+---
+title: Smoke Control Systems
+category: Mechanical / Air Distribution
+toc_depth: 3
+description: >
+ When to use: Engineered mechanical smoke control systems triggered by code, including
+ stairwell pressurization, elevator hoistway pressurization, zoned (floor-by-floor)
+ smoke control, and atrium or large-volume mechanical exhaust, together with their
+ dedicated fans, smoke and combination dampers, listed control panels, and firefighter's
+ smoke control station.
+ Not intended for: General comfort HVAC air distribution, passive smoke barriers and
+ smoke partitions provided by architectural construction alone, kitchen grease exhaust,
+ or fire suppression systems. Use the air-handling, fire alarm, and damper standards for
+ those scopes.
+---
+
+# Scope {toc}
+
+## This standard covers engineered mechanical smoke control systems that use fans, dampers, and dedicated controls to manage the movement of smoke during a fire event. Smoke control is the active counterpart to passive compartmentation: it uses pressure differences and directed airflow to keep tenable conditions on exit paths and to limit smoke migration while occupants evacuate and firefighters respond. The work of this standard includes stairwell pressurization, elevator hoistway pressurization, zoned smoke control, and atrium or large-volume exhaust systems, with their fans, dampers, ductwork interfaces, listed control panels, and the firefighter's smoke control station. {note}
+
+## The Contractor shall provide a complete and operational smoke control system, including all fans, dampers, controls, wiring, and accessories required for a functioning system whether or not every item is specifically called out.
+
+## The smoke control method, served spaces, and quantities shall be as indicated. [[drawing: smoke control system diagram and equipment schedule]]
+
+## The smoke control design approach, design fire scenario, and assumed boundary leakage shall be established in the project basis of design and shall not be altered by the Contractor without the engineer of record's written approval.
+
+## This standard does not cover the following, which are specified elsewhere and are referenced here only at their interfaces with the smoke control system: {note}
+
+- Passive smoke barriers, smoke partitions, and architectural opening protectives, governed by the architectural and life-safety documents, except where their leakage values are inputs to the smoke control design
+- Fire suppression piping, specified in the fire suppression documents
+- Fire alarm initiating and notification devices, specified in [[syncs/fire-alarm-systems]]
+- General comfort air distribution, specified in [[syncs/hvac-fans]]
+
+## Related work is specified in [[syncs/hvac-fans]], [[syncs/louvers-and-dampers]], [[syncs/fire-alarm-systems]], [[syncs/building-automation-system]], and [[syncs/testing-adjusting-and-balancing]]. {note}
+
+# Definitions {toc}
+
+## The following terms apply to this standard: {note}
+
+- **Smoke control system** means an engineered system that uses mechanical fans to produce airflows and pressure differences across smoke barriers to limit and direct the movement of smoke.
+- **Dedicated smoke control system** means a system installed for the sole purpose of smoke control; its equipment serves no other function.
+- **Non-dedicated smoke control system** means a system that shares all or part of its equipment with the building's normal heating, ventilating, and air-conditioning function and is reconfigured to smoke control mode on command.
+- **Pressurization method** means a smoke control approach that maintains a design pressure difference across a barrier to hold smoke on the fire side; it is the basis for stairwell and hoistway pressurization.
+- **Exhaust method** means a smoke control approach that mechanically removes smoke from a large volume at a rate derived from plume calculations, with make-up air introduced at low level; it is the basis for atrium and large-volume systems.
+- **Zoned smoke control** means a floor-by-floor approach that exhausts the smoke zone while pressurizing adjacent zones to confine smoke to the zone of origin.
+- **Firefighter's smoke control station**, abbreviated FSCS, means the central manual control and status interface from which the fire service monitors and overrides the smoke control system.
+- **Opposed door force** means the force required to open a door against the pressure difference produced by the system; it is the constraint that caps achievable pressurization.
+
+# Referenced Standards {toc}
+
+## The publications listed below form a part of this standard to the extent referenced. The edition adopted by the authority having jurisdiction governs; where no edition is adopted, the most recent edition applies. {note}
+
+## NFPA 92 is the primary design and acceptance standard for engineered mechanical smoke control and governs pressure differences, exhaust rates, and testing. The edition in widest current adoption is the 2021 edition; a 2024 edition has been published and is entering adoption, and the edition referenced by the authority having jurisdiction shall be confirmed before design. {note}
+
+## The applicable design and listing standards include the following. {note}
+
+| Standard | Title |
+|----------|-------|
+| NFPA 92 | Standard for Smoke Control Systems |
+| NFPA 105 | Standard for Smoke Door Assemblies and Other Opening Protectives |
+| NFPA 4 | Standard for Integrated Fire Protection and Life Safety System Testing |
+| NFPA 110 | Standard for Emergency and Standby Power Systems |
+| IBC Section 909 | International Building Code, Smoke Control Systems |
+| IMC Section 513 | International Mechanical Code, Smoke Control Systems |
+| UL 864 | Control Units and Accessories for Fire Alarm Systems (UUKL smoke control category) |
+| UL 555 | Standard for Fire Dampers |
+| UL 555S | Standard for Smoke Dampers |
+| UL 1784 | Air Leakage Tests of Door Assemblies and Other Opening Protectives |
+| ANSI/AMCA 99 | Standards Handbook (fan classification and temperature codes) |
+| ANSI/AMCA 500-D | Laboratory Methods of Testing Dampers for Rating |
+| ASHRAE Handbook | HVAC Applications, Smoke Management chapter |
+
+### The design shall comply with the smoke control provisions of the adopted building code, including the firefighter's smoke control station, detection, pressurization, special inspection, and acceptance testing subsections of IBC Section 909.
+
+### Where this standard and a referenced document conflict, the more stringent requirement shall govern unless the authority having jurisdiction directs otherwise.
+
+# Submittals {toc}
+
+## Action Submittals {toc}
+
+### The Contractor shall submit the following action submittals for review before fabrication or installation:
+
+- Smoke control system shop drawings showing fans, dampers, control panels, the FSCS, and the smoke control diagram
+- Sequence of operations for each smoke control mode, including automatic activation, manual override, and the weekly self-test
+- Product data for fans, including AMCA 99 temperature classification and certified performance at the design operating temperature
+- Product data for smoke dampers and combination fire/smoke dampers, including UL listing, leakage class, and actuator temperature rating
+- Product data and UL 864 UUKL listing documentation for the smoke control panel and the FSCS
+- Wiring and interface drawings between the smoke control panel, the fire alarm control unit, and the building automation system
+- Design basis narrative including the smoke control method, design fire scenario, and assumed boundary leakage values
+
+```datasheet
+label: Action Submittals
+type: checkbox
+options:
+ - Smoke control shop drawings and system diagram
+ - Sequence of operations (all modes + self-test)
+ - Fan product data with AMCA 99 temperature class
+ - Smoke / combination damper product data and listings
+ - UL 864 UUKL panel and FSCS product data
+ - Control interface and wiring drawings
+ - Design basis narrative
+default:
+ - Smoke control shop drawings and system diagram
+ - Sequence of operations (all modes + self-test)
+ - Fan product data with AMCA 99 temperature class
+ - Smoke / combination damper product data and listings
+ - UL 864 UUKL panel and FSCS product data
+ - Control interface and wiring drawings
+```
+
+## Informational Submittals {toc}
+
+### The Contractor shall submit the following informational submittals:
+
+- Manufacturer certification that fans for exhaust service are rated and tested for the design operating temperature and duration
+- Manufacturer certification that smoke dampers are UL 555S listed at the specified leakage class and actuator temperature
+- UL 864 UUKL listing certificate for the assembled control panel and FSCS
+- Special inspection agency qualifications for smoke control special inspection
+- Integrated testing agent qualifications for NFPA 4 integrated testing
+
+```datasheet
+label: Informational Submittals
+type: checkbox
+options:
+ - Fan elevated-temperature rating certification
+ - Smoke damper UL 555S certification
+ - UL 864 UUKL listing certificate
+ - Special inspection agency qualifications
+ - Integrated testing agent qualifications
+default:
+ - Fan elevated-temperature rating certification
+ - Smoke damper UL 555S certification
+ - UL 864 UUKL listing certificate
+```
+
+## Closeout Submittals {toc}
+
+### The Contractor shall submit the following closeout submittals before final acceptance:
+
+- Acceptance test report per NFPA 92, including differential pressure, door force, and exhaust flow results
+- Integrated testing report per NFPA 4
+- Special inspection final report per the adopted building code
+- Record drawings showing as-built equipment, dampers, and control wiring
+- Operation and maintenance manuals including programmed sequences and self-test logs
+- Warranty documentation
+
+```datasheet
+label: Closeout Submittals
+type: checkbox
+options:
+ - NFPA 92 acceptance test report
+ - NFPA 4 integrated testing report
+ - Special inspection final report
+ - Record drawings
+ - Operation and maintenance manuals
+ - Warranty documentation
+default:
+ - NFPA 92 acceptance test report
+ - NFPA 4 integrated testing report
+ - Special inspection final report
+ - Record drawings
+ - Operation and maintenance manuals
+ - Warranty documentation
+```
+
+# Quality Assurance {toc}
+
+## The smoke control system is a life-safety system whose failure modes are not apparent during normal building operation; rigorous qualification, listing, and inspection are therefore the principal assurance that the system will perform when called upon. {note}
+
+### The smoke control panel and the firefighter's smoke control station shall be UL 864 listed under the UUKL smoke control category.
+
+### All smoke dampers shall be UL 555S listed.
+
+### All fire dampers shall be UL 555 listed, and combination fire/smoke dampers shall be listed under both UL 555 and UL 555S.
+
+### Fans used in smoke exhaust service shall carry an AMCA 99 temperature classification and shall be certified for operation at the design operating temperature and duration.
+
+### A confusion between fire dampers and smoke dampers is a recurring and consequential error: a fire damper closes on heat to maintain a rated barrier and is not a smoke damper, and a smoke damper controls smoke leakage and does not by itself maintain a fire rating; where both functions occur at one opening a combination damper carrying both listings is required. {note}
+
+### The installer shall be experienced in smoke control system installation and shall be acceptable to the smoke control panel manufacturer for control work.
+
+### Smoke control systems require special inspection by a qualified agency under the adopted building code, and this special inspection shall be included in the project special inspection program.
+
+### Integrated testing of the smoke control system with the fire alarm and suppression systems shall be performed by a qualified integrated testing agent in accordance with NFPA 4.
+
+```datasheet
+label: System Listing and Classification
+type: select
+options:
+ - Dedicated system, UL 864 UUKL standalone panel
+ - Non-dedicated system, UL 864 UUKL controls on shared equipment
+ - Integrated with UUKL-listed fire alarm control unit
+default: Dedicated system, UL 864 UUKL standalone panel
+```
+
+# Smoke Control Method and Design Approach {toc}
+
+## The selection of smoke control method follows from occupancy, building geometry, and the specific code trigger, and it determines every downstream equipment and control decision; it shall be fixed in the basis of design before equipment is selected. {note}
+
+### The smoke control method for each served space shall be as established in the basis of design and indicated on the smoke control diagram. [[drawing: smoke control method per zone]]
+
+### Stairwell pressurization shall maintain a design pressure difference across the stair enclosure door sufficient to resist smoke infiltration while remaining within the opposed door force limit.
+
+### The opposed door force shall not exceed 30 lbf to open any door, measured with the system operating and all doors closed, in accordance with NFPA 92.
+
+### The 30 lbf door force limit caps the pressure difference that a stairwell can sustain, because a single high-mounted injection point over-pressurizes the lower floors of a tall shaft; tall stairwells therefore require multi-injection or variable-volume designs to distribute pressure and stay within the force limit. {note}
+
+### The minimum design pressure difference across smoke barriers for the pressurization method shall be as established by NFPA 92 for the building's ceiling height and sprinkler condition, and shall be confirmed in the basis of design.
+
+### The exhaust method shall remove smoke from the large-volume space at a rate derived from plume calculations in accordance with NFPA 92, with make-up air introduced at low level at a velocity that does not disrupt the smoke plume.
+
+### The design fire heat release rate used for plume and exhaust calculations shall be documented and justified in the basis of design, because exhaust rate is highly sensitive to the assumed fire size and an unjustified default value yields an under- or over-designed system. {note}
+
+### Make-up air velocity at the make-up air openings shall not exceed the limit established by NFPA 92 to avoid deflecting or disrupting the smoke plume.
+
+### Zoned smoke control shall exhaust the smoke zone and pressurize adjacent zones to confine smoke to the zone of fire origin.
+
+```datasheet
+label: Smoke Control Method
+type: select
+options:
+ - Stairwell pressurization
+ - Elevator hoistway pressurization
+ - Zoned (floor-by-floor) smoke control
+ - Atrium / large-volume mechanical exhaust
+default: Stairwell pressurization
+```
+
+```datasheet
+label: Design Approach
+type: select
+options:
+ - Pressurization-differential method
+ - Exhaust-rate (plume calculation) method
+default: Pressurization-differential method
+```
+
+```datasheet
+label: Design Pressure Difference Across Barrier
+type: range
+unit: in. w.g.
+min: 0.05
+max: 0.25
+step: 0.01
+setpoints:
+ - 0.05
+ - 0.10
+default: 0.10
+```
+
+```datasheet
+label: Maximum Door-Opening Force (Opposed Door Force)
+type: range
+unit: lbf
+min: 0
+max: 30
+step: 1
+default: 30
+```
+
+```datasheet
+label: Assumed Simultaneously Open Doors (Stair Pressurization)
+type: range
+unit: doors
+min: 1
+max: 3
+step: 1
+default: 1
+```
+
+# Stairwell Pressurization {toc}
+
+## Stairwell pressurization keeps a positive pressure in the exit stair relative to the building so that smoke cannot enter the protected egress path; the engineering challenge is holding that pressure uniformly over the height of the shaft without exceeding the door force limit at any floor. {note}
+
+### Stairwell pressurization shall maintain the design pressure difference across the stair enclosure at every floor with the design number of doors open.
+
+### Single-injection stairwell pressurization may be used only where analysis confirms the design pressure difference and the door force limit are simultaneously satisfied at every floor.
+
+### Multi-injection stairwell pressurization with distributed injection points shall be used where a single injection point cannot satisfy both the design pressure difference and the door force limit, as is typical for tall shafts.
+
+### Multi-injection systems shall include variable-volume control, by variable-speed fan or modulating relief, to maintain the design pressure difference as doors open and close.
+
+### Where a smokeproof enclosure is required, a pressurized vestibule shall be provided as a second barrier between the building and the stair in accordance with the adopted building code.
+
+### Stairwell pressurization fans shall draw outdoor air from a location not subject to smoke recirculation from building exhaust or relief openings.
+
+### A barometric relief or modulating relief damper shall be provided where required to prevent over-pressurization of the stair when all doors are closed.
+
+```datasheet
+label: Stairwell Pressurization Configuration
+type: select
+options:
+ - Single-injection (top or bottom)
+ - Multi-injection, variable-volume
+ - Vestibule (smokeproof enclosure) pressurization
+default: Multi-injection, variable-volume
+```
+
+```datasheet
+label: Multi-Injection Spacing
+type: range
+unit: floors per injection
+min: 1
+max: 5
+step: 1
+default: 3
+```
+
+```datasheet
+label: Pressurization Fan Capacity Control
+type: select
+options:
+ - Variable-speed drive
+ - Modulating relief damper
+ - Bypass / barometric relief
+default: Variable-speed drive
+```
+
+# Elevator Hoistway Pressurization {toc}
+
+## Elevator hoistways connect every floor of a building through a continuous vertical shaft and can act as a chimney that distributes smoke building-wide; pressurizing the hoistway holds smoke out of the shaft and protects the elevators used by occupants and the fire service. {note}
+
+## Elevator hoistway pressurization shall be provided where required by the adopted building code, including high-rise and underground conditions; omitting hoistway pressurization where the code triggers apply is a common and consequential design oversight. {note}
+
+### Elevator hoistway pressurization shall maintain the design pressure difference across the hoistway entrance at the served floors.
+
+### The hoistway pressurization fan shall inject air at the top of the hoistway and shall pressurize the hoistway and associated machine room where required.
+
+### Hoistway pressurization shall be coordinated with elevator door operation and with the elevator recall sequence so that pressurization does not impede door closing or recall.
+
+### The hoistway pressurization system shall include capacity control to maintain the design pressure difference as hoistway doors open and close.
+
+```datasheet
+label: Hoistway Pressurization Provided
+type: radio
+options:
+ - "Yes"
+ - "No"
+default: "Yes"
+```
+
+```datasheet
+label: Hoistway Pressurization Fan Location
+type: select
+options:
+ - Top of hoistway, roof-mounted
+ - Top of hoistway, machine room
+default: Top of hoistway, roof-mounted
+```
+
+# Smoke Exhaust Fans {toc}
+
+## Fans serving a smoke exhaust stream may handle hot smoke for the duration of the event, so they are not ordinary HVAC fans: they must be rated, classified, and factory-tested to run at elevated temperature without failure of bearings, drive, or motor. {note}
+
+### Fans in smoke exhaust service shall carry an AMCA 99 temperature classification and shall be certified by the manufacturer for continuous operation at the design operating temperature and duration.
+
+### The AMCA 99 temperature class code shall be cited explicitly in the equipment schedule in addition to the UL listing, because the temperature class defines the maximum operating temperature and duration the fan is rated for. {note}
+
+### Specifying a standard comfort-HVAC fan for smoke exhaust service is a defect: such a fan lacks the temperature-rated bearings, drive, and motor placement required for hot smoke and will not carry an AMCA 99 elevated-temperature classification. {note}
+
+### Smoke exhaust fans shall be selected for the design exhaust flow rate and external static pressure of the smoke control system, not the comfort ventilation condition.
+
+### Belt-driven smoke exhaust fans shall locate the motor and drive outside the elevated-temperature airstream or shall use components rated for the airstream temperature.
+
+### Smoke exhaust fan motors and controls shall be connected to the emergency power supply system in accordance with NFPA 110.
+
+### Fans and fan accessories common to comfort and smoke service shall additionally comply with [[syncs/hvac-fans]]. {note}
+
+```datasheet
+label: Smoke Exhaust Fan Type
+type: select
+options:
+ - Centrifugal, backward-curved / airfoil, belt-drive
+ - Centrifugal, backward-curved / airfoil, direct-drive
+ - Vane-axial
+default: Centrifugal, backward-curved / airfoil, belt-drive
+```
+
+```datasheet
+label: Fan Elevated-Temperature Rating (AMCA 99 Temperature Class)
+type: select
+options:
+ - 300°F continuous
+ - 300°F for 4 hours
+ - 500°F for 1 hour
+default: 300°F for 4 hours
+```
+
+```datasheet
+label: Smoke Exhaust Fan Design Airflow
+type: range
+unit: cfm
+min: 2000
+max: 120000
+step: 500
+default: 30000
+drawing_ref: "exhaust fan schedule"
+```
+
+```datasheet
+label: Smoke Exhaust Fan External Static Pressure
+type: range
+unit: in. w.g.
+min: 0.5
+max: 6.0
+step: 0.25
+default: 2.0
+```
+
+```datasheet
+label: Fan Power Source
+type: select
+options:
+ - Emergency power supply system (generator)
+ - Emergency power supply system with UPS ride-through
+default: Emergency power supply system (generator)
+```
+
+# Smoke and Combination Dampers {toc}
+
+## Dampers in a smoke control system either hold smoke out of protected paths or direct exhaust along the intended route, and their leakage and temperature rating must match the assumptions in the smoke control model or the system will not achieve its design pressures. {note}
+
+### Smoke dampers shall be UL 555S listed at the specified blade leakage class and actuator temperature rating.
+
+### The smoke damper leakage class shall match the barrier leakage assumed in the smoke control design, because a leakier damper than assumed defeats the pressure differential the design relies on. {note}
+
+### Smoke damper leakage classes are defined by ANSI/AMCA 500-D, where Class I is the tightest and Class III the loosest; Class I or Class II is typical for smoke control service. {note}
+
+### The smoke damper actuator and assembly temperature rating shall be selected for the maximum smoke temperature expected at the damper location.
+
+### Smoke dampers on an exhaust path that may carry hot smoke shall be rated for elevated temperature, because exhaust smoke in a fully developed fire can exceed the standard 250°F rating and a standard-rated actuator may fail in service. {note}
+
+### Combination fire/smoke dampers shall be provided where a smoke control damper occurs at a rated fire barrier, and shall be listed under both UL 555 and UL 555S.
+
+### Damper actuators shall fail to the position required by the smoke control sequence on loss of power or control signal.
+
+### Smoke damper actuators shall be electric where required to support the supervised, addressable control and position feedback required by the smoke control panel.
+
+### Dampers, sleeves, and access provisions common to general HVAC service shall additionally comply with [[syncs/louvers-and-dampers]]. {note}
+
+```datasheet
+label: Smoke Damper Leakage Class (AMCA 500-D)
+type: select
+options:
+ - Class I
+ - Class II
+ - Class III
+default: Class I
+```
+
+```datasheet
+label: Smoke Damper Temperature Rating (UL 555S)
+type: select
+options:
+ - 250°F (121°C) standard
+ - 350°F (177°C) elevated
+default: 250°F (121°C) standard
+```
+
+```datasheet
+label: Damper Type
+type: select
+options:
+ - Smoke damper (UL 555S)
+ - Combination fire/smoke damper (UL 555 + UL 555S)
+default: Smoke damper (UL 555S)
+```
+
+```datasheet
+label: Damper Actuator Type
+type: select
+options:
+ - Electric, two-position
+ - Electric, modulating
+default: Electric, two-position
+```
+
+```datasheet
+label: Actuator Fail Position
+type: select
+options:
+ - Fail open
+ - Fail closed
+ - Fail in last position
+default: Fail closed
+```
+
+# Smoke Barriers and Opening Protectives {toc}
+
+## The smoke control design models the building envelope and its internal barriers as a network of leakage paths, and the achieved pressure differences depend directly on the as-built leakage of doors, walls, and penetrations matching the modeled values. {note}
+
+### Smoke door assemblies used as smoke barriers shall comply with the air leakage limits of NFPA 105, not exceeding 3.0 cfm per square foot at 0.10 in. w.g. when tested in accordance with UL 1784.
+
+### Artificial bottom seals shall not be installed on doors in pressurized installations, because such seals are prohibited by NFPA 105 for these assemblies and can mask leakage assumed in the design. {note}
+
+### As-built smoke barrier leakage shall be consistent with the values assumed in the smoke control design; field hardware, door undercuts, and unsealed penetrations frequently exceed design assumptions and cause acceptance pressure differences to fail. {note}
+
+### Penetrations of smoke barriers serving the smoke control system shall be sealed to maintain the barrier leakage assumed in the design.
+
+### Smoke door leakage shall be verified during acceptance testing against the design boundary leakage values.
+
+```datasheet
+label: Smoke Door Maximum Air Leakage (NFPA 105 / UL 1784)
+type: range
+unit: cfm/ft² at 0.10 in. w.g.
+min: 1.0
+max: 3.0
+step: 0.5
+default: 3.0
+```
+
+# Ductwork and Leakage {toc}
+
+## Smoke control ducts operate at the elevated pressures the fans develop and must hold those pressures with low leakage, because duct leakage is a direct loss of the airflow the design depends on and is checked by a dedicated pressure test. {note}
+
+### Smoke control duct construction shall be rated for the maximum operating pressure of the smoke control system in accordance with the adopted mechanical code.
+
+### Smoke control duct leakage shall not exceed 5 percent of the design flow when tested at 1.5 times the maximum design operating pressure.
+
+### General HVAC duct sealing classes alone are insufficient for smoke control, and the duct leakage requirement and pressure-test condition shall be cited explicitly so that the duct is tested to the smoke control criterion rather than only a general sealing class. {note}
+
+### Smoke control ducts shall be tested for leakage before concealment and before acceptance testing of the system.
+
+```datasheet
+label: Maximum Duct Leakage
+type: range
+unit: % of design flow
+min: 1
+max: 5
+step: 1
+default: 5
+```
+
+```datasheet
+label: Duct Leakage Test Pressure
+type: range
+unit: × maximum design pressure
+min: 1.0
+max: 1.5
+step: 0.1
+default: 1.5
+```
+
+# Control Panel and Firefighter's Smoke Control Station {toc}
+
+## The control panel is the brain of the system and the FSCS is the fire service's hands on it; both are life-safety listed equipment, and the boundary between the smoke control controls and the fire alarm system is a frequent source of interface gaps that must be coordinated and assigned. {note}
+
+### The smoke control panel shall be UL 864 listed under the UUKL smoke control category.
+
+### Where the smoke control function is integrated with the fire alarm control unit, the fire alarm control unit and its smoke control modules shall carry the UL 864 UUKL listing.
+
+### A non-dedicated system that reconfigures shared HVAC equipment for smoke control shall provide UL 864 UUKL-listed controls for all shared components, because standard building automation controls on shared equipment used for smoke control do not satisfy the listing requirement and will be rejected at inspection. {note}
+
+### A firefighter's smoke control station shall be provided at the location required by the adopted building code for fire service access. [[drawing: FSCS location]]
+
+### The FSCS shall display the status of each smoke control fan and damper and shall provide manual override of each smoke control function.
+
+### The FSCS override hierarchy shall provide, at minimum, automatic mode, manual on, and manual off control of each function, with manual override taking precedence over automatic control.
+
+### A graphic-annunciator FSCS shall present a backlit graphic representation of the building with status indication and override controls keyed to the smoke control zones.
+
+### A switch-based FSCS shall present a labeled matrix of override switches with status indication for each function.
+
+### The division of the FSCS scope between the fire alarm installer and the mechanical controls installer shall be coordinated and assigned so that programming, wiring, and status interfaces are complete with no gaps. {note}
+
+### Fire alarm initiation, detection, and interface devices that activate the smoke control system are specified in [[syncs/fire-alarm-systems]], and the smoke control interface with general building controls is coordinated with [[syncs/building-automation-system]]. {note}
+
+```datasheet
+label: Control Panel Architecture
+type: select
+options:
+ - Dedicated standalone UL 864 UUKL panel
+ - Integrated with UL 864 UUKL fire alarm control unit
+default: Dedicated standalone UL 864 UUKL panel
+```
+
+```datasheet
+label: FSCS Type
+type: select
+options:
+ - Graphic annunciator with override push-buttons
+ - Switch-based matrix with status LEDs
+default: Graphic annunciator with override push-buttons
+```
+
+```datasheet
+label: FSCS Override Modes
+type: checkbox
+options:
+ - Automatic
+ - Manual on
+ - Manual off
+default:
+ - Automatic
+ - Manual on
+ - Manual off
+```
+
+# Sequence of Operation {toc}
+
+## The sequence of operation translates a detected fire into the correct fans running, dampers positioned, and barriers pressurized; it must be written explicitly for every mode because gaps in the sequence surface as requests for information during commissioning rather than as buildable instructions. {note}
+
+### A complete sequence of operation shall be provided for each smoke control mode, including automatic activation, manual override at the FSCS, and the weekly self-test.
+
+### Automatic activation of the smoke control system shall be initiated by the fire alarm system upon the detection signals defined in the basis of design.
+
+### Upon activation, smoke control fans shall start and smoke control dampers shall drive to the positions required for the active mode.
+
+### Dedicated smoke control systems shall perform an automatic self-test of all smoke control functions at intervals not exceeding seven days in accordance with UL 864.
+
+### The weekly automatic self-test sequence and its programming scope shall be included in the smoke control specification and controls programming, because omitting the self-test sequence is a frequent gap that generates requests for information at commissioning. {note}
+
+### The result of each automatic self-test shall be logged and any failure shall be annunciated at the FSCS and the fire alarm system.
+
+### Loss of power, loss of communication, and component failure shall be annunciated as a smoke control system trouble condition.
+
+```datasheet
+label: Automatic Self-Test Interval
+type: range
+unit: days
+min: 1
+max: 7
+step: 1
+default: 7
+```
+
+```datasheet
+label: Self-Test Result Annunciation
+type: checkbox
+options:
+ - Log at smoke control panel
+ - Annunciate at FSCS
+ - Annunciate at fire alarm system
+default:
+ - Log at smoke control panel
+ - Annunciate at FSCS
+ - Annunciate at fire alarm system
+```
+
+# Power and Standby Power {toc}
+
+## A smoke control system that loses power during a fire is no system at all, so its fans and controls are placed on the building's emergency power so they continue to run when normal power fails. {note}
+
+### Smoke control fans, dampers, and controls shall be supplied from the emergency power supply system in accordance with NFPA 110.
+
+### The emergency power supply system Type and Class shall be verified to comply with NFPA 110 for the smoke control load, because connecting smoke control to a standard normal/standby transfer without confirming the required Type and Class is a code deficiency. {note}
+
+### The transfer of smoke control loads to standby power shall occur within the transfer time required for the smoke control function.
+
+```datasheet
+label: Standby Power Source
+type: select
+options:
+ - Emergency power supply system per NFPA 110
+ - Emergency power supply system with UPS for controls
+default: Emergency power supply system per NFPA 110
+```
+
+# Testing {toc}
+
+## Acceptance testing is the moment the design assumptions meet reality; it measures the actual pressure differences, door forces, and exhaust flows and is the only proof the engineered system performs as intended. {note}
+
+### The smoke control system shall be acceptance tested in accordance with NFPA 92 before the certificate of occupancy.
+
+### Acceptance testing shall verify the design pressure difference across each smoke barrier with the design number of doors open and closed.
+
+### Acceptance testing shall verify that the opposed door force does not exceed 30 lbf at any door with the system operating and all doors closed.
+
+### Acceptance testing shall verify the design exhaust flow rate and make-up air condition for exhaust-method systems.
+
+### Integrated testing of the smoke control system with the fire alarm and fire suppression systems shall be performed in accordance with NFPA 4 before the certificate of occupancy.
+
+### The integrated testing scope per NFPA 4 shall be included in the project schedule and commissioning plan, because the integrated test is required before occupancy and is frequently overlooked until late in construction. {note}
+
+### Periodic re-testing of the integrated system shall be performed at intervals not exceeding those required by NFPA 4.
+
+### Special inspection of the smoke control system shall be performed by a qualified agency in accordance with the adopted building code.
+
+### Air balancing of smoke control airflows shall be coordinated with [[syncs/testing-adjusting-and-balancing]]. {note}
+
+```datasheet
+label: Acceptance Test Scope
+type: checkbox
+options:
+ - Differential pressure across barriers
+ - Opposed door force measurement
+ - Exhaust flow and make-up air verification
+ - Damper operation and position verification
+ - Sequence of operation verification
+ - Weekly self-test verification
+default:
+ - Differential pressure across barriers
+ - Opposed door force measurement
+ - Damper operation and position verification
+ - Sequence of operation verification
+ - Weekly self-test verification
+```
+
+```datasheet
+label: Integrated Testing (NFPA 4) Re-Test Interval
+type: range
+unit: years
+min: 1
+max: 10
+step: 1
+default: 10
+```
+
+# Installation {toc}
+
+## Installation shall be in accordance with the manufacturer's instructions, the approved shop drawings, and the adopted mechanical and building codes.
+
+### Smoke dampers shall be installed in the listed configuration, with the sleeve, clearances, and access provisions required by the UL 555S listing.
+
+### Combination fire/smoke dampers shall be installed in the rated barrier in accordance with the listing for the barrier type.
+
+### Smoke control dampers shall be installed with access for inspection, testing, and actuator maintenance.
+
+### Outdoor air intakes for pressurization fans shall be located to avoid drawing in smoke from building exhaust, relief, or vent openings. [[drawing: outdoor air intake location]]
+
+### Control wiring for smoke control functions shall be installed as supervised circuits in accordance with the UL 864 listing and the adopted code.
+
+### Field wiring between the smoke control panel, the fire alarm control unit, and the building automation system shall be installed and labeled per the approved interface drawings.
+
+# Delivery, Storage, and Handling {toc}
+
+## Equipment shall be delivered in the manufacturer's packaging with listing labels and rating tags intact and legible.
+
+### Dampers and actuators shall be stored protected from weather, dust, and physical damage until installation.
+
+### Control panels and the FSCS shall be protected from moisture and construction dust before and after installation.
+
+### Damaged listing labels or rating tags shall be cause for rejection, because the listing and temperature rating cannot be verified without them. {note}
+
+# Warranty {toc}
+
+## The Contractor shall warrant the smoke control system, including fans, dampers, and controls, against defects in materials and workmanship for the project warranty period.
+
+### The warranty shall include correction of any deficiency that causes the system to fail to meet the acceptance test criteria of NFPA 92.
+
+```datasheet
+label: Warranty Period
+type: select
+options:
+ - 1 year
+ - 2 years
+ - 5 years
+default: 1 year
+```
+
+# Spare Parts {toc}
+
+## The Contractor shall furnish spare smoke damper actuators of each type and rating used in the project.
+
+### The Contractor shall furnish spare fuses, indicating lamps, and control modules for the smoke control panel as recommended by the manufacturer.
+
+```datasheet
+label: Spare Smoke Damper Actuators
+type: range
+unit: % of installed
+min: 0
+max: 10
+step: 1
+default: 2
+```
+
+```datasheet
+label: Spare Parts Package
+type: checkbox
+options:
+ - Spare damper actuators (each type/rating)
+ - Spare panel fuses
+ - Spare indicating lamps / LEDs
+ - Spare control modules
+default:
+ - Spare damper actuators (each type/rating)
+ - Spare panel fuses
+ - Spare indicating lamps / LEDs
+```