The document summarizes lessons learned from designing and commissioning smoke control systems. Key points include: coordinating the design between architectural, mechanical, and fire protection teams; properly calculating smoke exhaust needs based on the design fire; ensuring adequate makeup air is provided below the smoke level; and using appropriate smoke detection and leakage factors in the design. Smoke control fundamentals like pressurization, exhaust, and stair pressurization methods are also reviewed.

1. 3/11/2011
SMOKE CONTROL LESSONS
LEARNED: DESIGN AND
COMMISSIONING
Joshua D. Greene, P.E.
Rolf Jensen & Associates, Inc.
PRESENTATION SUMMARY
• Smoke Control Fundamentals
• Lessons Learned – Design
• Lessons Learned – Commissioning
SMOKE CONTROL FUNDAMENTALS
• Definitions
– Smoke Control System:
• An engineered system that uses mechanical fans to
produce pressure differences across smoke barriers to
inhibit smoke movement
– Smoke Exhaust System
• A mechanical or gravity system intended to move smoke
from the smoke zone to the exterior of the building,
including smoke removal, purging, and venting systems,
as well as the function of exhaust fans utilized to reduce
the pressure in a smoke zone
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2. 3/11/2011
SMOKE CONTROL FUNDAMENTALS
• Early Prescriptive
Requirements (up to
early 1990’s)
– Air Changes
– Operable Windows
• Current Prescriptive
Requirements
– Passive or active smoke
control
– Based on design fire and
specific guidelines for feature
being protected
SMOKE CONTROL FUNDAMENTALS
• Performance
Requirements
– Establish Performance
Goals
– Outline Design Method
– Document results of
performance analysis
– Fire Models
• Fire Dynamics
Simulator
• Contam
SMOKE CONTROL FUNDAMENTALS
• Where Required
– Covered Mall Buildings
– Atria
– Underground Buildings
– Stages* (smoke control or roof vents)
– Group I-3 windowless buildings
– Smoke-Protected Assembly Seating
– High-Rise (smokeproof enclosures)
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3. 3/11/2011
SMOKE CONTROL FUNDAMENTALS
• Types of Smoke
Control
– Passive Barriers
– A ti M th d
Active Methods
• Pressurization Method
• Exhaust Method
• Airflow Method
SMOKE CONTROL FUNDAMENTALS
• Passive Barriers
– Uses Smoke Barriers to
contain smoke (smoke
compartments)
– Smoke Dampers in Duct
Penetrations & Air Registers
– No Fan-Assisted Smoke
Control
SMOKE CONTROL FUNDAMENTALS
• Pressurization Method
– Primary method of smoke control per IBC
– Smoke Control Concept: Containment
• Stair Pressurization: Tenability
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4. 3/11/2011
SMOKE CONTROL FUNDAMENTALS
• Pressurization Method
– Smoke Control System creates a pressure
difference between smoke compartment with
fire and adjacent smoke compartments
Smoke
Non-Fire Side
Higher Pressure
Fire Side
Lower Pressure
Figure taken from “Principles of Smoke Management” by Klote and Milke
SMOKE CONTROL FUNDAMENTALS
• Airflow Method
– Method must be approved by the AHJ
– Rarely used, though it is a code permitted
method
th d
– Smoke Control Concept: Containment
SMOKE CONTROL FUNDAMENTALS
• Airflow Method
– Uses active fans / HVAC equipment to
create opposing airflow through openings
in the smoke compartment to limit smoke
movement from the fire compartment
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5. 3/11/2011
SMOKE CONTROL FUNDAMENTALS
• Exhaust Method
– Method most associated with smoke control
– Method must be approved by AHJ
– Mostly used in large spaces with high
ceilings
– Smoke Control Concept: Tenability
SMOKE CONTROL FUNDAMENTALS
• Exhaust Method
– Intent is to keep adjacent smoke
compartments free of smoke as well as to
p
remove smoke from the compartment of
origin to maintain a tenable environment for
occupants
– Not intended to remove all smoke from fire
compartment
SMOKE CONTROL FUNDAMENTALS
• Exhaust Method
– Typically uses active HVAC equipment to
exhaust smoke near the top of the space
p p
– Natural ventilation may sometimes be used,
but there are limits
• LEED
• Stratification issues
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6. 3/11/2011
SMOKE CONTROL FUNDAMENTALS
• Exhaust Method
– Goal is to keep smoke above highest level
open to the space used for occupant
p p p
egress
• 2000 and 2003 IBC: smoke level at 10 ft
• 2006 and 2009 IBC: smoke level at 6 ft
SMOKE CONTROL FUNDAMENTALS
mout
min
min
SMOKE CONTROL FUNDAMENTALS
• Stair Pressurization
– Smokeproof Enclosures
• Required where stairs serve floors more than
– 75 feet above the lowest level of fire department
vehicle access
– 30 feet below the level of exit discharge
– Three smokeproof enclosure options
• Stair pressurization most used
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7. 3/11/2011
SMOKE CONTROL FUNDAMENTALS
• Stair Pressurization
– Similar concept as pressurization method
• Pressure difference between stairs and
adjacent areas to reduce smoke migration into
stair
– Uses one or more pressurization fans
dedicated to the stair enclosure
SMOKE CONTROL FUNDAMENTALS
• Stair Pressurization
– Pressure Difference Requirements (IBC)
• Minimum = 0.10 inch H20
• Maximum = 0.35 inch H20
• Measured with all doors closed*
– Vestibule between stair and adjacent
spaces (corridor) not required, but
permitted.
LESSONS LEARNED - DESIGN
• Know Your Codes
– Code and edition make a difference
• 2006 IBC different than 2009 IBC
– Height of smoke level
– Duration of smoke control
– Review local amendments
• May impact your design
• West coast, in particular, modifies IBC
smoke control requirements
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8. 3/11/2011
LESSONS LEARNED - DESIGN
• Design Team Coordination
– Architect
• Location and design of barriers
– Mechanical Engineer
• System equipment (fans, dampers, etc.)
• Controls
• Configuration
– Fire Protection System Designer
• Proper zoning of systems
LESSONS LEARNED - DESIGN
• Smoke Exhaust Calculations
– Designers MUST calculate for all
applicable plumes
– Only axisymmetric plume is calculated
– Typically, the balcony spill plume
calculations result in larger exhaust rate
than axisymmetric plume
LESSONS LEARNED - DESIGN
• Smoke Exhaust Calculations
– Axisymmetric Plume – Balcony Spill Plume
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9. 3/11/2011
LESSONS LEARNED - DESIGN
• Design Fire
– Based on rational analysis
• Fuel characteristics and
configuration
fi ti
• Steady or unsteady fire
• Use best available data
– NFPA 92B Annex
– Actual fire test results
• Effectiveness of sprinkler
protection
LESSONS LEARNED - DESIGN
• Makeup Air
– Usually not incorporated into design early
enough
• Coordination between architect and mechanical
engineer
• Difficult to add after Design Development
– Necessary to regulate the negative
pressure (door opening force) caused by
smoke exhaust
LESSONS LEARNED - DESIGN
• Makeup Air
– Can be provided naturally, mechanically, or
a combination of both
• Often not enough is provided and high
Often,
velocities are the result
• Impacts door opening forces
– Must be provided entirely below the
smoke interface level
– Positive position confirmation devices
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10. 3/11/2011
LESSONS LEARNED - DESIGN
• Smoke Detection
– Activate smoke control
– Spot vs. Beam smoke detectors
• Spot – Will smoke plume hit the detectors?
• Beam – Need to account for smoke
stratification
LESSONS LEARNED - DESIGN
• Smoke Detection
– Spot Detectors and the Smoke Plume
Spot detectors on
balconies are not in
smoke plume
LESSONS LEARNED - DESIGN
• Smoke Detection
– Beam Detectors and Stratification
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11. 3/11/2011
LESSONS LEARNED - DESIGN
• Leakage Factors
– Are the IBC leakage factors appropriate for
the design?
• LEED/S t i bl D i – ti ht construction
LEED/Sustainable Design tighter t ti
– Incorrect leakage factors in design can
cause issues during commissioning
• Door opening forces
• Stair pressurization
– Example: CMU vs. Painted CMU
LESSONS LEARNED - DESIGN
• Properly Listed Equipment
– Control unit complying with UL 864 and
listed as smoke control equipment
q p
– UL Category UUKL listing
• Fire alarm equipment
• BAS equipment, if used as control equipment
LESSONS LEARNED - DESIGN
• Fire Fighter’s Smoke Control Panel
– Install in approved location
– Manual controls for mechanical smoke
control
– Control capabilities
• Provide control over equipment that can also
be controlled by other sources in the building
– ON-AUTO-OFF (Fans)
– OPEN-AUTO-CLOSE (Dampers)
– ON-OFF or OPEN-CLOSE (Equipment only
controlled at smoke control panel)
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12. 3/11/2011
LESSONS LEARNED - DESIGN
• Fire Fighter’s Smoke Control Panel
– Status indicators
• White – operating equipment normal status
• Red – operating equipment off or closed
• Green – operating equipment on or open
• Yellow/Amber – operating equipment fault
LESSONS LEARNED - DESIGN
• Fire Fighter’s Smoke Control Panel
– Designers often try to use fire alarm control
panel in lieu of smoke control panel
• Typically does not meet indicator requirements
– Make sure you confirm requirements with
the AHJ
• Indicators only
• Graphic panel
LESSONS LEARNED - DESIGN
• Fire Fighter’s Smoke Control Panel
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13. 3/11/2011
LESSONS LEARNED - DESIGN
• Stair Pressurization Equipment
– Must be independent of other equipment
– All equipment considered part of stair
enclosure
• Must protect the same way
LESSONS LEARNED - DESIGN
• Stair Pressurization Equipment
– 3 options
• Located exterior to building and directly
connected to stair enclosure or via ductwork
separated from building by 2-hour fire barriers
• Located within the stair enclosure with intake or
exhaust through ductwork separated from
building by 2-hour fire barriers
• Located within the building and completely
separated from the remainder of the building
by 2-hour fire barriers
LESSONS LEARNED - DESIGN
• Stair Pressurization Equipment
– Stair pressurization equipment wholly
within the stair enclosure is not required to
q
be separated from the stair enclosure
– Fire dampers are not required between
pressurization inlets and the stair
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14. 3/11/2011
LESSONS LEARNED - DESIGN
• Stair Pressurization Equipment
LESSONS LEARNED - DESIGN
• Stair Pressurization – Injection Points
– Single Injection – Multiple Injection
• Pressurization air – Pressurization air supplied to
supplied to stair stair enclosure at multiple
enclosure at one point vertically spaced inlets
• Limitation on number of – Need to accommodate shaft
in or adjacent to stair
stories that can be enclosure
served
– Separation of inlets not
– Recommended only codified
up 8 stories
• Typically every 3 to 8
– Up to 12 stories stories, depending on
possible designer
LESSONS LEARNED - DESIGN
• Stack Effect
– Air movement in
building due to
building and exterior
temperature variations
– Building air warmer
than outside air
(winter), upward
movement
– Building air cooler
than outside air
(summer), downward
movement
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15. 3/11/2011
LESSONS LEARNED - DESIGN
• Stack Effect
– Difficult to design for regions with large
temperature variations (like Chicago)
– Door opening forces/door closure
– Can greatly impact stair pressurization
– Barometric relief dampers (multiple?)
LESSONS LEARNED - COMMISSIONING
• Duct Leakage Testing
– IBC Requirements
• Tested at 150% of Maximum Design Pressure
• Limited to 5% of Design Flow
• Generally test ducts that traverse multiple
smoke zones
– Testing rarely anticipated or performed
LESSONS LEARNED - COMMISSIONING
• Testing Protocol
– Talk to the AHJ
• Avoid confusion or test
surprises
• Agree in advance on a test
plan
– Assist or lead efforts to
set testing protocol
• Don’t be passive
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16. 3/11/2011
LESSONS LEARNED - COMMISSIONING
• Cold or Hot “Smoke
Tests
– Limited value in
evaluating certain
system performance
– Validity as method of
testing a smoke-control
system is questionable
– NFPA 92A and 92B,
Annexes
REFERENCE MATERIALS
• Principles of Smoke Management, by John
Klote and Jim Milke (ASHRAE Publication)
• NFPA 92A, Standard for Smoke Control
Systems Utilizing Barriers and Pressure
Differences
• NFPA 92B, Standard for Smoke Management
Systems in Malls, Atria, and Large Spaces
• A Guide to Smoke Control in the 2006 IBC,
by Doug Evans and John Klote
Questions?
Joshua Greene, P.E.
Rolf Jensen & Associates, Inc.
312-879-7200
jgreene@rjagroup.com
j @j
rjainc.com
1-888-831-4RJA
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