Fire protection systems

2
Fire Protection System Design
Strategy
 Comprehensive Strategy
 Prevent fires from starting in the first place
 Education
 Administrative procedures
 Signage
 Inspections
 Fire safety program
 Fire alarm and detection systems
 Detect fires early to initiate quick evacuation
 Design safe egress from building
 Exits, Stairwells, Corridors
 Emergency lighting and ventilation

3
Design Strategies (cont’d)
 Fire suppression systems
 Sprinkler
 Standpipe and Hose
 Chemical
 Smoke Control systems
 Remove smoke from exits
 Provide fleeing occupants with breathable air

4
Design Strategies (cont’d)
 Compartmentalization
 Break a building into small compartments to contain fire and
smoke
 Fire Separation
 Fire rated wall, floor, ceiling assemblies that impede
the spread of fire
 Use of non-combustible materials
 Use of low flame spread and smoke developed
finish material

5
Flame Spread
 ASTM E84 – Test Method for Surface-Burning
Characteristics of Building Materials (Steiner tunnel test).
Rates surface-burning characteristics of building materials
and interior finishes, and provides data on smoke density.
 Flame spread classifications:
 Class A: 0-25
 Class B: 26-75
 Class C: 76-200
 Local building codes generally restrict use of materials in
different occupancies based upon flame spread and smoke
developed ratings.
 For example, NYSED Manual of Planning Standards requires finishes
in corridors, passageways, stairways to be Class A.

6
Sources of Ignition
 Spontaneous Combustion
 Electrical Sources
 Arcing
 Lightning
 Mechanical
 Friction
 Other
 Intentional (arson)
 Cigarettes

7
Fire Issues
 Products of combustion – CO, CO2, other
gases
 Fire quickly consumes oxygen
 Lack of oxygen
 Rapid deterioration of human capabilities
 Muscle control
 Thinking, consciousness, etc.
 Poor visibility

8
Fire Issues (cont’d)
 Vertical shafts promote spread of smoke, heat
 Elevators
 Escalators
 Atriums
 HVAC systems can spread smoke
 Windowless buildings – prevent entry by firefighters
 Interior finishes – can spread fire, give off smoke
 High rise buildings (g.t. six stories) – complicate
firefighting, rescue

9
Fire Alarm and Detection Systems
 Design Standards
 Fire Code of NYS – defines minimum standards where fire alarm and
detection system is required, general design requirements
 NFPA 72 – National Fire Alarm Code – defines specific design
standards
 Functions of a fire alarm and detection system:
 Initiate alarm
 Manually
 Automatically
 Notify occupants
 Audible alarms
 Visual alarms

10
Functions (cont’d)
 Automatically signal fire department or central station
 Recall elevators
 Supervise special systems:
 Fire pump operation, power availability
 Sprinkler system status
 Unlock doors
 Automatically close doors that are part of fire separations
 Automatically release smoke relief hatches
 Control operation of HVAC supply and exhaust fans
 Total shut down
 Special smoke management systems

13
Fire Alarm Systems (cont’d)
 Types
 Conventional (off/on “dumb” devices)
 Addressable
 Analog
 Digital
 Equipment
 Manual Fire Alarm Boxes (Pull Stations)
 Mounting – not less than 3.5 and not more than 4.5 ft above floor
level (ADA requires maximum 48” high forward reach)
 Spacing:
 At exit doorways within 5’ of each exit doorway on each floor; on both
sides of opening 40 feet and wider, and within 5 feet each side
 Additional boxes such that distance of travel to any box less than 200
feet on same floor

14
Manual Alarm Station at Exit

15
Fire Alarm Systems (cont’d)
 Heat Detectors
 Applications
 Where smoke is ordinarily present
 Top of elevator shafts where sprinklers are present
 Types
 Fixed
 Combination fixed/rate of rise
 Location
 On ceiling not less than 4” from sidewall, or on sidewall between
4” and 12” of ceiling

17
Fire Alarm Systems (Cont’d)
 Heat Detectors (cont’d)
 Typical Spacing
 Fixed: 15’x15’
 Combination fixed/rate of rise: 50’x50’
 All points on ceiling within 0.7 x listed spacing
 Special considerations – beam construction,
sloped ceilings – refer to NFPA 72 for spacing
requirements.

18
Smoke From Cooking Appliances Can
Set Off Smoke Detector

19
Stages of a Fire
 Incipient – invisible combustion gases,
without smoke or flame, no appreciable heat
release
 Smoldering – heat still absent, combustion
gases now visible as smoke
 Flame – actual fire is produced, a column of
gases made luminous by intense heat
 Heat – follows concurrently or just after flame
stage – tremendous amounts of heat released

20
Smoke Detectors
 Types
 Spot
 Beam
 Design:
 Ionization
 Photoelectric
 Spot Detector Accessories
 Integral alarm
 Typical use – motels and similar sleeping spaces

21
Photoelectric Spot Smoke Detector
with Integral Alarm
 Photoelectric detectors
operate using principle of
“smoke obscuration”
 Smoke interposed in light
beam between small
emitter and detector
 Decreased light intensity at
detector causes alarm to
sound
 Device in photo also
includes integral alarm –
used in motels and similar
sleeping spaces.

22
Principle of Operation – Ionization
Detector

23
Smoke Detectors (cont’d)
 Applications
 Spot detectors
 For general fire detection
 Close doors, operate smoke dampers
 Beam detectors
 High ceilings where spot detectors impractical
 Location
 On ceiling not less than 4” from sidewall, or on sidewall between
4” and 12” of ceiling

24
Smoke Detector Mounted on Wall

25
Smoke Detectors (cont’d)
 Typical Spacing (spot)
 30’x30’
 All points on ceiling within 0.7 x listed spacing
 g.t. 3’-0” from HVAC diffusers, supply grilles
 Special considerations – beam construction,
sloped ceilings – refer to NFPA 72 for spacing
requirements.

26
Typical “Listed” Smoke Detector
Spacing

27
Incorrect Application of Smoke
Detector
 Area covered = 60’ x
15’ = 900 s.f.
 Distance to corner
exceeds 0.7 x listed
spacing (0.7 x 30 =
21’)
 Two smoke detectors
would be required for
this room.

28
Beam Smoke Detector
 Smoke rising to ceiling will
obscure light beam.
 Receiver will detect change
in beam intensity and cause
alarm to sound.
 Often used in atrium
spaces, high “cathedral
ceilings”, similar spaces.

29
Notification Appliances
 Audible
 Refer to NFPA 72 for sound pressure levels
 Mounting
 Wall – top not less than 90” a.f.f., not less than 6”
below ceiling (where ceiling heights allow)
 If combined with visual appliances, entire lens of
visual appliance not less than 80” nor greater than 96”
a.f.f.
 Spacing
 Such that they can be heard throughout building
 Refer to NFPA 72 for specific requirements

30
Audible Visual Device in School
Cafeteria

31
Audible Visual Fire Alarm Appliance

32
Notification Appliances (cont’d)
 Visual Appliances
 Location
 Wall mounted – entire lens 80” -96” a.f.f.
 Ceiling mounted permitted when device is specifically listed for
this application.
 Spacing
 Refer to NFPA 72
 When two or more in same field of view, must be synchronized
(can be harmful to persons with epilepsy)

33
Remote Annunciator Panel at School
80
 An annunciator panel
displays at remote entries
and other locations the
zone or device that is in
alarm – generally located at
main entries.

35
Types of Fire Suppression Systems
 Standpipe and Hose Systems
A reliable water supply, piping, hose connections to
permit manual extinguishing of a fire.
 Sprinkler Systems
A reliable water supply, piping, sprinklers, to permit
automatic extinguishing of a fire.
 Chemical Extinguishing Systems
Both manual and automatic systems
Use a chemical extinguishing agent where water is not
effective, or cannot be used.

36
Standpipe and Hose Systems
Classification:
Class I – 2-1/2” hose connections for firefighter’s
use, 100 psi at uppermost hose connection.
Class II – 1-1/2” hose connections for occupant use,
100 psi at uppermost hose connection.
Class III – 2-1/2” and 1-1/2” hose connections for
both firefighter’s and occupant use.

37
Diagram of a Typical Standpipe
System

38
Standpipe Hose Valve at Intermediate
Stairwell Landing

39
Typical Backflow Preventer for Fire
Protection Service
 A backflow preventer
prevents water
contained in building
piping systems from
flowing back into the
community water main.
 Water piping in
buildings may contain
foul and/or hazardous
materials.

40
Classification (cont’d)
 Type I and III standpipes are the most
common.
 Design Standard
• NFPA 14 Standard for the Installation of
Standpipe, Private Hydrant, and Hose Systems.
• Current edition is 2003
• As of 2004, NYS Building Code adopts the 2000
edition.

41
Combined Systems
 A combined system is a standpipe that also supplies
automatic sprinklers on each floor.
 Combined systems were first permitted by NFPA in
1976 to encourage owners of high rise buildings that
already had standpipes to install sprinkler systems.
 A sprinkler crossmain is connected to the standpipe
at each floor. A typical connection detail is
contained in NFPA 14 Figure A-5-9.1.3.1 (a) and
(b).

42
Diagram of a Typical Combined
Sprinkler and Standpipe System

43
A Typical Flow Control Assembly
Located in a Stairwell

44
Buildings that Require Standpipe
and Hose Systems
 Buildings where standpipes and hose systems are
required:
 Any building where the highest floor level is 30 ft. or more
above the lowest level of fire department vehicle access.
 Places of Assembly
 Covered Mall Buildings (e.g. Shopping Malls)
 Stages
 Underground Buildings
 Check the applicable building ordinance for specifics
(NYS 905.3)

45
Water Supplies
 Water supply must be among the following:
• Public waterworks with adequate pressure
• Automatic fire pump connected to public
waterworks
• Manually controlled fire pump in combination
with pressure tanks.
• Pressure tanks installed in accordance with NFPA
22

46
Water Supplies (cont’d.)
• Manually controlled fire pumps operated by
remote control devices at each hose station.
• Gravity tanks in accordance with NFPA 22
• Automatic fire pumps connected to the public
waterworks are the most common.

47
Water Supply Capacity
 Water supply capacity
• The capacity of the supply is calculated as
follows:
 500 gpm for the first standpipe
 250 gpm for each additional standpipe
 Not to exceed 1250 gpm
 Water supply must have minimum 30 minutes
duration for calculated flow

48
Additional Classification of Standpipes
 Wet
• The standpipe system is always filled with water.
 Dry
• The standpipe system contains no water.
• Generally used only in unheated buildings (e.g., parking
garages.)
 Automatic
• Water supply capable of supplying system demand
automatically.
• Most common type

49
Additional Classification of Standpipes
(Cont’d)
 Manual
• Connected to small water supply to maintain water in the
system, but inadequate to meet demand.
• Relies on fire department pumper to supply necessary
system demand.
 Other types: semi-automatic dry, manual-dry (see
NFPA 14 for explanations.)
 The Building Ordinance (NYS Building Code)
prescribes which type is required.

50
Fire Pumps
 Fire Pumps
• Since most water main pressures are generally
less than 100 psi at the street, a fire pump is
usually required to provide adequate pressure.
• Fire pumps must be provided with an emergency
power source.
• Fire pumps generally require a separate, fire rated
(2 hr.) room or enclosure.

51
Typical Electric Fire Pump Installation

52
Location of Hose Connections
 Location of Hose Connections
• Height: not less than 3 ft and not more than 5 ft above
floor (usually 4 ft).
 Class I Systems
• In exit stairways at each intermediate landing between
floor levels.
• Each side of wall adjacent to exit openings of horizontal
exits.
• Each exit passageway at entrance from building areas into
passageway.

53
Location of Hose Connections (Cont’d)
 In covered mall buildings at entrance to each exit
passageway or exit corridor, and exterior public
entrances to mall.
 At highest landing of stairways with access to roof,
and on roof where stairways do not access the roof.
 Additional 2-1/2” hose connection at hydraulically
most remote riser to facilitate testing.
 See NFPA 14 for more requirements.

54
Location of Hose Connections
(Cont’d)
 Class II Systems
• 1-1/2” hose stations so that all portions of each
floor level are within 130 ft of a hose connection.
 Class III Systems
• As required for both Class I and Class I Systems

55
Drainage of Standpipes
 Each standpipe to be equipped with a means
for draining
 Usually a drain valve is located at lowest
point of standpipe, downstream of isolation
valve
 Drain to an approved location
• Often drained to spill at grade

56
Fire Department Connections
 At least one fire department connection for
each zone of each Class I and Class III system
 High rise buildings require two remotely
located fire department connections for each
zone
 Height: +18” to +48” above adjoining grade

57
Fire Department Connections (Cont’d)
 A check valve is required downstream.
 No shutoff valve is permitted between the fire
department connection and the system.
 Dry piping between connection and check
valve should be galvanized steel.
 Signage is required at each connection. See
NFPA 14, Ch. 4-3.5.2 for details.

58
Sprinkler Systems
 Definition and purpose – a reliable water supply, piping,
sprinklers, valves and accessories for the purpose of
automatically extinguishing a fire.
 Governing Design Standards
 Local building code or ordinance – prescribes where sprinkler
systems are required
 NFPA 13 Standard for the Installation of Sprinkler Systems –
prescribes how sprinkler systems are to be designed and constructed
 Factory Mutual (FM) – An insurance company standards
organization; it may, through the building owner’s insurance
company, impose additional restrictions/requirements for overall
building fire protection systems.

59
Sprinkler Systems (cont’d)
 Types of sprinkler systems:
 Wet
 Dry
 Pre-action
 Deluge

60
 Wet system
 Piping is filled with water under pressure at all
times.
 When one or more sprinkler heads open, water is
automatically discharged.
 Used in heated buildings or portions of buildings
that are heated.
 Most common type of system.

61
Diagram of a Wet Pipe Sprinkler
System with Water Motor Alarm
 Both pendant and
upright sprinklers may
be used.
 During operation, the
alarm check valve
diverts a small portion
of water to the water
motor alarm – does not
rely on electricity to
sound alarm.

62
A Typical Wet Pipe Sprinkler Alarm
Valve Installation

64
Wet Pipe Sprinkler with Electric
Alarm
 An electric alarm bell is
operated through a water
flow switch inserted into
the main riser.
 When a sprinkler opens,
water flow activates flow
switch, and alarm sounds.
 Requires a reliable source
of power from an
emergency source.

65
Sprinkler systems (cont’d)
 Dry system
 Piping is filled with compressed air.
 A dry system valve blocks the entry of water into the
piping. Air pressure in the piping holds the valve closed.
 When one or more sprinkler heads open
 Air is first released through the head(s)
 Air pressure in the piping system drops.
 Dry system valve swings open.
 Water floods the piping system.
 Used in unheated buildings, or portions of buildings that
are not heated, e.g., attics.

66
Diagram of a Dry Pipe Sprinkler
System
 Upright heads must be
used, in order to allow
the piping to drain
completely.

67
 Pre-action system
 Requires operation of both a fire detector and
a sprinkler head opening before water is
released.
 Piping is filled with pressurized air.
 A fire detection system (smoke, heat detectors, manual
pull station) is wired to the pre-action valve; valve is
opened only when fire detection system is activated.
 Water floods piping.

68
Pre-action system (cont’d)
 Water is released from each sprinkler head that
opens.
 Used for rooms that contain valuable equipment
or materials that could be damaged be release of
water, where fire detection must be verified
independently.
 Main frame computer rooms
 Laboratories

69
Diagram of a Pre-Action System

70
 Deluge System
 All sprinklers are open
 When water fills the piping system, all sprinklers
discharge water simultaneously
 Diagram is similar to pre-action system
 Applications:
 Where severe fire hazard exists that can be
extinguished safely with water
 E.g. – a Fireworks Factory

71
 Where required:
 Governed by the local building code or ordinance
 If not required by code, insurance companies
often offer reduced rates, or won’t insure
buildings without sprinkler systems.

72
Some Sprinkler Types
 Recessed Pendant
Sprinkler
 Glass tube holds metal disc
seated in valve seat
 Glycerin in glass tube
expands when heated and
will shatter glass
 Water is released
 Spray pattern is established
by deflector

73
Recessed Pendant Sprinkler with Brass
Finish

74
Old Style Sprinkler with Fusible Link,
(Upright Style Shown)

75
Sprinkler with Wire Guard and
Deflector Disk (Pendant Style Shown)
 This sprinkler would be
used to protect combustible
materials in storage racks
 Wire guard protects
sprinkler from damage as
racks are loaded/unloaded
 Deflector plate prevents
water may be discharged
from above from cooling
this sprinkler and
preventing its operation

76
Concealed Sprinkler
 Decorative white disk is
soldered to the sprinkler
body – solder melts first,
plate falls to floor,
exposing sprinkler
 Exposed sprinkler will now
operate like a standard
sprinkler - releases water as
temperature increases
 Can be used in Light
Hazard Occupancies

77
Partial Data Sheet for a Typical
Concealed Sprinkler

79
 Requirements for water supply capacity and
spacing of sprinklers depend upon the
building’s occupancy classification
 Occupancy Classes:
 Light
 Ordinary Group 1
 Ordinary Group 2
 Extra Group 1
 Extra Group 2

80
Light Hazard
 Quantity and/or combustibility of contents is
low; fires with relatively low rates of heat
release are expected.
 Examples:
 Churches
 Libraries
 Restaurant seating areas

81
Ordinary Hazard
 Group 1 – combustibility is low, quantity of
combustibles is moderate, stockpiles of
combustibles do not exceed 8 ft, fires with
moderate rates of heat release expected.
 Examples:
 Automobile parking and showrooms
 Bakeries
 Restaurant service areas

82
Ordinary Hazard (cont’d)
 Group 2 – quantity and combustibility of
contents moderate to high, stockpiles do not
exceed 12 ft, fires with moderate to high rates
of heat release expected.
 Examples:
 Chemical plants - ordinary
 Dry Cleaners
 Library large stack room areas

83
Extra Hazard
 Group 1 – combustibility is low, quantity of
combustibles is very high, dust, lint or other
materials are present, possibility of rapidly
developing fires with high rates of heat release, but
little or now combustible or flammable liquids.
 Examples:
 Aircraft hangers
 Plywood and particle board manufacturing
 Printing

84
Extra Hazard (cont’d)
 Group 2 – moderate to substantial amounts of
flammable or combustible liquids
 Examples:
 Flammable liquids spraying
 Plastics processing
 Varnish and paint dipping
 In all cases, refer to NFPA 13 and AHJ (Authority
Having Jurisdiction) for quidance in assessing
occupancy classification

85
 Maximum Area of Coverage (Standard Spray
Upright and Pendant Sprinklers)
 Light hazard: 225 s.f., maximum 15’ between sprinklers
 Ordinary hazard: 130 s.f., maximum 15’ between
sprinklers
 Extra hazard: 90 s.f., maximum 12’ between sprinklers
(see NFPA 13 for exceptions)
 Protection Area per sprinklers:
 S x L, where S = spacing between sprinklers or twice
distance to end wall, whichever is greater.
 L = spacing between branch lines or twice the distance to
end wall, whichever is greater.

86
 Maximum distance from walls: less than ½ spacing.
 Minimum distance to walls: 4”
 Where walls are angled or irregular, the maximum
distance to any point on floor – 0.75 spacing, with
maximum perpendicular distance to wall not
exceeded.
 Minimum distance between sprinklers: 6’ (see
exceptions NFPA 13)

87
Sprinkler Location
 Deflector position
 Standard spray pendant or upright heads:
minimum 1” to maximum 12” from ceiling.
 Standard spray sidewall sprinklers: minimum 4”
to maximum 6” from ceiling. (In special
situations, 6 to 12” – see NFPA 13)
 Critical point – the farther the sprinkler is from
the ceiling, the longer it will take for the heat to
collect at the ceiling plane and set off the
sprinkler.

89
Sprinkler Spacing Examples
 Light Hazard Occupancy
 225 s.f. per sprinkler
 Maximum 15’ between
branch lines and between
sprinklers on branch lines
 Maximum 15/2 = 7.5 from
wall to outermost sprinkler
and branch lines
 Here, S=L=15’

90
Sprinkler Spacing Example No. 2
 Occupancy Hazard:
Ordinary Group 1
 Maximum coverage
per sprinkler: 130 s.f.
 Maximum spacing: 15’

91
Example No. 2 – Proposed Solution
 Area of coverage is 10’x
13’ = 130 s.f.
 Maximum spacing is 13’,
which is less than the
maximum 15’ allowed
 Maximum distance to wall
is 6.5’, which is ½ the
largest spacing (13’)
 Yet this solution does not
comply with NFPA 13!

92
Example No. 2 (cont’d)
 Area of coverage of
sprinkler in NW corner
is: (6+5) x 13 = 141 s.f.
 The number of
sprinklers required is
actually (41’ x
39’)/130 s.f. per
sprinkler = 12.3; the
proposed solution has
just 12

93
 Here is one correct
solution.
 More sprinklers are
required in order to
comply with both
spacing and area of
coverage requirements.
 S=12’ (2 x 6); L=9’-8”
 A=12’ x 9’-8” =
116.04 s.f

94
 If a 2’x2’ suspended
tile ceiling is used, the
sprinklers will not be
centered within the
tiles.

95
Example No. 2 (conclusion)
 Since we have more
sprinklers than are needed,
we can shift the centerlines
slightly to achieve center of
tile placement of
sprinklers.
 In this example, the dashed
area represents greatest
coverage, = (5’-6” +5’-0”)
x (5’-0” + 6’-0”) = 126.5
s.f.

96
 Sprinkler Classifications
 Design and performance
 Area of coverage
 Speed of response
 Standard response
 Fast response
 Orientation
 Concealed
 Flush
 Pendent
 Recessed
 Sidewall
 Upright

97
Sprinkler Classifications (cont’d)
 Special service conditions
 Dry
 Corrosion resistant
 Intermediate level sprinkler/rack storage sprinkler

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