied with M.S.1447 and stated detailed under the 10 th.Schedule(refer to UBBL)

The location for each hose reel are usually to be placed where could cover 30 metersof hose coverage between the hose reels stack.

Each hose reel outlet to discharge a minimum of 30 lit/min (1.8 m/min) of waterwithin 6 meters of all parts of the space protected.

The rubber hoses should comply to M.S 1488 (min: 30 m in length) Size of Hose Reel Pipe is 50mm (nom. dia.) and the material is Galvanised Steel

Medium Grade Class B for above ground but for Underground G.I Pipe -Heavy GradeClass C & to be feed to individual hose pipe size 25mm dia.

The pipe shall be painted with primer and finished with red paint or may be identifiedwith red bands.

Hose Reel Pumps 1 (One) unit on Duty and 1 (One) unit on Standby Pump Flow Rates 120 lit/min@ operating pressure at 2 to 3 bars (4 Hose Reels could

be activated at one time)

The Standby Hose Reel Pump Set should be supplied with power from the emergencygenerator or diesel engine driven (fuel supply should be adequate for min. 1 hour ofoperation)

Starting and Stopping the Duty pump-set need to be set at 80% and 100% of Systempressure respectively;

Starting and Stopping the Standby pump set need to be set at 60% to 100% ofsystem pressure respectively.

Diesel pump set should be capable of automatic starting but should only be stoppedmanually.

If the total hose reel < 4 Units than no need to use emergency power; i.e ElectricalGenerator or Diesel Engine Driven.

All hose reels system shall not be tapped off from Automatic Sprinkler System Min. Floor Size Area of Hose Reel Stacks : 1200mm - Length X 800mm - Depth (mm) Minimum Effective Capacity of Fire Water Storage Tank should be sized based 2275

litres (500 Ig) for the first hose reel and 1137.5 liters (250 Ig) for every additionalhose reel. The maximum effective capacity is approximately 9100 litres (2001 Ig).

The Material used for the Fire Tank is either made from Pressed Steel (hot dippedgalvanised and coated internally with Bituminous paints for corrosion protection),FRP Fiberglass Reinforced Plastics or R.C Concrete.

This Hose Reel Tank need to be refilled with 50mm Supply pipe and at the min. flowrates of 150lit/min (33 Igpm) Pump Rooms would be located at the Ground Floor or Roof Floor Level and the min. Fire

Protection Plant Room Size as following below table;

Plant Room for Hose Reel Tank

Hose Reel TankRoom

3(W) x 2(L)x 5(H)

Within apartment footprint and couldbe shared with Wet Riser Tank Room if

Required.




5/18

x Dry Riser System

Design Standard

M.S.1489 Part 1: Hydrant System, Hose Reels and Foam Inlets; M.S.1210 Part 2: Landing Valves for Dry Risers; M.S 1210 Part 3: Inlet Breeching Inlet for Risers Inlet M.S 1210 Part 4: Boxes for Landing Valves for Dry Risers

Design Method of Dry Riser System;

It should be complied with UBBL 1984, the by Laws 230 and 232 Dry Risers are a form of internal hydrant and are only required for buildings where

the topmost floor is higher than 18.3 meters and less than 30.5 meters. Dry Risers are basically dry and all depends upon the Fire Engine to pump water into

the system by considering the Breeching Inlet to be located about 30 meters fromthe External Hydrant System.

Landing Valves are provided on each floor and should comply with M.S 1210: Part 2. Those Landing Valves would be located within the fire access lobbies, protected

staircases or other protected lobbies at not more than 0.75 meters from the floorlevel.

To protect the landing valves, boxes may be provided and these should comply withM.S.1210 Part 4.

Fire Hose Reel Pipings > 38mm dia., 30 meters in length, complete with 65mm dia.Quick Coupling and nozzle should be provided at each landing valve.

Breeching Inlet would be installed at the bottom of the riser and should comply withM.S. 1210: Part 3. The breeching inlet is enclosed within a box, the enclosure shouldcomply with M.S.1210 Part 5 and labeled Dry Riser Inlet and a typical drain shouldbe provided at the bottom of the riser to drain the system after used.

2 Way Breeching Inlet should be provided for a 100mm dia. Of dry riser pipes but 4 Way Breeching Inlets : 200mm dia. Of Dry Riser Pipes and should be located 18meters from the fire appliance access road. (the distance of fire fighters truck tobe placed)

The riser pipe diameter size 150mm usually located within the fire access lobby orstaircase if the highest outlet is more than 22.875m above the breeching inlet.Otherwise the riser pipe diameter size 100mm.

The material of the Riser Pipe shall be Galvanised Iron to B.S. 1387 (heavy gauge) orClass C, tested to 21 Bars (305 Psi)

All feeding Pipe-works that runs horizontally need to be sloped to enable properdraining after used and also an Air Release Valve should be installed at the top of

the riser to relief air trapped in the system. The riser pipe should be electrically earthed or connected to the building earth to

achieve equipotential. The riser to be hydraulically tested to a pressure of 14 Bars for 2 hours that to be

measured at the Breeching inlet and not forget to check all leakage at the jointsand landing valves connections.

x Wet Riser System

Design Standard

M.S.1489 Part 1: Hydrant System, Hose Reels and Foam Inlets; M.S.1210 Part 2: Landing Valves for Dry Risers; M.S 1210 Part 3: Inlet Breeching Inlet for Risers Inlet M.S 1210 Part 4: Boxes for Landing Valves for Dry Risers

Design Method of Wet Riser System;

It should be complied with UBBL 1984, the by Laws 231, 232 and 248 Wet Risers are a form of internal hydrant and are always charged with water. The

topmost floor is higher than 30.5 meters and less than 70.15 meters for each stageof Wet Risers. If > than 70.15 meters, so a Break Tank is required.

Wet Riser System comprises duty fire pump with standby pump discharging into a150mm diameter riser pipe with landing valves at each floor and to which canvashose with nozzles can be connected to direct the water jet at the fire.

The function of a Jockey Pump is to maintain system pressure. Landing valves that usually being installed at each floor should comply with M.S. 1210:

Part 1 and located within fire fighting access lobbies, protected staircases or otherprotected lobbies.

The height of the landing valves should be < 0.75 m from the floor level and for thesafety purposes this landing can be protected by providing boxes and need tocomply with M.S 1210: Part 4

Recommended pressure for each landing valve should be in between 4 to 7 bars (58 to

(TANK TYPE : RC) If the location of hose reel tank atroof top than it is advisable to combine

with a Roof Storage Water Tank (i.eShopping Complexes like Carrefour,

Tesco or Giant)Ventilation slots should be provided

with insect screen to prevent entry ofvermin




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102 Psi) Landing Valve could be categorised into two types : -

Pressure reducing type with relief outlet require a wetriser return pipe

Pressure reducing type without relief outlet

Size of the Fire Hose Canvas type 38mm and the required length is 30m. completewith 65mm dia. Of quick coupling and jet and spray nozzle should be provided in ahose cradle beside each landing valve.

Breeching Inlet for the Wet Riser System is normally same with the Dry Riser System

where the firemen could usually pump the water from the water source (ExternalFire Hydrant Pillar located < 30m from the breeching inlet) into the Wet RiserStorage Tank to make up for water used.

These breeching inlets need to be located < 18m from the fire appliance access road.

The Breeching inlet should be a 4 Way type complying with M.S 1210: Part 3 andenclosed within a box that also complies with M.S 1210: Part 5. These boxenclosures need to be labelled as Wet Riser Inlet and to provide a drain at thebottom of the riser to drain the system after use.

Wet Riser Main Pipeline usually located within the Smoke Lobby or protected areasand such that all spaces are to be within 45m coverage from a Landing Valve andmore than one riser is required for each floor.

Distance between the risers should not exceed 60m and also where between thelowest and topmost landing valve in any upper stage risers.

The Size of the Pipe Riser should be 150mm dia. (Galvanised Iron to B.S. 1387 HeavyGauge or Class C)

The Size of Relief Pipe shall be at min. of 100mm dia. (Galvanised Iron to B.S. 1387 Medium Gauge or Class B, where discharging back to the Wet Riser Tank wheneverpossible and all air relief need to be installed at the top of the riser to relief anyair trapped in the system).

The Wet Risers pipe should be coated with primer and finished with red gloss paint orany special condition those wet riser pipes can be colour coded with red bands of100mm width but only at the elbows & tees need to be fully painted in red.

All Wet Riser Pipe should be electrically earthed to achieve equipotential with thebuilding.

There two sets of Wet Riser Pumps One (1) unit is on duty and One (1) unit onstandby and both pump capacity are usually sized to deliver 1500 l/min at a runningpressure in between 4 to 7 Bars that would cater for three (3) landing valves at onetime of operation during building in fire.

All Standby Wet Riser Pump-set should be supplied with power from the emergencygenerator set or otherwise by using a Diesel Engine Driven.

All Fuel Supply should be adequate for minimum 2 hours of continuous mode ofoperations.

Batteries for the Diesel Engine driven type of Standby Pump should maintenance free type.

All electrical cabling to Supply Power the Wet Riser Pumps should be of MICC or FireRated Cable Type.

All Wet Riser Pump Sets should be protected away from fire and flooded areas. A Sump Pump need to be considered for any special case of that Wet Riser Pump

Sets to be located at the basement below the external drainage levels. This WetRiser Pump Sets room also need to be naturally or mechanical ventilated with anecessary signage and to provide a CO2 Portable Type of Fire Extinguisher for anycase of fire.

Effective Capacity of the Wet Riser Tank need to be sized up to minimum capacity of45,500 liters (10,009 Imp. Gallon) c/w automatic refill rate of 455 lit/min (100.1Igpm).

The Intermediate Break Tank for upper stages of the Wet Riser should be sized up toa minimum effective capacity of 11,375 liters (2503 Imp. Gallon) c/w automaticrefill rate of 1365 lit/min (300.3 Igpm).

Wet Riser Tank Materials are usually from a Pressed Steel, Fibre ReinforcedPolyester (FRP) and Reinforced Concrete (R.C)

Pressed Steel Wet Riser Tank should be Hot Dipped Galvanised and CoatedInternally with Bituminous paint for corrosion protection.

Both Pressed Steel and FRP Wet Riser Tank need to be compartmented unless theyare Reinforced Concrete (R.C) and all compartmented wet riser tanks need toprovide with a separate Ball Float Valves, Overflow Pipes, Drain Pipes and WaterLevel Indicator.

All Wet Riser Tank need to be painted red or else a red band of minimum 200mmshould be painted to indicate that this is a fire tank.

All Wet Riser Tank could located on the Ground Floor, 1 st.Lower Ground Floor or

2nd.Lower Ground Floor level. Wet Riser Tanks are usually separated from the Domestic Water Storage/Suction

Tanks but however could be combined with Hose Reel Tank and need to becompartmented.

Pump Starter Panel should be complete with indicator lights as shown at the appendix a.

All types of ventilation slots should be provided with insect screen to prevent entry ofvermin (small insects; i.e. ants, spiders and etc.)

Power Supply cables to the panel should be of mineral insulated copper cable (MICC)




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or fire rated type of cables within areas with low risk. The Fire Pump Starter panel should be placed within the same room as the fire pumps

it controls. Wet Riser Pumps need to be automatically started upon actuation of the pressure

switches but should only be stopped manually. Usually three pressure switches areprovided with the following suggested pressure settings:

starting the duty pump set : 80% of the system pressure starting the standby pump set: 60% of the system

pressure starting and stopping the jockey pump set at 90% and

110% of the system pressure respectively.

Testing requirements for the Wet Riser System are the following; Static Pressure Test to clear up the debris from the inside of Those main wetrisers and hydraulically the

pressure to be tested up to 14 Bars or 150% the WorkingPressure, whichever is the

higher for 2 hours, measured at the lowest landing valveand a check is carried out for

leakage at all joints and landing valve connections..

Flow Test A three way of landing valve should be provided on the roof ortopmost floor for testing purposes

where the main motif is to measure the water flow rates

x Downcomer System

Design Standard

M.S.1489 Part 1: Hydrant System, Hose Reels and Foam Inlets;

M.S.1210 Part 2: Landing Valves for Dry Risers; M.S 1210 Part 3: Inlet Breeching Inlet for Risers Inlet M.S 1210 Part 4: Boxes for Landing Valves for Dry Risers

Design Method of Downcomer System;

It should be complied with UBBL 1984, relating to Downcomer systems is the

10th.Schedule and relevant standards for Downcomer systems as above mentioned. Downcomers are a form of internal hydrant and are only required for buildings where

the topmost floor is not higher than 60 meters above the fire appliance access leveland should be adopted for low cost flats only.

Downcomer system comprises a high level water storage tank discharging into a 150mmdia. Riser pipe with landing valves at each floor and to which canvas hose withnozzles can be connected to direct the water jet at the fire.

No pumps are provided and therefore the system pressure is limited to the staticpressure head only.

Landing Valves are provided on each floor and should comply with M.S 1210: Part 2.

Those Landing Valves would be located within the fire access lobbies, protectedstaircases or other protected lobbies at not more than 0.75 meters from the floorlevel.

A Semi rigid 40mm diameter hose and nozzles should be provided at every landingvalve on each floor.

In addition, two sets of fire hose of the canvas type of not less than 38mm diameter,30 metres in length complete with 65mm dia. quick coupling and jet and spray nozzleshould be provided at the caretakers unit or property management office.

Fire Hose Reel Pipings > 38mm dia., 30 meters in length, complete with 65mm dia.Quick Coupling and nozzle should be provided at each landing valve.

A 4 - Way type of Breeching Inlet would be installed at the bottom of the riser andshould comply with M.S. 1210: Part 3. The breeching inlet is enclosed within a box,the enclosure should comply with M.S.1210 Part 5 and labeled Downcomer Inlet anda typical drain should be provided at the bottom of the riser to drain the systemafter used.

This Breeching inlet should be located at no more than 18 metres from the fireappliance access and not more than 30 metres from the nearest external hydrant.

A Check Valve need to be installed between the topmost landing valve and the tank toprevent any backflow of water from the Downcomer into the tank.

The Downcomer mains are usually located within smoke free lobby or protected areasand that all spaces are to be within 45 metres coverage from a landing valve.

If more than 60 metres, so then need to have more than one riser is required for each

floor. The Riser Pipe size should be 150mm and the material of the Riser Pipe shall be

Galvanised Iron to B.S. 1387 (heavy gauge) or Class C, tested to 21 Bars (305 Psi) All feeding Pipe-works that runs horizontally need to be sloped to enable proper

draining after used and also an Air Release Valve should be installed at the top ofthe riser to relief air trapped in the system.

All Downcomer pipes should be coated with primer and finished with red gloss paint orotherwise can be colour coded with red bands of 100mm width and the elbows andtees painted red.

The riser pipe should be electrically earthed or connected to the building earth toachieve equipotential.

The riser to be hydraulically tested to a pressure of 14 Bars for 2 hours that to be




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measured at the Breeching inlet and not forget to check all leakage at the joints andlanding valves connections.

x Automatic Sprinkler System

Design Standard

BS EN 12845: 2003 Automatic Sprinkler Systems Design, Installation andMaintenance.

NFPA 13Both above standards need to be followed unless the specific aspect is not covered in

the selected standard.

Design Method of Automatic Sprinkler System;

It should be complied with UBBL 1984, the by Laws 226 and 228 An Automatic Sprinkler System is designed for having a response to detect, control

and extinguishes a fire, and warned the occupants of the occurrence of fire.

Basic mechanical installations for the Automatic Sprinkler System are such as likeFire Pumps, Water Storage Tanks, Control Valve Sets, Sprinkler Heads, FlowSwitches, Pressure Switches, Pipe works and valves. This system operatesautomatically without human intervention.

The Sprinkler Head usually has a liquid filled glass bulb that breaks due to heat of thefire and releases water that sprays over the fire.

There are various types of Sprinkler Systems are as follows; Wet Pipe installation ready filled up with water anddischarge once thesprinkler bulb breaks Dry Pipe installation always filled up with air under pressure and air isreleased once the sprinkler bulb breaks then only the water fills the pipe and is discharged at the sprinkler head.

Pre action installation normally charged with air unde pressure and a valve is

opened to fill the system with water when fire is detected by smoke or heat detectors and also when thesprinkler bulb breaks. Deluge Installation the sprinkler head has no bulb and water is dischargedsimultaneously from all heads when fire is detected and the deluge valve is open

Occupancy Hazards Groups;

Light Hazards : Non Industrial occupancies with low quantity andcombustibility contents, e.g. apartments,

schools and hospitals.

Ordinary Hazards : Commercial and Industrial occupancies in which By handlingand storing ordinary combustible materials and group under the followings;

- OH Group I for offices, restaurants and hotels,

- OH Group II for laundries, bakeries and tobacco factory,- OH Group III for car parks, departmental stores, large retail shops and

cinemas, clothing and paint factories and

-

OH Group IIIS for match factories, film and television studios.

1st Noted to Mech. Engr.s : for high rise buildings with multiple type of occupancies,the hazard class recommended is OH Group III

High Hazards : Commercial and Industrial occupancies in which By handling andstoring the abnormal fire

loads covering process hazards, high piled storage hazards, oiland flammable liquid hazards

and group under thefollowings;- Process Risk, e.g. clothing, rubber, wood wool and paint

factories High Piled Storage riskscould be categorised into four (4) categories; Category I

Carpets and textile exceeding 4meters in height, Category II furniture factory piled

- above 3 meters, Category III rubber, wax coated paperpiled > 2m and Category IV for

foam, plastics piled > 1.2m.

Sprinkler Pump Requirements; Normal Standard One (1) unit on Duty, One (1) unit on Standby and One (1) ofJockey Pump

to maintain the system pressure.

The nominal pressure and flow requirements under all types of hazards are asthe followings;

- Light Hazard15 meters: flow - 0.3 m/min and at operating pressure of 1.5 bars30 meters: flow - 0.34 m/min and at operating pressure of 1.8 bars45 meters: flow - 0.375 m/min and at operating pressure of 2.3 bars




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- Ordinary Hazard Group I15 meters: flow 0.9 m/min and at operating pressure of 1.2 bars30 meters: flow 1.15 m/min and at operating pressure of 1.9 bars45 meters: flow 1.36 m/min and at operating pressure of 2.7 bars

- Ordinary Hazard Group II15 meters: flow 1.75 m/min and at operating pressure of 1.4 bars30 meters: flow 2.05 m/min and at operating pressure of 2.0 bars45 meters: flow 2.35 m/min and at operating pressure of 2.6 bars

- Ordinary Hazard Group III15 meters: flow 2.25 m/min and at operating pressure of 1.4 bars30 meters: flow 2.70 m/min and at operating pressure of 2.0 bars45 meters: flow 3.10 m/min and at operating pressure of 2.5 bars

- Ordinary Hazard Group IIIS15 meters: flow 2.65 m/min and at operating pressure of 1.9 bars30 meters: flow 3.05 m/min and at operating pressure of 2.4 bars

2nd. Noted to Mech. Engr.s

for Building exceeds 45m than the multiple stage of sprinkler installationsshould be implemented. This would be able to serve the full height of the buildingwith each stage not exceeding 45 meters.

A standby Sprinkler Pump Set should be supplied with power from theemergency generator or else need to use a diesel engine driven. All Diesel Oil Supplycould withstand 4 hours Ordinary Hazards and 6 hours for High Hazard

applications.

All Electrical Cabling to supply the power to the Sprinkler Pumps should be a firerated cable type or MICC. Batteries for the diesel engine also need to be amaintenance free type

All Sprinkler Pumps that protecting the high rise buildings need to consider thestatic pressure between the pump and the lowest sprinkler head by adding up to theabove pump pressure requirement.

All Sprinkler Pumps should be under positive head as far as possible, protectedfrom fire and flooded areas. Sump Pump could be considered if this Sprinkler Pumpto be located at the Basement below the the external drainage levels. As usual thisPump Room that located at the basement need to be naturally / mechanicalventilatedc/w a necessary signage and must also provide a CO2 Portable Extinguisher.

All Sprinkler Pump Starter Panels and Controls should be Compartmented foreach duty, standby and jockey pumps c/w indicator lights as shown in the figure 11.2

(as per the attachments at apprendix - A

As normal practice all Fire Fighting Pump room need to provide with an insectscreen to prevent entry of vermin (e.g. insects, flies, cockroach and etc.) and thelocation of Pump Starter Panel should be placed at the same room as the fire pumpsit controls.

Usually three pressure switches are provided with the following Suggestedpressure settings:

starting the duty pump set : 80% of the system pressure starting the standby pump set: 60% of the system pressure starting and stopping the jockey pump set at 90% and 110% of thesystem pressure respectively.

Electrical interlocks should be provided so that the sprinkler pumps at eachinstallation would not operate in parallel simultaneously and a buzzer should be sounded and the isolator should bein the off or manual position.

All Sprinkler Pump Sets should be able to start automatically and stop manually.

Sprinkler Fire Tanks

- Light Hazard15 meters: flow - 9 m (1980 Imp. Gallon)30 meters: flow - 10 m (2200 Imp. Gallon)45 meters: flow - 11 m (2420 Imp. Gallon)

Ordinary Hazard Group I15 meters: flow - 55 m (12,100 Imp. Gallon)




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Posted byAbg.Leh at 2:51 AM 9 comments:

30 meters: flow - 70 m (15,400 Imp. Gallon)45 meters: flow - 80 m (17,600 Imp. Gallon)

- Ordinary Hazard Group II15 meters: flow - 105 m (23,100 Imp. Gallon)30 meters: flow - 125 m (27,500 Imp. Gallon)45 meters: flow - 140 m (30,800 Imp. Gallon)

- Ordinary Hazard Group III15 meters: flow - 135 m (29,700 Imp. Gallon)

30 meters: flow - 160 m (35,200 Imp. Gallon)45 meters: flow - 185 m (40,700 Imp. Gallon)

- Ordinary Hazard Group IIIS15 meters: flow - 160 m (35,200 Imp. Gallon)30 meters: flow - 185m (40,700 Imp. Gallon)

- High HazardStorage Capacity shall be dependent on the design density of discharge inmm/min

x It is noted for all Mechanical Engineers to read and understand all other standard &proceedures that required from the

latest Fire Protection Services (Second Edition 2006) at Chapter 11, 12, 13, 14, 15 tillChapter 20.

x Design reference from last and current projects.

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