2. 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. 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. 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. 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.
7. 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. 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. 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. 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. 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
15. 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. 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.
19. 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. 20
Smoke Detectors
Types
Spot
Beam
Design:
Ionization
Photoelectric
Spot Detector Accessories
Integral alarm
Typical use – motels and similar sleeping spaces
21. 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.
23. 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
27. 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. 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. 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
32. 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. 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. 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. 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.
39. 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. 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. 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. 42
Diagram of a Typical Combined
Sprinkler and Standpipe System
44. 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. 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. 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. 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. 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. 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. 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.
52. 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. 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. 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. 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. 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. 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. 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.
60. 60
Sprinkler Systems (cont’d)
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. 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.
64. 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. 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. 66
Diagram of a Dry Pipe Sprinkler
System
Upright heads must be
used, in order to allow
the piping to drain
completely.
67. 67
Sprinkler systems (cont’d)
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. 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
70. 70
Sprinkler Systems (cont’d)
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. 71
Sprinkler systems (cont’d)
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. 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
75. 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. 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
79. 79
Sprinkler systems (cont’d)
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. 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. 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. 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. 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. 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. 85
Sprinkler systems (cont’d)
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. 86
Sprinkler systems (cont’d)
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. 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. 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. 90
Sprinkler Spacing Example No. 2
Occupancy Hazard:
Ordinary Group 1
Maximum coverage
per sprinkler: 130 s.f.
Maximum spacing: 15’
91. 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. 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. 93
Example No. 2 (cont’d)
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. 94
Example No. 2 (cont’d)
If a 2’x2’ suspended
tile ceiling is used, the
sprinklers will not be
centered within the
tiles.
95. 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. 96
Sprinkler Systems (cont’d)
Sprinkler Classifications
Design and performance
Area of coverage
Speed of response
Standard response
Fast response
Orientation
Concealed
Flush
Pendent
Recessed
Sidewall
Upright