Dry & Wet Riser Systems

Learning about dry & wet riser system

1. DRY & WET DRY & WET
RISER RISER
SYSTEMSSYSTEMS

2. Who to decide on the nos. of wet riser main/
Dry riser system to be installed ?
•Architect
Where to locate the wet/dry riser ?
•To be decided by Architect

3. Design Criteria
Numbers of rising mains depend on :
•Each rising main serves not more than
930m
2
of floor area
•Cover a distance of 38m from a landing
valve

4. The riser and landing valves shall be housed
in:
• A protected area or lobby or shaft

5. Where to locate the breeching inlet
Design Criteria
Breeching inlet shall be less than 18m from the
fire engine hard standing
Conspicuous position and accessible to the
fireman

6. TYPE OF THE SYSTEMTYPE OF THE SYSTEM
LANDING LANDING
VALVEVALVE
Dry Riser SystemDry Riser System
BREECHING INLETBREECHING INLET
AIR AIR
RELEASEDVALVERELEASEDVALVE

7. Requirement of dry riser installation
•For residential building height more than 45m but
less than 60m, or with basement or commercial
building
•Ø100mm dry riser main pipe is for building
height from 10m to 45m
•Ø150mm dry riser main pipe is for building
height from 45m to 60m

8. Requirement of dry riser installation
•2- way breeching inlet for Ø100mm
rising main
•4- way breeching inlet for Ø 150mm
rising main

9. Breeching Inlet

11. Air Release valve
Hand Wheel
Landing
Valve
Anti-Thief
Device

12. FSSB SUBMISSION IS NOT REQUIRED FSSB SUBMISSION IS NOT REQUIRED
LOCAL AUTHORITIES SUBMISSIONLOCAL AUTHORITIES SUBMISSION
Submission

15. ConventionalConventional
PUMP FEED
GRAVITY FEED
TRANSFER PUMP
WET RISER PUMPS
JOCKEY PUMP
FROM PUB SUPPLY
4 WAY BREECHING
INLET
LANDING VALVE

16. Old designOld design
•Non conventional - phase out
FROM PUB
SUPPLY
AIR
RELEASE
VALVE
LANDING
VALVE
DOMESTIC
FEED
Tanks
WET
RISER
PUMP
4 WAY
BREECHING
INLET
WET RISER TANK

17. Down Comer System Down Comer System
DOMESTIC
21 ST
STOREY
25TH
STOREY
BREECHING
INLET
Ø100mm
GI PIPE
1ST STOREY
Between 60m to 70 m
WET RISER
Phase out for New Building (17
Sep’01)

18. Transfer Water Tank Design
•One rising main = 11.5 m
3
(15min) @ 27 l/s
•Two rising main = 23 m
3
(15min) @ 38 l/s

19. Roof top wet riser tank layoutRoof top wet riser tank layout
DIA 3.62
1m 1m
2m
3m length for pump set
1m
Ring
tanks
3-Rings Tank
3 nos. = 49 m
3

5 nos. =75 m
3
ACOUSTIC
SOUND
INSULATION
3
1
12m
7m
4-Rings Tank
2 nos. = 49 m
3

3 nos. =75 m
3

20. Wet riser tank capacity
•One rising main capacity
= 49 m
3
for half hours + 1.1 m
3
fire hose reel
•Two rising main capacity
=74 m
3
for half hours +1.1 m
3
fire hose reel

21. Building Above 120mBuilding Above 120m
FROM PUB
SUPPLY
1ST STOREY
Mid-Storey
Roof Storey

WET RISER
PUMP
HOSEREEL PUMPTRANSFER PUMP
Down feed
Down feed
Transfer tanks

22. Power required
• PUB supply
• Generator - supply to 4 blocks per generator

23. FSSB SUBMISSION IS REQUIRED FSSB SUBMISSION IS REQUIRED
LOCAL AUTHORITIES SUBMISSIONLOCAL AUTHORITIES SUBMISSION
Submission

25. 50TH STOREY HEIGHT BUILDING50TH STOREY HEIGHT BUILDING

26. WET RISER AND HOSEREEL SERVICE WET RISER AND HOSEREEL SERVICE
DUCTDUCT

27. TESTING AND TESTING AND
COMMISSIONING OF WET COMMISSIONING OF WET
RISERRISER

28. WET RISER REQUIREMENTSWET RISER REQUIREMENTS
RESIDENTIAL COMMERCIAL &
ANY MIXED BUILDING
FLOW RATE 27L/S FOR FIRST 38L/S FOR THE FIRST RISING MAIN
RISING MAIN 19L/S FOR EACH ADDITIONAL
13.5L/S FOR EACH RISING MAIN
ADDITIONAL RISING MAIN MAXIMUM SUPPLY RATE OF 190L/S
MAXIMUM SUPPLY RATE
OF 135 L/S
RUNNING PRESSURE 3.5BAR TO 5.5 BAR 3.5 BAR TO 5.5 BAR
STATIC PRESSURE 8 BAR 8 BAR

29. PLAN VIEW FOR WET RISER AND PLAN VIEW FOR WET RISER AND
HOSE REELHOSE REEL

30. Check
Valve
Gate
Valve
Drain
Cock

31. Check Valve
Rubber Expansion
Joint
Gate
Valve c/w
limit
switch

32. Pilot Valve

33. Motorize
Valve
Pressure
Relief
Valve
Bypass system

34. Flow
Meter

35. Motorize
Valve
Gate
Valve
Down feed

36. Pilot Valve

37. Check
Valve
Flow Switch
Down feed
Pipe

38. Duty Pump
Standby Pump

39. Fire Pump

40. Jockey
Pump

41. Level
Indicator

42. Landing
Valve
Strap Lock

43. Air
Release
valve

44. Drain Cock
Limit
Switch
Butterfly
valve

45. Check
Valve

46. Piping

47. Pressure
Switches
Pressure
Gauge

49. Limit Switch
Indicator Panel
Alarm
Bell
Fire
Extinguisher

50. Wet Riser
Control Panel